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EXAMS for psych 241 with Diane Lee

by: Madison Ultimate Notetaker

EXAMS for psych 241 with Diane Lee psychobiology 241

Madison Ultimate Notetaker
Long Beach State

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These are the study guides completed by me for all of her exams. I hope this helps :)
Diane Lee
Cognitive Psychology, Psychology, Psychobiology, Psychobiology of Learning and Memory, Psychobio, exams, Study Guide, Studyguide
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This 114 page Bundle was uploaded by Madison Ultimate Notetaker on Wednesday September 28, 2016. The Bundle belongs to psychobiology 241 at California State University Long Beach taught by Diane Lee in Spring 2016. Since its upload, it has received 8 views. For similar materials see Psychobiology in Psychology (PSYC) at California State University Long Beach.

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Date Created: 09/28/16
E x a m 3 S t u d y G u i d e | 1 Exam 3 Psychobiology Chapter 4 Drugs Fit Like Keys into Molecular Locks  The effects of a drug depend on its dose  Drug doses are administered in many different ways  Repeated treatments can reduce the effectiveness of drugs Drugs Affect Each Stage of Neural Conduction and Synaptic Transmission  Some drugs alter presynaptic processes  Some drugs alter postsynaptic processes Drugs That Affect the Brain Can Be Divided into Functional Classes  Psychoactive drugs relieve severe symptoms  Psychoactive drugs alter consciousness Drug Abuse Is Pervasive  Several perspectives help us understand drug abuse  BOX 4.1: The Terminology of Substance-Related Disorders  Drug use, abuse, and dependence can be prevented or treated in multiple ways Questions 24) A state of decreased sensitivity to a drug as a result of previous exposure is called drug tolerance. When this effect generalizes to other drugs, it is referred to as cross-tolerance. A phenomenon called metabolic tolerance E x a m 3 S t u d y G u i d e | 2 refers to an increased ability of the body’s metabolic organs (e.g., the liver) to eliminate a drug. 25) Blockade of axonal transport is one way in which a drug can work on the presynaptic level to modulate transmitter production. Alteration of the number of postsynaptic receptors is one way in which a drug can work on the postsynaptic level to modulate transmitter receptors. 27)  LSD: activation of postsynaptic receptors  Reserpine: inhibition of transmitter storage in vesicles  Black widow venom: stimulation of transmitter release  Curare: blockade of postsynaptic receptors  Tetrodotoxin: axonal sodium channel blockade  Cocaine: inhibition of reuptake  Colchicine: inhibition of axonal transport  Lithium: inhibition of cAMP (or other second messenger). 29) Alcohol is produced by the fermentation of grains or fruit, and it has a biphasic effect in the nervous system, involving an initial stimulant phase followed by a prolonged depressant phase. Although it affects other transmitter systems too, alcohol particularly alters GABA transmission, activating the GABA rAceptor’s chloride channel. 30) Chronic use of alcohol is neurotoxic. True. MRI studies have shown that even bingeing (periodic consumption of alcohol) can reduce the rate of neurogenesis. 32)  Lysergic acid diethylamide (LSD): serotonin  Phencyclidine (PCP): NMDA-glutamate  Mescaline: norepinephrine and serotonin E x a m 3 S t u d y G u i d e | 3  Muscarine: acetylcholine  Psilocybin: serotonin  Ketamine: NMDA-glutamate  MDMA (“Ecstasy”): serotonin 33) Drugs that reduce anxiety are collectively known as anxiolytics; examples include neuroleptics False, haloperidol False, alcohol True, barbiturates True, amphetamines False, opiates True, and benzodiazepines True. 34) The major active substance in opium is morphine, which has very powerful analgesic properties and can be modified to produce the highly addictive compound heroin. 35) The main active ingredient in marijuana is delta-9- tetrahydrocannibinol; this and related substances are collectively known as cannabinoids. Cannabinoid receptors have been identified in the cerebellum True, spinal cord False, cerebral cortex True, substantia nigra True, and brainstem False. 37) Nicotine activates a class of acetylcholine receptors found especially at neuromuscular junctions but also in the CNS. By stimulating the sympathetic nervous system, nicotine increases heart rate and activates reward circuitry such as the VTA. Aside from its well-known harmful effects on the lungs and circulatory system, nicotine has been shown to improve cognitive performance. 38) Stimulants may act by increasing excitatory postsynaptic potentials or by decreasing normal inhibitory influences. E x a m 3 S t u d y G u i d e | 4 39) Cocaine acts by blocking monoamine transporters, especially those for dopamine, and thus it inhibits the reuptake of transmitters from synapses, prolonging their effect. Cocaine produces changes in cerebral blood flow and decreases in glucose utilization that are evident for months after a person stops using it. 40) The molecular structure of amphetamine resembles that of the catecholamine family of transmitters. Amphetamine potentiates the actions of these transmitters in three ways: facilitation of release, inhibition of reuptake, and competition for breakdown enzymes. 41) The drug Ecstasy, or MDMA, is a hallucinogenic form of amphetamine. Work with nonhuman animals suggests that chronic use of extremely high doses of Ecstasy has persistent effects on serotonin-containing neurons in the brain; changes that have been noted in these cells include damage to fine axons, although cell bodies appear to be spared. According to the study conducted by Fischer and colleagues in 1995, as long as 18 months after administration of 40 mg/kg of Ecstasy to monkeys, marked anatomical changes in the brain could be noted, especially in the neocortex. Such results remain controversial, given that this dose is rather high (a typical recreational dose for humans is less than 2 mg/kg). 43) The physical dependence model of drug use explains drug abuse as a desire to avoid symptoms of withdrawal. In the case of morphine abuse, these symptoms include tremors True, stupor False, irritability True, E x a m 3 S t u d y G u i d e | 5 convulsions False, confusion False, elevated heart rate and blood pressure True, and sedation False. 44)  Naltrexone: antagonist to the addicted drug  Antabuse: medication that blocks drug metabolism  Methadone: agonist of addicted drug  Drugs that reduce the desire to drink (certain antidepressants have this action): anticraving medication  Drugs, such as benzodiazepines, that control withdrawal symptoms: drug for detoxification Chapter 5 Sensory Information Processing Is Selective and Analytical  Sensory events are encoded as streams of action potentials  Sensory neurons respond to stimuli falling in their receptive fields  Receptors may show adaptation to unchanging stimuli  Sometimes we need receptors to be quiet Successive Levels of the CNS Process Sensory Information  Sensory cortex is highly organized  Sensory brain regions influence one another and change over time PART II Pain: The Body’s Emergency Signaling System Human Pain Varies in Several Dimensions A Discrete Pain Pathway Projects from Body to Brain  Peripheral receptors get the initial message  Special neural pathways carry pain information to the brain Pain Control Can Be Difficult E x a m 3 S t u d y G u i d e | 6  Analgesic drugs are highly effective  Electrical stimulation can sometimes relieve pain  Placebos effectively control pain in some people, but not all  Activation of endogenous opioids relieves pain PART III Pain: Movement and the Motor System Behavior Requires Movements That Are Precisely Programmed and Monitored A Complex Neural System Controls Muscles to Create Behavior  Muscles and the skeleton work together to move the body  Sensory feedback from muscles, tendons, and joints governs movement  The spinal cord mediates “automatic” responses and receives inputs from the brain  Motor cortex plans and executes movements—and more  RESEARCHERS AT WORK: Mirror neurons in premotor cortex track movements in others  Extrapyramidal systems regulate and fine-tune motor commands  Damage to extrapyramidal systems impairs movement Questions 2) Specialized body components, collectively called sensory receptor organs, are sensitive to energies (stimuli) of various sorts that come into contact with the body. The job of these organs is to convert environmental energy into electrical signals. E x a m 3 S t u d y G u i d e | 7 3) The concept of labeled lines states that particular nerve cells are, at the outset, labeled for distinctive sensory experiences and that the sensory qualities of any particular sensory afferent are predetermined. For instance, activity in the touch receptor pathway can be perceived as touch only. 4) The change in the membrane potential of the receptor cell when it is stimulated is called a(n) generator potential, which in many ways is similar to an EPSP. 5) Work on the Pacinian corpuscles has revealed that they produce a graded electrical potential in response to mechanical stimulation and that the amplitude of this potential is directly proportional to the strength of the stimulus. 6)  Pacinian corpuscles are sensitive to pressure and vibration.  Merkel’s discs are sensitive to touch with high spatial resolution and are slow-adapting.  Meissner’s corpuscles, which probably function using a specialized Na+ channel, are sensitive to texture and are fast-adapting.  Ruffini’s endings are sensitive to stretch.  Free nerve endings are sensitive to heat, pain, and cold 9) Individual somatosensory neurons can be recorded by means of an intracranial recording electrode, while the receptive fields for the cell are mapped by stimulating the periphery (in this case, the skin). Receptive fields on the skin are found to have a(n) concentric center-surround organization: stimulation in the center of the receptive field increases the E x a m 3 S t u d y G u i d e | 8 firing rate of neural impulses generated by the cell, while stimulation in the surround decreases it. 15) In the well-known diagram of the “homunculus,” the somatosensory cortex is arranged as an orderly map of the body surface, and all parts of the body are not represented equally. The most sensitive parts of the body contain the highest densities of receptors and therefore account for larger amounts of the sensory cortex. 20) Peripheral afferents transmit pain information through axons that synapse in the dorsal horns of the spinal cord. The axons cross at the level of the spinal cord, and pain information is transmitted to thalamic nuclei before being processed by cingulate cortex. 22) Inappropriate signaling by pain neurons can give rise to neuropathic pain. An example of this is the phantom limb pain experienced by some people who have lost an arm or a leg. Such pain is difficult to treat, as it involves amplification of the brain’s response to the original injury—an example of neural plasticity. Chapter 7 The Visual System Extends from the Eye to the Brain  The vertebrate eye acts in some ways like a camera  Visual processing begins in the retina  Photoreceptors respond to light by releasing less neurotransmitter  Different mechanisms enable the eyes to work over a wide range of light intensities E x a m 3 S t u d y G u i d e | 9  Acuity is best in foveal vision  Neural signals travel from the retina to several brain regions  The retina projects to the brain in a topographic fashion Neurons at Different Levels of the Visual System Have Very Different Receptive Fields  Photoreceptors excite some retinal neurons and inhibit others  Neurons in the retina and the LGN have concentric receptive fields  RESEARCHERS AT WORK: Neurons in the visual cortex have varied receptive fields  Neurons in the visual cortex beyond area V1 have complex receptive fields and help identify forms  Perception of visual motion is analyzed by a special system that includes cortical area V5 Color Vision Depends on Special Channels from the Retinal Cones through Cortical Area V4  Color is created by the visual system  Color perception requires receptor cells that differ in their sensitivities to different wavelengths  BOX 7.1: Most Mammalian Species Have Some Color Vision  Some retinal ganglion cells and LGN cells show spectral opponency  Some visual cortical cells and regions appear to be specialized for color perception E x a m 3 S t u d y G u i d e | 10 The Many Cortical Visual Areas Are Organized into Two Major Streams Visual Neuroscience Can Be Applied to Alleviate Some Visual Deficiencies  Impairment of vision often can be prevented or reduced  Increased exercise can restore function to a previously deprived or neglected eye Questions 1) Light travels in straight lines until it encounters the cornea, which causes the light to bend in a process known as refraction. As this light enters the eye, it is further modified by the lens, which is able to change its shape due to the ciliary muscles. This process is called accommodation and results in the projection of a sharply focused image on the retina, where the photoreceptors are located. 2) Two types of receptor cells are found in the retina: 1. Rods connect to bipolar cells and produce graded potentials. 2. Cones connect to bipolar cells and produce graded potentials. 3) Four types of intermediate cells are found in the retina: 1. Bipolar cells connect to ganglion cells and produce graded potentials. 2. Horizontal cells connect to receptor cells and produce graded potentials. 3. Amacrine cells connect to bipolar and ganglion cells and produce action potentials. E x a m 3 S t u d y G u i d e | 11 4. Ganglion cells connect to brain cells and produce action potentials 4) The rods are especially involved in the scotopic visual system, which works in dim light and does not give rise to color perception. The cones are especially involved in the photopic visual system, which requires more light but gives highly detailed vision, including color information in many species. 6) The visual system responds to changes in light. In rods, light particles are captured by the photo pigment rhodopsin, causing the photoreceptor to hyperpolarize and release less neurotransmitter. 10) The visual field is the entire area that you can see without moving your head or eyes, but the sharpness of the visual image, known as visual acuity, is far greater toward the center than at the periphery. It is for this reason that we constantly shift our gaze between different objects in the environment. 11) One reason that acuity is heightened in the center of the visual field is the increased density of receptors there, especially cones in the central part of the retina, which is called the fovea. The diameter of photoreceptors is lesser in this location than in the periphery. Some species, such as hawks and eagles, have a much greater density of cones than humans do, and their receptors have a smaller diameter 13) The blind spot is located laterally from the point of fixation for each eye and corresponds to the location at which the optic nerve exits the eye (called the optic disc). In normal vision, the brain fill(s) in this perceptual gap, so it is not noticeable 14) The visual pathway has several major parts: E x a m 3 S t u d y G u i d e | 12  The axons of the ganglion cells of the retina form the optic nerve.  In humans, axons from the nasal retina cross over to the opposite side of the brain at the optic chiasm. Axons from the temporal retina project to their own side of the brain.  Once they enter the brain, the axons of the retinal ganglion cell are called the optic tract.  The axons carrying visual information from the eyes terminate chiefly at the LGN of the thalamus.  Axons from the LGN form a fiber tract called the optic radiations, which terminate(s) at the primary visual cortex. 19) Turning off the light in the center of the receptive fields of off-center bipolar cells causes the receptor cells to release more neurotransmitter, which depolarizes the bipolar cells. Turning on the light in the center of the on-center bipolar cells causes the receptor cells to release less neurotransmitter, which depolarizes the bipolar cells. Vocabulary agonist A molecule, usually a drug that binds a receptor molecule and initiates a response like that of another molecule, usually a neurotransmitter. alcohol A neuroactive compound (primarily the ethyl variety found in various beverages) that first stimulates and then depresses neural activity, with varied behavioral consequences. amine neurotransmitter A neurotransmitter based on modifications of a single amino acid nucleus. Examples include acetylcholine, serotonin, and dopamine. amino acid neurotransmitter A neurotransmitter that is itself an amino acid. Examples include GABA, glycine, and glutamate. amphetamine A molecule that resembles the structure of the catecholamine transmitters and enhances their activity. E x a m 3 S t u d y G u i d e | 13 analgesic Having painkilling properties. antagonist A molecule, usually a drug that interferes with or prevents the action of a neurotransmitter. antidepressant A drug that relieves the symptoms of depression. anxiolytic A drug that is used to combat anxiety. atypical neuroleptic An antipsychotic drug that has actions other than or in addition to the dopamine 2 receptor antagonism that characterizes the typical neuroleptics. barbiturate An early anxiolytic drug and sleep aid that has depressant activity in the nervous system. basal forebrain A region, ventral to the basal ganglia that is the major source of acetylcholine in the brain. benzodiazepine Any of a class of antianxiety drug that are agonists of GABA receptors in the central nervous system. One example is diazepam (Valium). binding affinity or affinity The propensity of molecules of a drug (or other ligand) to bind to receptors. bioavailable Referring to a substance, usually a drug, that is present in the body in a form that is able to interact with physiological mechanisms. biotransformation The process in which enzymes convert a drug into a metabolite that is itself active, possibly in ways that are substantially different from the actions of the original substance. cholinergic Referring to cells that use acetylcholine as their synaptic transmitter. cocaine A drug of abuse, derived from the coca plant that acts by enhancing catecholamine neurotransmission. cross-tolerance A condition in which the development of tolerance for one drug causes an individual to develop tolerance for another drug. delta-9-tetrahydrocannabinol (THC) The major active ingredient in marijuana. dependence In the context of substance-related disorders, the strong desire to self-administer a drug of abuse. To be diagnosed, a person must meet at least three of seven criteria relating to patterns of consumption, craving, expenditure of time and energy in serving the addiction, and impact on other aspects of the person’s life. depressant A drug that reduces the excitability of neurons. dopamine (DA) A monoamine transmitter found in the midbrain—especially the substantia nigra— and in the basal forebrain. E x a m 3 S t u d y G u i d e | 14 dopaminergic Referring to cells that use dopamine as their synaptic transmitter. dose-response curve (DRC) A formal graph of a drug’s effects (on the y-axis) versus the dose given (on the x- axis). down-regulation A compensatory decrease in receptor availability at the synapses of a neuron. drug tolerance A condition in which, with repeated exposure to a drug, an individual becomes less responsive to a constant dose. efficacy or intrinsic activity The extent to which a drug activates a response when it binds to a receptor. endocannabinoid An endogenous ligand of cannabinoid receptors; thus, an analog of marijuana that is produced by the brain. endogenous opioid Any of a class of opium-like peptide transmitters that have been called the body’s own narcotics. The three kinds are enkephalins, endorphins, and dynorphins. endorphin One of the three kinds of endogenous opioids. enkephalin One of the three kinds of endogenous opioids. exogenous Arising from outside the body. fetal alcohol syndrome A disorder, including intellectual disability and characteristic facial abnormalities, that affects children exposed to too much alcohol (through maternal ingestion) during fetal development. functional tolerance The form of drug tolerance that arises when repeated exposure to the drug causes receptors to be up-regulated or down-regulated. gamma-aminobutyric acid (GABA) A widely distributed amino acid transmitter, and the main inhibitory transmitter in the mammalian nervous system. gas neurotransmitter A neurotransmitter that is a soluble gas. Examples include nitric oxide and carbon monoxide. glutamate An amino acid transmitter, the most common excitatory transmitter. hallucinogen A drug that alters sensory perception and produces peculiar experiences. heroin Diacetylmorphine; an artificially modified, very potent form of morphine. insula A region of cortex lying below the surface, within the lateral sulcus, of the frontal, temporal, and parietal lobes. lateral tegmental area A brainstem region that provides some of the norepinephrine-containing projections of the brain. ligand E x a m 3 S t u d y G u i d e | 15 A substance that binds to receptor molecules, such as a neurotransmitter or drug that binds postsynaptic receptors. locus coeruleus A small nucleus in the brainstem whose neurons produce norepinephrine and modulate large areas of the forebrain. LSD Also called acid. Lysergic acid diethylamide, a hallucinogenic drug. marijuana A dried preparation of the Cannabis sativa plant, usually smoked to obtain THC. metabolic tolerance The form of drug tolerance that arises when repeated exposure to the drug causes the metabolic machinery of the body to become more efficient at clearing the drug. morphine An opiate compound derived from the poppy flower. neuroleptics or antipsychotics Any of a class of antipsychotic drugs that alleviate symptoms of schizophrenia, typically by blocking dopamine receptors. neurotransmitter Also called simply transmitter. A signaling chemical, released by a presynaptic neuron, which diffuses across the synaptic cleft to alter the functioning of the postsynaptic neuron. neurotransmitter receptor Also called simply receptor. A specialized protein that is embedded in the cell membrane, allowing it to selectively sense and react to molecules of the corresponding neurotransmitter. nicotine A compound found in plants, including tobacco that acts as an agonist on a large class of cholinergic receptors. noradrenergic Referring to cells using norepinephrine (noradrenaline) as a transmitter. norepinephrine (NE) Also called noradrenaline. A neurotransmitter that is produced and released by sympathetic postganglionic neurons to accelerate organ activity. It is also produced in the brainstem and found in projections throughout the brain. nucleus accumbens A region of the forebrain that receives dopaminergic innervation from the ventral tegmental area. Dopamine release in this region may mediate the reinforcing qualities of many activities, including drug abuse. opioid peptide A type of endogenous peptide that mimics the effects of morphine in binding to opioid receptors and producing marked analgesia and reward. opioid receptor A receptor that responds to endogenous opioids and/or exogenous opiates. opium An extract of the seedpod juice of the opium poppy, Papaver somniferum. Drugs based on opium are potent painkillers. peptide neurotransmitter Also called neuropeptide. A neurotransmitter consisting of a short chain of amino acids. periaqueductal gray E x a m 3 S t u d y G u i d e | 16 The neuronal body–rich region of the midbrain surrounding the cerebral aqueduct that connects the third and fourth ventricles; it is involved in pain perception. postsynaptic Located on the “receiving” side of a synapse. presynaptic Located on the “transmitting” side of a synapse. retrograde transmitter A neurotransmitter that diffuses from the postsynaptic neuron back to the presynaptic neuron. reuptake The reabsorption of molecules of neurotransmitter by the neurons that released them, thereby ending the signaling activity of the transmitter molecules. selective serotonin reuptake inhibitor (SSRI) A drug that blocks the reuptake of transmitter at serotonergic synapses. serotonergic Referring to cells that use serotonin as their synaptic transmitter. serotonin (5-HT) A synaptic transmitter that is produced in the raphe nuclei and is active in structures throughout the cerebral hemispheres. substance abuse A maladaptive pattern of substance use that has lasted more than a month but does not fully meet the criteria for dependence. substantia nigra A brainstem structure that innervates the basal ganglia and is the source of all dopaminergic projections. synapse The location at which information flows between a presynaptic neuron and a postsynaptic neuron, often through the conversion of electrical activity in the presynaptic neuron into a secretion of chemical neurotransmitter that alters the functioning of the postsynaptic neuron. tobacco A highly addictive North American plant whose leaves (usually dried and smoked) are a major source of nicotine. transporter A specialized membrane component that returns transmitter molecules to the presynaptic neuron for reuse. tricyclic antidepressant An antidepressant that acts by increasing the synaptic accumulation of serotonin and norepinephrine. up-regulation A compensatory increase in receptor availability at the synapses of a neuron. ventral tegmental area (VTA) A portion of the midbrain that projects dopaminergic fibers to the nucleus accumbens A delta (Aδ) fiber A moderately large, myelinated, and therefore fast-conducting, axon, usually transmitting pain information. acetylcholine (ACh) A neurotransmitter that is produced and released by parasympathetic postganglionic neurons, by motoneurons, and by neurons throughout the brain. E x a m 3 S t u d y G u i d e | 17 act Complex behavior, as distinct from a simple movement. acupuncture The insertion of needles at designated points on the skin to alleviate pain or neurological malfunction. adaptation The progressive loss of receptor sensitivity as stimulation is maintained. analgesia Absence of or reduction in pain. antagonist A muscle that counteracts the effect of another muscle. anterolateral system or spinothalamic system A somatosensory system that carries most of the pain information from the body to the brain. apraxia An impairment in the ability to carry out complex movements, even though there is no muscle paralysis. ataxia A loss of movement coordination, often caused by disease of the cerebellum. ballistic Referring to a rapid muscular movement that is generally fully preprogrammed and thus not susceptible to error correction during execution. basal ganglia A group of forebrain nuclei, including caudate nucleus, globus pallidus, and putamen, found deep within the cerebral hemispheres. C fiber A small, unmyelinated axon that conducts pain information slowly and adapts slowly. central modulation of sensory information The process in which higher brain centers, such as the cortex and thalamus, suppress some sources of sensory information and amplify others. cerebellum A structure located at the back of the brain, dorsal to the pons that is involved in the central regulation of movement. cingulate cortex Also called cingulum. A region of medial cerebral cortex that lies dorsal to the corpus callosum. closed-loop motor control A control mechanism that provides a flow of information from whatever is being controlled to the device that controls it. decomposition of movement Difficulty of movement in which gestures are broken up into individual segments instead of being executed smoothly; it is a symptom of cerebellar lesions. dermatome A strip of skin innervated by a particular spinal nerve. dorsal column system A somatosensory system that delivers most touch stimuli via the dorsal columns of spinal white matter to the brain. electromyography (EMG) The electrical recording of muscle activity. E x a m 3 S t u d y G u i d e | 18 endorphin One of three kinds of endogenous opioids. extrapyramidal system A motor system that includes the basal ganglia and some closely related brainstem structures. Axons of this system pass into the spinal cord outside the pyramids of the medulla. final common pathway The motoneurons of the spinal cord, so called because they receive and integrate all motor signals from the brain and then direct movement accordingly. free nerve ending An axon that terminates in the skin and has no specialized cell associated with it. Free nerve endings detect pain and/or changes in temperature. generator potential A local change in the resting potential of a receptor cell that mediates between the impact of stimuli and the initiation of action potentials. Golgi tendon organ Any of the receptors within tendons that send impulses to the central nervous system when a muscle contracts. Huntington’s disease A genetic disorder, with onset in middle age, in which the destruction of basal ganglia results in a syndrome of abrupt, involuntary writhing movements and changes in mental functioning. intrafusal fiber Any of the small muscle fibers that lie within each muscle spindle. labeled lines The concept that each nerve input to the brain reports only a particular type of information. Meissner’s corpuscle or tactile corpuscle A skin receptor cell type that detects light touch, responding especially to changes in stimuli. Merkel’s disc A skin receptor cell type that detects light touch, responding especially to edges and isolated points on a surface. mirror neuron A neuron that is active both when an individual makes a particular movement and when that individual sees another individual make the same movement. motoneuron Also called motor neuron. A neuron that transmits neural messages to muscles (or glands). motor plan Also called motor program. A plan for a series of muscular contractions, established in the nervous system prior to its execution. movement A single relocation of a body part, usually resulting from a brief muscle contraction; less complex than an act. muscle spindle A muscle receptor that lies parallel to a muscle and sends impulses to the central nervous system when the muscle is stretched. naloxone E x a m 3 S t u d y G u i d e | 19 A potent antagonist of opiates that is often administered to people who have taken drug overdoses. It binds to receptors for endogenous opioids. neuromuscular junction The region where the motoneuron terminal and the adjoining muscle fiber meet; the point where the nerve transmits its message to the muscle fiber. neuropathic pain Pain that persists long after the injury that started it has healed. It is caused by damage to peripheral nerves and is often difficult to treat. nociceptor A receptor that responds to stimuli (e.g., pain or changes in temperature) that produce tissue damage or pose the threat of damage. nonprimary motor cortex Frontal lobe regions adjacent to the primary motor cortex that contribute to motor control and modulate the activity of the primary motor cortex. nonprimary sensory cortex Also called secondary sensory cortex. For a given sensory modality, the cortical regions receiving direct projections from primary sensory cortex for that modality. open-loop motor control A control mechanism in which feedback from the output of the system is not provided to the input control. Pacinian corpuscle or lamellated corpuscle A skin receptor cell type that detects vibration and pressure. pain The discomfort normally associated with tissue damage. paresis Muscular weakness, often the result of damage to motor cortex. Parkinson’s disease A degenerative neurological disorder, characterized by tremors at rest, muscular rigidity, and reduction in voluntary movement, caused by loss of the dopaminergic neurons of the substantia nigra. phasic receptor A receptor in which the frequency of action potentials drops rapidly as stimulation is maintained. placebo effect Relief of a symptom, such as pain, that results following a treatment that is known to be ineffective or inert. plegia Paralysis, the loss of the ability to move. polymodal neuron A neuron upon which information from different sensory systems converges. precentral gyrus The strip of frontal cortex, just in front of the central sulcus, that is crucial for motor control. premotor cortex A region of nonprimary motor cortex just anterior to the primary motor cortex. primary motor cortex (M1) The apparent executive region for the initiation of movement; primarily the precentral gyrus. primary sensory cortex E x a m 3 S t u d y G u i d e | 20 For a given sensory modality, the region of cortex that receives most of the information about that modality from the thalamus or, in the case of olfaction, directly from the secondary sensory neurons. primary somatosensory cortex or somatosensory 1 (S1) The gyrus just posterior to the central sulcus where sensory receptors on the body surface are mapped. Primary cortex for receiving touch and pain information, in the parietal lobe. proprioception Body sense; information about the position and movement of the body that is sent to the brain. pyramidal system or corticospinal system The motor system that includes neurons within the cerebral cortex and their axons, which form the pyramidal tract. range fractionation The means by which sensory systems cover a wide range of intensity values as each sensory receptor cell specializes in just one part of the overall range of intensities. receptive field The stimulus region and features that affect the activity of a cell in a sensory system. receptor cell A specialized cell that responds to a particular energy or substance in the internal or external environment, and converts this energy into a change in the electrical potential across its membrane. reflex A simple, highly stereotyped, and unlearned response to a particular stimulus (e.g., an eye blink in response to a puff of air). Ruffini corpuscle A skin receptor cell type that detects stretching of the skin. sensory transduction The process in which a receptor cell converts the energy in a stimulus into a change in the electrical potential across its membrane. skeletal muscle A muscle that is used for movement of the skeleton, typically under our conscious control. somatosensory system A set of specialized receptors and neural mechanisms responsible for body sensations such as touch and pain. stimulus A physical event that triggers a sensory response. stretch reflex The contraction of a muscle in response to stretch of that muscle. striate muscle A type of muscle that has a striped appearance; it is generally under voluntary control. substance P A peptide transmitter that is involved in pain transmission. substantia nigra A brainstem structure in humans that innervates the basal ganglia and is named for its dark pig-mentation. E x a m 3 S t u d y G u i d e | 21 supplementary motor area (SMA) A region of nonprimary motor cortex that receives input from the basal ganglia and modulates the activity of the primary motor cortex. synergist A muscle that acts together with another muscle. synesthesia A condition in which stimuli in one modality evoke the involuntary experience of an additional sensation in another modality. thalamus The brain regions at the top of the brainstem that trade information with the cortex. threshold The stimulus intensity that is just adequate to trigger an action potential at the axon hillock. tonic receptor A receptor in which the frequency of action potentials declines slowly or not at all as stimulation is maintained. transcutaneous electrical nerve stimulation (TENS) The delivery of electrical pulses through electrodes attached to the skin, which excite nerves that supply the region to which pain is referred. TENS can relieve the pain in some instances. transient receptor potential 2 (TRP2) A receptor, found in some free nerve endings, that opens its channel in response to rising taccommodation The process by which the ciliary muscles adjust the lens to focus a sharp image on the retina. amacrine cell A specialized retinal cell that contacts both bipolar cells and ganglion cells, and is especially significant in inhibitory interactions within the retina. amblyopia Reduced visual acuity that is not caused by optical or retinal impairments. binocular Two-eyed. bipolar cell An interneuron in the retina that receives information from rods and cones and passes the information to retinal ganglion cells. blind spot The portion of the visual field from which light falls on the optic disc. Because there are no receptors in this region, light striking the blind spot cannot be seen. blindsight The paradoxical phenomenon whereby, within a scotoma, a person cannot consciously perceive visual cues but may still be able to make some visual discrimination. brightness One of three basic dimensions of light perception, varying from dark to light. ciliary muscle One of the muscles that control the shape of the lens inside the eye, focusing an image on the retina. complex cortical cell A cell in the visual cortex that responds best to a bar of a particular size and orientation anywhere within a particular area of the visual field. E x a m 3 S t u d y G u i d e | 22 cone Any of several classes of photoreceptor cells in the retina that are responsible for color vision. convergence The phenomenon of neural connections in which many cells send signals to a single cell. cornea The transparent outer layer of the eye, whose curvature is fixed. The cornea bends light rays and is primarily responsible for forming the image on the retina. extraocular muscle One of the muscles attached to the eyeball that control its position and movements. extrastriate cortex Visual cortex outside of the primary visual (striate) cortex. fovea The central portion of the retina, which is packed with the highest density of photoreceptors and is the center of our gaze. ganglion cell Any of a class of cells in the retina whose axons form the optic nerve. horizontal cell A specialized retinal cell that contacts both receptor cells and bipolar cells. hue One of three basic dimensions of light perception, varying around the color circle through blue, green, yellow, orange, and red. iris The circular structure of the eye that provides an opening to form the pupil. lateral geniculate nucleus (LGN) The part of the thalamus that receives information from the optic tract and sends it to visual areas in the occipital cortex. lateral inhibition The phenomenon by which interconnected neurons inhibit their neighbors, producing contrast at the edges of regions. lens A structure in the eye that helps focus an image on the retina. myopia Nearsightedness; the inability to focus the retinal image of objects that are far away. occipital cortex Also called visual cortex. The cortex of the occipital lobe of the brain. off-center bipolar cell A retinal bipolar cell that is inhibited by light in the center of its receptive field. off-center ganglion cell A retinal ganglion cell that is activated when light is presented to the periphery, rather than the center, of the cell’s receptive field. off-center/on-surround Referring to a concentric receptive field in which stimulation of the center inhibits the cell of interest while stimulation of the surround excites it. on-center bipolar cell A retinal bipolar cell that is excited by light in the center of its receptive field. on-center ganglion cell A retinal ganglion cell that is activated when light is presented to the center, rather than the periphery, of the cell’s receptive field. E x a m 3 S t u d y G u i d e | 23 on-center/off-surround Referring to a concentric receptive field in which stimulation of the center excites the cell of interest while stimulation of the surround inhibits it. opponent-process hypothesis A hypothesis of color perception stating that different systems produce opposite responses to light of different wavelengths. optic ataxia Spatial disorientation in which the patient is unable to accurately reach for objects using visual guidance. optic chiasm The point at which the two optic nerves meet. optic disc The region of the retina that is devoid of receptor cells because ganglion cell axons and blood vessels exit the eyeball there. optic nerve Cranial nerve II; the collection of ganglion cell axons that extend from the retina to the brain. optic radiation Axons from the lateral geniculate nucleus that terminate in the primary visual areas of the occipital cortex. optic tract The axons of retinal ganglion cells after they have passed the optic chiasm; most of these axons terminate in the lateral geniculate nucleus. photopic system A system in the retina that operates at high levels of light, shows sensitivity to color, and involves the cones. photoreceptor adaptation The tendency of rods and cones to adjust their light sensitivity to match ambient levels of illumination. photoreceptor A neural cell in the retina that responds to light. primary visual cortex (V1) or striate cortex Also called area 17. The region of the occipital cortex where most visual information first arrives. pupil The opening, formed by the iris that allows light to enter the eye. range fractionation The means by which sensory systems cover a wide range of intensity values, as each sensory receptor cell specializes in just one part of the overall range of intensities. receptive field The stimulus region and features that affect the activity of a cell in a sensory system. refraction The bending of light rays by a change in the density of a medium, such as the cornea and the lens of the eyes. retina The receptive surface inside the eye that contains photoreceptors and other neurons. rhodopsin E x a m 3 S t u d y G u i d e | 24 The photopigment in rods that responds to light. rod A photoreceptor cell in the retina that is most active at low levels of light. saturation One of three basic dimensions of light perception, varying from rich to pale. scotoma A region of blindness within the visual fields, caused by injury to the visual pathway or brain. scotopic system A system in the retina that operates at low levels of light and involves the rods. simple cortical cell Also called bar detector or edge detector. A cell in the visual cortex that responds best to an edge or a bar that has a particular width, as well as a particular orientation and location in the visual field. spatial-frequency model A model of vision that emphasizes the analysis of different spatial frequencies, of various orientations and in various parts of the visual field, as the basis of visual perception of form. spectrally opponent cell A visual receptor cell that has opposite firing responses to different regions of the spectrum. topographic projection A mapping that preserves the point-to-point correspondence between neighboring parts space. For example, the retina extends a topographic projection onto the cortex. transduction The conversion of one form of energy to another, as converting light into neuronal activity. trichromatic hypothesis A hypothesis of color perception stating that there are three different types of cones, each excited by a different region of the spectrum and each having a separate pathway to the brain. visual acuity Sharpness of vision. visual field The whole area that you can see without moving your head or eyes. wavelength The length between two peaks in a repeated stimulus such as a wave, light, or sound temperatures. Study Questions 1. Discuss 3 major functional classes of drugs: antipsychotics, antidepressants, and anxiolytics. For each class, identify what they are used for and their functional effects (what exactly do they do). E x a m 3 S t u d y G u i d e | 25 2. Briefly describe the differences between opiates, cannabinoids, alcohol, stimulants, and hallucinogens. Which drugs are included in each class and what does each do? 3. Why is alcohol "special"; what makes it different from other drugs? Discuss what occurs with long term alcohol use. 4. Identify some of the factors that predispose some individuals to abuse drugs and describe some of the treatments that have been devised to help treat substance-related disorders. 5. Trace the neural signal from a Pacinian corpuscle to the cortex and the neural signal from free nerve endings to the cortex. Where do you think the signal goes from there? 6. Survey the mechanisms by which drugs can alter presynaptic and postsynaptic function. If given a particular mechanism, could you tell me whether it was presynaptic or postsynaptic? Can you identify these structures and be able to tell the difference? 7. Fill out the following 2 diagrams of the eye and the retina by identifying structures and naming at least one function of each. Do the different retinal layers generate graded potentials or action (all-or-none) potentials? Can you trace the signals coming from the retina and going through to the cortex? Are the signals ipsilateral or contralateral? Exam 1 Study Guide Chapter 1 Questions 1) Another name for biological psychology is: a. Physiological psychology b. Behavioral neuroscience c. Brain and behavior d. All of the above 10) The popular nineteenth-century field of PHRENOLOGY was based on the notion that the behavior of individuals can be predicted from the pattern of lumps and bumps on the skull. Other investigators rejected this notion, arguing instead that the brain operates as a whole, without any LOCALIZATION of functions to specific regions. We know now that although the whole brain is active in most behavior, peaks of activity are seen in different locations depending on the task being performed. 21) The term “neuroplasticity” refers to the ability of the brain to be changed by EXPERIENCE. These changes may involve alterations in the number or size of neurons or neural connections. 22) NEUROGENESIS refers to the creation of new neurons in the brain of an adult. 33) 1) Training animals in a maze and recording physiological changes in their brains— behavioral intervention 2. Stimulating a brain structure and recording subsequent changes in movement— somatic intervention 3. Introducing two adults of the opposite sex and then measuring their hormone levels— behavioral intervention 4. Measuring the brain volumes and intelligence of a group of people— correlation 5. Observing enlarged cerebral ventricles in the brains of many people with schizophrenia— correlation 6. Severing the connections between visual regions and the rest of the brain in animals and observing the animals’ failure to recognize objects— somatic intervention 7. Studying the relationship between a hormone treatment and strength of an animal’s mating behavior— somatic intervention 34) In the correlation approach, the scientist is looking at how particular bodily measures vary with particular behaviors, while manipulating neither body structure nor behavior. This approach cannot establish causal relationships. 35) For the following levels of analysis, select the numbers that would place them in order from the most complex level of analysis to the least complex:  7 Synaptic level  3 Neural systems level  4 Brain region level  8 Molecular level  2 Organ level  1 Social level  6 Cellular level  5 Circuit level 36) The scientific approach that involves analysis at a simpler or more basic level of organization than the structure or function to be explained is called reductionism. Although there are practical limits to this approach, it is the basis of most modern science. Chapter 13 37) The production of nerve cells is called neurogenesis. Although neurons themselves do not divide, the cells that become neurons reproduce through a process called mitosis and form a closely packed zone of cells called the ventricular zone. 38) 1. Synapse rearrangement refers to the loss of some synapses and formation of others. 2. Synaptogenesis is the establishment of connections between neurons and other cells. 3. Neurogenesis is the birth of new neurons from nonneuronal cells. 4. Neuronal cell death refers to the selective demise of many neurons. 5. Cell differentiation is the transformation of new cells into distinctive neuron types. 6. Cell migration refers to the massive movement of nerve cells to new locations. Chapter 2 1) Although many anatomists in the early days of neuroscience believed that neurons were continuous with one another, forming a system of tubes, Santiago Ramón y Cajal argued convincingly that they are contiguous, that is, close together but not joined. We now know that the human brain contains about 100–150 billion discrete neurons. 2) The neuron doctrine consists of two basic premises. The first is that the brain is composed of neurons and other cells that are independent from (with) one another. The second is that information is transmitted between cells across tiny gaps called synapses. 3) Most neurons possess three major parts: the dendrites (input); the axon (output); and the cell body (integration zone, containing the nucleus). Neurons are very small and have tiny processes of 1–3 μm in diameter, which makes them difficult to study. 6) Neurons can be classified on the basis of shape. Bipolar neurons have a single dendrite and a single axon and are found in the retina. Multipolar neurons have multiple dendrites and are the most common class of neuron. Unipolar neurons have a single branch extending in two directions and are part of the system mediating touch. 9) Microglia are very small and mobile, and they serve to remove debris from sites of injury. 10) The components of a synapse are listed below in no particular order. By choosing the appropriate number from 1 to 7, indicate the sequence in which these structures are involved in transmitting information. Brief questions follow.  1 Axon. This is the output zone of the presynaptic cell.  6 Postsynaptic membrane. This contains the receptors for neurotransmitters.  2 Synaptic bouton. This is located at the end of the axon.  4 Neurotransmitter substance. A chemical that produces changes in the postsynaptic membrane.  7 Dendrite. This is the input zone of the postsynaptic cell.  5 Synaptic cleft. This is approximately 20–40 nm in width.  3 Synaptic vesicles. These contain molecules of neurotransmitter. 13) Axons frequently are sheathed in myelin, which contributes to the conduction of nerve impulses along the axon. This process of myelination is performed by oligodendrocytes in the brain and spinal cord and by Schwann cells outside the brain and spinal cord. The gaps that are found between adjacent segments of myelin on an axon are called nodes of Ranvier. Chapter 3 1) Like other bodily cells, the neuron under steady state conditions exhibits a slight electrical difference between the inside of its cell membrane and the outside. This is known as the resting membrane potential. This potential is attributable to differential concentrations of ions inside the cell relative to the outside, and is about –50 to –80 millivolts in magnitude. 2) Positively charged ions are called cations, while negatively charged ions are called anions. Since the inside of a resting cell is negative relative to the outside, cations on the outside of the cell will be attracted to the intracellular fluid and anions will be repelled by it. 3) A second force that helps determine the distribution of ions is the concentration gradient, which refers to the propensity of ions to move from regions of high concentration to areas of low concentration. Neuronal membranes exhibit selective permeability, which means that the types of ion channels present in the membrane determine the types of ions that can be moved by these forces through the cell membrane. Neurons at rest are selectively permeable to potassium. 4) The neuronal cell membrane is a lipid bilayer that repels water; this property necessitates the production of ion channels. Ions are surrounded by water, and therefore they can enter the cell only through a channel with properties different from those of the cell membrane. 5) The presence of large anions within a neuron creates a negative charge that tends to pull potassium ions into the cell. However, there are already about 5 times as many potassium ions inside the neuron as there are outside, so the concentration gradient tends to push potassium ions out of the cell. Eventually the two forces are exactly balanced, yielding the neuron’s resting potential, which corresponds to the potassium equilibrium potential, in the range of –50 mV to –80 mV. 6) The cell employs sodium–potassium pumps to actively counter leakage of Na+ ions into the neuron; if it did not, the cell’s resting potential would eventually be at 0 mV. 8) The generation of an action potential is critically dependent on voltage- gated Na+ channels. At threshold depolarization these channels start to open, and the depolarization caused by the entry of Na+ into the axon causes still more voltage-gated channels to open, until Na+ floods in and causes the membrane potential to suddenly become positive. The sodium channels are open for a little less than 1 ms. Positive charges inside the cell then push K+ ions out and the resting potential is rapidly restored, although brief oscillations called after-potentials are observed. 9) A stimulus applied to a neuronal membrane that causes its potential to become more positive is a depolarization. A stimulus that moves the potential closer to 0 is a depolarization. 11) State of gated K+ State of Na + Membrane state channels channels Resting closed closed Depolarization closed some open Threshold depolarization and action potential generated closed many open Action potential collapses open closed Return to resting closed closed 15) The refractory phase is the period of time following the firing of an action potential during which another action potential cannot be fired. During the absolute refractory period, no action potential can occur, no matter how strong the depolarizing stimulation is. During the relative refractory period, an action potential may be fired, but only if the depolarization far exceeds the normal threshold. Refractoriness limits the frequency of action potentials to about 1000 per second. 17) Invertebrate axons lack myelination, and instead rely on large- diameter axons to carry action potentials quickly. When an action potential arrives at the axon terminal of an excitatory presynaptic neuron, a local, graded depolarization, known as a(n) EPSP, is produced in the postsynaptic cell. If the presynaptic cell is inhibitory, then an IPSP is produced on the postsynaptic cell instead, generally as a consequence of the opening of Cl– channels. The decision to produce an action potential generally depends on the effect of numerous EPSPs and IPSPs working together. Whether or not a synapse produces an IPSP or an EPSP generally depends on the particular transmitter used by that synapse. 19) Imagine a simplified neuron (lacking dendrites) with four synapses on the cell body—two inhibitory and two excitatory. A pattern of firing that would provide the maximal likelihood of producing an action potential would be rapid repeated firing at all excitatory synapses with no firing at inhibitory synapses, thus maximizing the likelihood of a threshold depolarization. 22) Incoming information, in the form of a graded potential is integrated in the postsynaptic neuron through the process of summation. There are two mechanisms by which this occurs: 1. Temporal summation is the addition of two potentials that occur close together in time. 2. Spatial summation is the addition of two potentials that occur close together physically on the cell membrane. 23) For the following items, select the numbers that would place the events in the correct order:  5 A graded potential (EPSP or IPSP) spreads toward the axon hillock.  4 Postsynaptic receptors respond by opening ion channels.  6 Synaptic transmitter is rapidly inactivated.  1 Presynaptic action potential propagates to the axon terminal.  7 Neurotransmitters are removed rapidly from the synaptic cleft by transporters.  3 Calcium influx induces synaptic vesicles to fuse to the presynaptic membrane.  2 Voltage-gated calcium channels open. 27) There are two major mechanisms for clearing neurotransmitter from the synaptic cleft: enzymatic degradation and neuronal reuptake. In neuronal reuptake, special receptors on the presynaptic membrane called transporters remove molecules of neurotransmitter from the synapse. Lecture and Textbook Study Questions 1) What is meant by the statement “interactions between the brain and behavior are reciprocal”? a. Brain controls behavior and behavior alters the brain 2) There are 5 major research perspectives used in biological psychology. a. Description i. Structural: Pav’s Dog; conditioning; If we do this, this happens; How are the sounds of speech patterned? ii. Functional: How do certain behaviors lead to seeking rewards or avoidance of punishment? What behavior is involved in making statements or asking questions? b. Evolutionary i. Evolution c. Mechanisms i. Anything related to physical parts of the body d. Application i. How does treatment/medication/therapy affect this? e. Development i. How do children learn how to speak? ii. How does memory change over one’s lifetime?  memory change over one’s lifetime? 3) 3 Approaches to understand brain and behavior o Somatic  Administer a hormone strength of mating behavior o Behavioral  Male next to femalechanges in hormone levels o Correlations  Brain sizelearning scores  Hormone levels strength of mating behavior 4) What are the differences between phrenology and the way we now think of localization of brain function? a. phrenology i. The belief that bumps on the skull reflect enlargements of brain regions responsible for certain behavioral faculties b. localization of function i. The concept that different brain regions specialize in specific behaviors 5) Describe the development of the brain starting with the neural tube. 6) Glia and neurons are cells that make up the nervous system. Describe the various types of glia, where they located (CNS or PNS)) and their functions. a. Glia b. Radial cells*: not really glia i. They’re stem cells ii. Now referred as radial cells iii. Responsible for cell birth iv. Process also involved in migration c. Microglia and macrophages i. Very small ii. From immune cells, NOT brain cells iii. Work’s as the brain’s immune system iv. Many migrate in during the development phase v. Many come in through the blood vi. Help in a case of injury vii. Microglia develop into macrophages d. Ependymal cells i. Line the ventricles and spinal cord e. Macroglia in peripheral nervous system (PNS) i. Satellite cells: line the surface of neurons; maintain chemical milieu ii. Schwann cells: from myelin sheath on axons in PNS; similar to oligodendrocytes in CNS; one Schwann=one neuron; phagocytic f. Macroglia in central nervous system (CNS= brain and spinal cord) i. Astrocytes: large; numerous processes; aid in uptake/breakdown of neurotransmitters; involved in BBB (astrocytic “foot processes”); receive synapses; communicate with themselves and neurons; modify neuronal transmission (ionic milieu) ii. Olidendrocytes: very small; few processes; form myelin sheath on axons in CNS; one oligo and multiple neurons 7) Describe the propagation of a nerve impulse starting with the release of neurotransmitters from the presynaptic membrane.  Cell body: soma; nucleus and other components  Dendrites: receive info from other neurons  Axon Hillock: inputs are integrated (“summed” up)  Axon: single extension away from the soma; sends electrical signal away from the soma  Nodes of Ranvier: increase speed of transmission  Axon terminals: boutons; communicate signals to other cells  Synapses: o Info travels across synapses; from presynaptic neuron to postsynaptic neuron o Presynaptic neuron:  Presynaptic terminal/bouton; presynaptic membrane; synaptic vesicles; neurotransmitters (packaged) o Synaptic cleft: neurotransmitters (released) enzymes (degradation) o Postsynaptic neuron: postsynaptic membrane (included receptors here)  When a neuron fires: o Impulse travels down the axon of the presynaptic neuron o Vesicles move to then fuse with the presynaptic membrane= EXOCYTOSIS o Fusing results in spilling neurotransmitters into synaptic cleft o Neurotransmitters are taken up by receptors in postsynaptic membrane  3 Principle Types of Neurons o Multipolar  Many dendrites, single axon  Most common o Bipolar  Single dendrite at one end and single axon at the other end  Common in sensory systems


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