psych 202: exam 2

EXAM 2 • Exogenous vs endogenous • Glutamate • GABA • Acetylcholine o Basal forebrain • Dopamine o Ventral tegmental area o Substantia nigra • Serotonin o Raphe nuclei • Norepinephrine o Locus coeruleus • Retrograde transmitters • Drug effects on... o transmitter production o transmitter release o transmitter clearance o receptor activity o postsynaptic activity o Note: for above terms, understand general mechanisms of how drugs can affect each stage, and how a drug could be an agonist or antagonist at each stage. That is, learn general mechanisms but not all specific drug examples from book. • Antipsychotics • Monoamine oxidase (MAO) inhibitors • Selective serotonin reuptake inhibitors (SSRIs) • Benzodiazepines • Morphine • Heroin • Endogenous opioids • Caffeine • Cannabis • Endocannabinoids • Nicotine • Cocaine • Amphetamine • Alcohol • LSD • MDMA Sensory Systems (Ch 6) • Decibels • Hertz • Transduction • Eardrum • Ossicles • Middle ear • Oval window • Inner ear • Cochlea • Basilar membrane • Inner hair cells • Tectorial membrane • Stereocilia • Mechanism of transduction • Inferior colliculi • Medial geniculate nuclei (MGN, thalamus) • Tonotopic organization • Place coding • Temporal (rate) coding • Interaural intensity (loudness) differences • Sound shadow • Interaural temporal (latency) differences • Conduction deafness • Sensorineural deafness • Central deafness • Cochlear implants • Vestibular system • Semicircular canals • Five basic tastes • Flavors (definition: taste + smell) • Taste buds • Taste receptor cell • Taste map of tongue (myth) • Approximate lifespan of taste cells (minutes or days or weeks or years) • Olfactory epithelium • Olfactory receptor cells (aka olfactory sensory neurons) • Olfactory receptor proteins Vision (Ch 7) • Retina • Lens • Ciliary muscles • Accommodation • Myopia • Photoreceptors • Rods • Cones • Bipolar cells • Ganglion cells • Optic nerve • Scotopic system • Photopic system • Rhodopsin • Hyperpolarization in response to light • Photoreceptor adaptation • Visual acuity • Fovea • Optic disc • Blind spot • Occipital cortex • Optic chiasm • Lateral geniculate nucleus (LGN) • Visual pathways in human brain • Visual field • Topographic projection (aka retinotopic mapping) • Blindsight • Receptive field • Context effects on perception of brightness • Striate cortex (V1) • Extrastriate cortices • Form and movement in higher cortical areas • What and where pathways - eye anatomy & function - pupil: opening formed by the ***iris***, allows light to enter eye - LGN & cortical cells - lateral geniculate nucleus (LGN): relay station between eye ↔ visual cortex, receives input from ***ganglion cells of the retina*** - spectral (color) opponent cell: has opposite firing responses to different regions of the spectrum - visual cortical cells: require more-specific, elongated stimuli (*compared to LGN or ganglion cells*) - simple (bar detector or edge detector): ****responds best to an edge or a bar that has a particular width, has particular orientation and location in visual field - complex: have elongated receptive fields, but they also require movement of the stimulus to make them respond actively - areas - area v1: primary visual cortex, responsible for basic visual features like edges, orientation, and contrast - area v2: Processes more complex features, integrating contours, textures, and depth - area v3: Involved in processing motion, 3D shapes, and dynamic scenes - area v4: Specializes in color and form, important for object recognition - area v5: Motion perception; specialized in detecting movement and visual processing of speed and direction - on/off-center cells - on-center ganglion cells: activated when light is presented to the center of the cell’s receptive field - when light is turned on, on-center bipolar cells depolarize (excite) - off-center ganglion cells: activated when light is presented to the periphery of the cell’s receptive field - when light is turned off, off-center bipolar cells depolarize (excite)  - visual analysis models - hierarchical: more-complex receptive fields are built up from inputs of simpler ones - e.g., a *simple cortical cell** can be thought of as receiving input from a row of LGN cells with circular receptive fields* - e.g., a *complex cortical cell** can be thought of as receiving input from a row of simple cortical cells* - spatial-frequency: analyzes the number of cycles of light-dark (or color) patches in any stimulus - dimensions of color perception 1. Brightness, which varies from dark to light 2. Hue, which varies continuously through blue, green, yellow, orange, and red (and is what most people mean when they use the term color) 3. Saturation, which varies from rich, full colors to gray; for example, rich red through pink to gray as saturation decreases - processing streams - ventral: responsible for visually identifying objects - dorsal: responsible for appreciating the spatial location of objects (and for visually guiding our interactions with them) - visual impairments - macular degeneration: degeneration of the retinal fovea, impairing vision in the center of the visual field - “**dry” macular degeneration**, is caused by atrophy of the retinal pigmented epithelium, resulting in death of overlying photoreceptors - “wet” macular degeneration, abnormal growth of retinal capillaries leads to detachment of the retina and/or death of photoreceptors - amblyopia: acuity is poor in one eye, even though the eye and retina are normal - optic ataxia: Spatial disorientation in which the person is unable to accurately reach for objects using visual guidance - vision: major themes - Sensation requires transduction: each of our sensory systems has specialized receptors to convert energy in the world into neural signals - photoreceptors sends info about light → graded signals → bipolar cells - bipolar cells send info about light → graded signals → ganglion cells - ganglion cell axons make up → action potentials → optic nerve - optic nerve cross at the → optic chiasm - photoreceptors: send info about light → bipolar cells → ganglion cells - transduction: - rhodopsin: photopigment receptor molecules; on rods - darkness: Glu fires 1. Na+ VG channels open (cell depolarizes) 2. Ca+ channels open 3. Glu is released - light: Glu is inhibited 1. Na+ VG channels close (cell hyperpolarizes) 2. Ca_ channels closed 3. less or no Glu is released - rods: no color, low acuity, high light sensitivity (needs less light) - cones: color, detail (high acuity), low light sensitivity (needs more light)  - adaptation (light ↔ dark) - light → darkness: photopigments on rods need time to regenerate - dar**kness → light**: all photopigments broken down, cones recover quickly - cell preferences - where are cells sensitive? - visual field: everything eyes can see - receptive field: everything one cell can see; a portion of visual field - what do cells care about? - optic disc (blind spot): no ***photoreceptors*** present; where ***optic nerve*** leave the eye - Sensation is selective: sensory receptors are tuned to specific stimuli (and miss others); sensory receptors are most sensitive to change  cones on the absorb/wave spectrum  color visions: deuteranopia, protanopia, & tritanopia - Perception is integrative: sensory information is processed in parallel; our sensory systems interact and influence the perception of each other (sensory interaction) - Perception is affected by cognition (attention and expectation) - wednesday - optic signal 1. optic chiasm → optic tract 2. optic tract → LGN 3. lateral geniculate nucleus (LGN) → primary visual cortex (V1) 4. V1 → extrastriate cortices (V2-V5) --- - optic nerve: between eye and chiasm - optic tract: bundle of axons - optic chiasm: crossing of visual nerves - NOTE: both eyes see the left & visual fields - left visual field → processed in → right visual cortex - right visual field → processed in → left visual cortex [CamScanner 02-12-2025 10.49.pdf](attachment:27fcd946-14c7-4fff-9f86-4880ef94f047:CamScanner_02-12-2025_10.49.pdf) - dorsal and ventral streams - dorsal: where pathway - i.e., *V5**: motion* - ventral: what pathway - i.e., *V4**: color* - - thursday - perceptual constancy: perceiving things to eb the same, despite a change in their shape, brightness, size, etc. - e.g., a person from the back of a room (small) coming to the front (big) and still perceiving them as the same person - basics of sounds - pure tone: tone with single frequency of vibration (aka ***sine wave***) - amplitude (intensity): force exerted by sound; ***loudness*** (dyn/cm2) - frequency: cycles (per second) of a sound wave; ***pitch*** (Hz) - fundamental frequency: basic frequency - harmonics: multiples of ***fundamental frequencies*** - ear anatomy and function - outer ear: directs sound into the inner parts of the ear - transduction: mechanical force (from sound waves) converted → neural activity (AP → brain) - middle ear - tympanic membrane (eardrum): membrane between ***external → middle ear***; reverberates sound waves - ossicles (3 bones): transmit vibration across from the ***tympanic membrane → middle ear → oval window*** - incus (anvil): - malleus (hammer): - stapes (stirrup): - oval window: opening from ***middle → inner ear*** - inner ear - cochlea (3 canals) 1. scala vestibuli: - 2. scala media: receptor system (***organ of Corti***); converts sound waves → neural signal - hair cells: auditory, sensory cells; bridge ***basilar membrane ↔ tectorial membrane*** - framework of supporting cells - auditory nerve terminals: transmit neural signals ↔ brain 1. scala tympani: - vestibular system: detects balance; consists of several small inner-ear structures that adjoin the ***cochlea***  - semicircular canals: 3, fluid-filled canals on different planes (*i.e., pitch, yaw, and roll*) - saccule bulb: - utricle bulb: - interaural differences - interaural intensity differences (IIDs): comparison of sound intensity (*loudness*) between the left and right ears - i.e., one ear is pointed more directly toward the sound source or because the head casts a *sound shadow*** - sound (head) shadow: preventing sounds originating on one side (***off-axis sounds***) from reaching both ears with equal loudness - interaural temporal differences (ITDs): differences between the two ears in the time of arrival of sounds - i.e., one ear is always closer to an off-axis sound - onset disparity: difference between the two ears in hearing the beginning of the sound - ongoing phase disparity: continuing mismatch between the two ears in the time of arrival - deafness - conduction: ears fail to convert sound vibrations in air into waves of fluid in the ***cochlea***; associated with defects of the external ear or middle ear - sensorineural: caused by the permanent damage or destruction of hair cells or by interruption of the ***vestibulocochlear nerve*** - tinnitus: persistent sensation of noises or ringing in the ears not caused by external sound - cochlear implant: detects sounds and then directly stimulate the auditory nerve fibers of the cochlea, bypassing the ***ossicles*** and ***hair cells*** altogether - - offers partial restoration of hearing even in cases of complete ***sensorineural deafness*** - central: failure to process and interpret AP from sound stimuli (*usually as a consequence of damage*) - word deafness: specific inability to hear words although other sounds can be detected - cortical deafness: difficulty in recognizing all complex sounds, whether verbal or nonverbal (*usually caused by damage*) - sound: pressure wave of molecules - sound wave properties (pitch & volume) - amplitude: how tall? - taller: loud voice - shorter: quiet voice - wavelength: how long? - longer = low-pitched voice - shorter = high-pitched voice [CamScanner 02-03-2025 10.44.pdf](attachment:173799fd-b00f-42f4-9dd3-2a21e78888d9:CamScanner_02-03-2025_10.44.pdf) - sound wave characteristics (what & where) - frequency detection: what is it? - **place coding: unrolling the cochlea (where/which cells)** **when each part of the cochlea detects its corresponding frequency, they move/vibrate* - basal end: narrower, detects high frequencies, vibrates stiff frequencies - apical end: wider, detects low frequencies, vibrates flexible frequencies [CamScanner 02-03-2025 11.15.pdf](attachment:cd5873b2-de41-4672-9463-5df296a2ae40:CamScanner_02-03-2025_11.15.pdf)  - **temporal coding (how fast)** **rate of firing of auditory nerve neurons coes Hz for low-freq sounds* - priming: the brain uses existing info and precise neuro pathways to focus its attention - e.g., being able to focus on listening to your friend at a noisy party - localization (where is it): interaural/between ears differences - **interaural (loudness/intensity) differences** **intensity differences only applicable for high freq sounds* - head shadow: only for high frequency sounds - interaural (time) differences - transduction: translating sensory signal → neural signals - e.g., air pressure → neural signals - hair cells (stereocilia): [**hair cells:** translates mechanical signals → neural signal](attachment:233f4b8c-8fd2-4b59-abf6-4b9d90967ee9:CamScanner_02-03-2025_10.52.pdf) hair cells: translates mechanical signals → neural signal [**note**: movement of cilia (from ar/sound waves traveling through ear structure) pulls open K+ MG channels → hair cells depolarize → Ca2+ VG channels open ****→ releases ***NT (glutamate)*** → signals to brain](attachment:37427a3c-6f3a-49f2-aa9c-70b28f82da91:CamScanner_02-03-2025_11.04.pdf) note: movement of cilia (from ar/sound waves traveling through ear structure) pulls open K+ MG channels → hair cells depolarize → Ca2+ VG channels open ****→ releases ***NT (glutamate)*** → signals to brain - ear anatomy [**note**: air/sound waves physi*c*ally move ear drum (producing signal); no translation needed](attachment:05<phone>-4751-adc4-2537e9833e5d:CamScanner_02-03-2025_10.54.pdf) note: air/sound waves physi*c*ally move ear drum (producing signal); no translation needed [**note**: air/sound waves move from eard**r**um → oval window](attachment:902334c4-ddd1-48df-b4e2-8567f3bd153a:CamScanner_02-03-2025_10.57.pdf) note: air/sound waves move from eard**r**um → oval window [**note**: fluid under the flexible, basilar membrane makes it move, further traveling the air/sound waves (this movement reaches the hair cells)](attachment:4a2ddc97-0817-443c-9e4f-dec98ce9ae05:CamScanner_02-03-2025_10.58.pdf) note: fluid under the flexible, basilar membrane makes it move, further traveling the air/sound waves (this movement reaches the hair cells) - tuesday - hearing loss/deafness - conduction deafness: usually middle ear - sensorineural deafness: usually cochlea - central deafness: auditory brain structures  - wednesday - cochlear implant: provide a representation of sounds and can help with understanding speech - can be used in cases of destroyed hair cells, being born without ossicles, etc. - gustation (taste) - toothpaste: decreased sweet receptors, increased bitter receptors - e.g., after brushing teeth: sweet orange juice → bitter orange juice - basic tastes (5) 1. sweet 2. salty 3. bitter 4. sour 5. savory (umami) - taste vs flavor - flavor: sensory integration (affects how we experience food and flavor) - e.g., taste, smell, sight, touch/texture, thoughts - tongue anatomy - papillae: bumps of the tongue - taste bud: little clusters on each papilla - taste receptor cell (TRC): cluster of cells on each taste bud - microvilli: hairlike extensions on each ***TRC***; contains receptors that binds to chemicals (neural signal for detecting taste) **each TRC responds to a different taste type* [**figure B** is unlikely, figure A is most likely](attachment:67454c55-7b1f-4de9-936e-35af8f83f6f7:CamScanner_02-05-2025_11.05.pdf) figure B is unlikely, figure A is most likely - olfaction (smell) - thursday [CamScanner 02-06-2025 10.42.pdf](attachment:f7caabbd-0e1a-485b-9727-e<phone>5:CamScanner_02-06-2025_10.42.pdf) - olfactory neurons: only neuron on the body that gets regularly replaced - **olfactory bulb →** **made up of axons* - olfactory receptor cells - → olfactory cilia: dendritic extensions off of receptor cells mucosa - → olfactory tract [CamScanner 02-06-2025 10.45.pdf](attachment:15aee153-da9d-402c-9887-cd9ed9df6527:CamScanner_02-06-2025_10.45.pdf) - → primary olfactory cortex - → amygdala (limbic system) - vomeronasal organ (VNO): detects pheromones (*influences the social responses of other animals in same species*) - friday: quiz - place coding: detecting the frequency of a sound - temporal coding: firing rate of auditory neurons to match frequency of sounds - excitatory & inhibitory synapses - excitatory: makes postsynaptic neuron more likely to generate an AP - e.g., EPSP - inhibitory: makes postsynaptic neurons less likely to generate an AP - e.g., IPSP - ionotropic vs. metabotropic receptors - ionotropic: LG receptor; opens when NT/agonist is bound to it - metabotropic: uses ***G proteins*** to activate ***second messengers*** to open and link ion channels across the membrane - do not have ion channels or pass ions through the cell membrane - NEUROTRANSMITTERS: signaling chemical released from the presynaptic neuron that diffuses to alter the functioning of the postsynaptic neuron  - gasotransmitters (gas neurotransmitters) - diffuses out of the neuron as it’s produced (not through vesicle transport) - produced outside of just axon terminals (e.g., dendrites) - diffuses into target cell to trigger ***second messengers*** (not through receptors) - functions: memory formation, hair growth, penile erection, etc. - retrograde transmitters: NT released from postsynaptic cell → presynaptic cell (& alters its functioning) - classic (amine) NTs - ACh: learning, memory, and muscle contraction - DA: motor function and reward - serotonin: behavior (e.g., mood, sleep, sexual behavior, etc.) - NE: sympathetic function; alerting and arousing (i.e., adrenaline) - co-localization: one presynaptic neuron releases & synthesizes more than one NT - DRUGS - drug affinity & efficacy - (binding) affinity: propensity of molecules of a drug (or other ligand) to bind to receptors - efficacy (intrinsic activity): propensity of molecules of a drug (or other ligand) to bind to receptors - (drug) tolerance: with repeated exposure to a drug, an individual becomes less responsive to a constant dose - metabolic: repeated exposure to the drug causes the metabolic machinery of the body to become more efficient at clearing the drug - functional: repeated exposure to the drug causes receptors to be upregulated or downregulated - downregulate: compensatory decrease in receptor availability at the synapses of a neuron - upregulate: compensatory increase in receptor availability at the synapses of a neuron - cross-tolerance: development of tolerance for one drug causes an individual to develop tolerance for another drug - sensitization: body shows an enhanced response to a given drug after repeated doses - presynaptic drug effects 1. effects on transmitter PRODUCTION 2. effects on transmitter RELEASE 3. effects on transmitter CLEARANCE 1. reuptake inhibitors: blocking the presynaptic system that normally reabsorbs transmitter molecules allowing transmitter molecules to stay a bit longer in the synaptic cleft, having a greater effect on the postsynaptic cell - what makes a NT - is produced by neurons and stored in axon terminals - is released when action potentials reach the terminal - is recognized by specific receptors causes changes in the post-synaptic cell - is the primary way that one neuron affects another - neurotransmitters - acetylcholine - sent from: basal forebrain, midbrain - sent to: cortex, amygdala, hippocampus & skeletal muscles, PNS - major roles: learning and memory (CNS) & motor control and parasympathetic activity (PNS) - amino acids - glutamate - sent from: everywhere - sent to: everywhere - major role: most predominant excitatory NT in the brain - GABA - sent from: everywhere - sent to: everywhere - major role: most predominant inhibitory NT in the brain - alcohol: acts on both GABA and glutamate - increases GABA activity; ***agonist*** - decreases glutamate activity; ***antagonist*** - monoamines - dopamine - sent to: midbrain - ventral tegmental area (VTA) - substantia nigra (SN) - sent from: cortex → basal ganglia nucleus accumbens - major roles: reward , learning, motivation, movement - norepinephrine - serotonin - opioid peptides - endorphins - endocannabinoids - tuesday [CamScanner 01-29-2025 11.58.pdf](attachment:ad625722-58aa-4ce3-8560-cb73128d21de:CamScanner_01-29-2025_11.58.pdf) - midbrain: DOPAMINERGIC - VTA (ventral tegmental area): - mesolimbocortical pathway: VTA → nucleus accumbens & cortex - i.e., “reward pathway” - SN (substantia nigra): - mesostriatal pathway: SN → basal ganglia - i.e., Parkinson’s disease (motor sequences) - SEROTONIN (5-HT) - sent from: midbrain & brainstem (raphe nuclei) - sent to: throughout forebrain (aka, everywhere) - major roles: sleep, arousal, mood, answeity, hunger, etc.!!! - many types of 5-HT receptors respond to serotonin - SEROTONERGIC: pathways [CamScanner 01-29-2025 11.47.pdf](attachment:f34ecc79-a780-402c-9ac0-4d0fd3af1568:CamScanner_01-29-2025_11.47.pdf) - midbrain raphe nuclei → forebrain - brainstem raphe nuclei → spinal cord - NOREPINEPHRINE (NE) - sent from: brainstem (locus coeruleus/LC) and midbrain (tegmentum) - sent ot: cortex, thalamus, limbic system - major roles: alertness, mood, sexual behavior - catecholamine production: DA → NE → epinephrine - many drugs target all three NT because DA, NE, and E are chemically similar - E = adrenaline - NE = antagonist of adrenaline - NORADRENERGIC [CamScanner 01-29-2025 11.56.pdf](attachment:6ff2d996-efcd-4767-afae-5038f8e63fc6:CamScanner_01-29-2025_11.56.pdf) - locus coeruleus → forebrain - lateral tegmental area → brainstem and spinal cord --- - PSYCHOACTIVE DRUGS: chemical substance that alters perceptions, mood, and behavior - PRESYNAPTIC EFFECTS - production: - release: - clearance: - POSTSYNAPTIC EFFECTS - receptor: - other cell processes: - wednesday - presynaptic effects: - production: - release: - clearance: - postsynaptic effects: - DRUGS: agonists, inhibitors/stimulants, etc. - alcohol & LSD: both agonists, different effects… which NT, where and how? - alcohol: depressant - GABA: increased - inhibitory - glutamate: decreased - excitatory - LSD: hallucinogen - serotonin: increased - i.e., especially in visual cortex - **recreational drugs** LEGAL - alcohol: glu decreased, GABA increased - caffeine: adenosine decreased - adenosine = NT - nicotine: ACh increased --- MEDICAL - amphetamine: DA increased - oxycodone: endogenous opioids increased - cannabis: endocannabinoids increased [CamScanner 01-29-2025 11.00.pdf](attachment:247fefec-f446-45b4-8350-42488b938e5f:CamScanner_01-29-2025_11.00.pdf) --- ILLEGAL/CONTROLLED SUBSTANCES - cocaine: DA increased - heroin: endogenous opioids increased - LSD: serotonin increased - MDMA: serotonin increased, DA increased - psychiatric medications - antipsychotics: DA decreased - e.g., schizophrenia - antidepressants: serotonin increased, NE increased - e.g., depression, anxiety, PTSD, bipolar - SSRIs decreased reuptake - MAO-Is decreased degradation - anxiolytics: GABA decreased - e.g., anxiety, PTSD - stimulants: dopamine increased, NE increased - e.g., ADHD, narcolepsy - hallucinogens - amphetamines: dopamine (DA) and other NTs agonist - takes dopamine (DA) from inside the cell and “spits” it out - reverse transporters: increases DA release - also block breakdown of DA from synaptic cleft - VERY effective in increasing DA (signaling?) - caffeine: stimulant - blocks adenosine receptors - adenosine = inhibitor (of DA and glutamate_ - DA and glutamate = excitatory - caffeine blocks/inhibits → adenosine (inhibitor) - caffeine increases DA and glutamate activity - friday: quiz - NEUROTRANSMITTERS - glutamate - sent from: everywhere (in the brain) - sent to: everywhere (in the brain) - major roles: excitatory - GABA - sent from: everywhere (in the brain) - sent to: everywhere (in the brain) - major roles: inhibitory - acetylcholine (ACh) - sent from: basal forebrain, midbrain - sent to - CNS: cortex, amygdala, hippocampus - PNS: skeletal muscles, PNS organs - major roles - CNS: learning, memory formation - PNS: motor control, parasympathetic activity - dopamine (DA) - sent from: midbrain - ventral tegmental area (VTA) - substantia nigra (SN) - sent from: cortex → basal ganglia nucleus accumbens - major roles: reward , learning, motivation, movement - serotonin (5-HT) - sent from: midrabin, brainstem (raphe nuclei) - sent to: throughout the brain - major roles: sleep, wakefulness, mood, anxiety, hunger - norepinephrine (NE) - sent from: brainstem, midbrain - sent to: cortex, thalamus, limbic system - major roles: alertness, mood , sexual behavior