Biopsychology: Sensory Systems, Motor Control, and Clinical Neurobiology

Comprehensive vocabulary flashcards covering the anatomical structures, sensory systems, motor pathways, clinical neuropsychiatric disorders, and pharmacology detailed in the lecture transcript.

Anatomy of the Eye

The structural layout of the human eye, including the sclera, cornea, pupil, iris, lens, ciliary body, choroid, retina with its five layered cellular pathway, and the optic nerve.

Anatomy of the Ear

The structural layout of the peripheral auditory and vestibular systems, showing the pinna, lobule, external auditory canal, eardrum, ossicles (malleus, incus, stapes), semicircular canals, cochlea, Eustachian tube, and vestibulocochlear nerve.

Sensations

The detection and intake of raw physical sensory information from the environment.

Perception

How an individual consciously perceives, organizes, and experiences incoming sensory information.

Accommodation

The mechanical ability of the lens of the eye to alter its shape and bend in order to focus light onto the retina.

Presbyopia

A visual condition commonly known as 'old eyes,' characterized by the progressive loss of the lens's elasticity and ability to bend.

Fovea

A concave indentation in the center of the retina containing rods only that corrects for light having to pass through retinal layers twice.

Photopic Vision

Cone-mediated vision ($\text{approximately } 7 \times 10^6$ cones) active in high light settings, providing high visual acuity with a spectral peak around $560\text{ nm}$.

Scotopic Vision

Rod-mediated vision ($\text{approximately } 120 \times 10^6$ rods) active in low light settings, providing high sensitivity with a spectral peak around $460\text{ nm}$.

Purkinje Effect

A shift in visual wavelength and color sensitivity during the transition between illumination levels, where cones are most sensitive to red light and rods are most sensitive to blue light.

Saccades

Rapid, jumping eye movements executed between static points of fixation.

Change Blindness

A visual perceptual limitation where an individual fails to gather information or notice significant changes occurring between visual fixations.

Inattentional Blindness

A failure to consciously see or register visible stimuli when attention is directed elsewhere.

Parvocellular Layers

The top four layers of the thalamus in the retina-geniculate-striate pathway that primarily process visual information transmitted from cones.

Magnocellular Layers

The bottom two layers of the thalamus in the retina-geniculate-striate pathway that primarily process visual information transmitted from rods.

Mach Bands

Non-existent, brain-generated lines perceived at the borders between colors, caused by contrast enhancement.

Lateral Inhibition

A neural mechanism where an excited sensory neuron inhibits adjacent neurons, enhancing the perceived contrast along edges.

Component Theory (Young 1802)

The trichromatic theory proposing that the retina contains distinct receptor cells that mix signals together to create the perception of new colors.

Opponent Processing Theory (Hering 1878)

The color vision theory stating that certain colors are processed in opposing pairs and cannot be perceived simultaneously.

Retinex Theory / Color Constancy (Land 1977)

The theory asserting that an object's perceived color remains constant regardless of variations in the wavelength of the illuminating light source.

Dorsal Pathway

The visual processing stream that projects to the parietal secondary visual cortex to process spatial location ('where').

Ventral Pathway

The visual processing stream that projects to the temporal secondary visual cortex to process object identification and recognition ('what').

Scatoma

A hole or localized blind spot within the visual field.

Prosopagnosia

Face blindness associated with ventral pathway dysfunction, where a person can see individual facial features but cannot label or attach emotional recognition to faces.

Ossicles

The three tiny bones in the middle ear—the malleus, incus, and stapes—that vibrate to mechanically amplify and conduct sound waves to the cochlea.

Organ of Corti

The sensory auditory structure in the cochlea composed of the tectorial membrane on top, the basilar membrane on the bottom, and hair cell receptors that convert mechanical vibrations into electrical signals.

Conduction Deafness

A form of hearing impairment caused by physical damage to the mechanical auditory ossicles of the middle ear.

Nerve Deafness

A sensory hearing impairment resulting from damage to the auditory nerve or the hair cell receptors.

Pacinian Corpuscles

Fast-adapting cutaneous receptors that cease firing shortly after initial contact, conveying information regarding joint location and spatial placement.

Meissner Corpuscles

Rapidly adapting cutaneous mechanoreceptors in the skin that provide high sensitivity to light touch.

Merkel's Disks

Slowly adapting cutaneous receptors that maintain firing after skin indentation to encode information about edges, points, and physical shapes.

Ruffini Endings

Slowly adapting cutaneous mechanoreceptors that fire continuously to signal gradual skin stretch.

Stereognosis

The ability to identify and recognize objects exclusively through the sense of touch.

Dorsal-Column Medial Lemniscus System

The ascending somatosensory pathway that carries touch and proprioceptive information to the brain.

Anterolateral System

The ascending somatosensory pathway that carries pain and temperature information to the brain.

Astereognosia

A somatosensory agnosia characterized by the inability to recognize objects through tactile exploration.

Asomatognosia

A somatosensory agnosia characterized by a lack of knowledge or inability to recognize parts of one's own body.

Anosognosia

The clinical inability of a patient to recognize or understand their own neuropsychological symptoms or brain damage.

Contralateral Neglect

A neurological condition resulting from right parietal lobe damage where a patient is unable to attend to sensory stimuli located on the opposite (left) side of visual space or their own body.

Gate-Control Theory

A model of descending pain control proposing that descending neural signals from the brain can block nociceptive input before pain is perceived.

Periaqueductal Gray (PAG)

A midbrain structure rich in endogenous opiates that plays an essential role in descending pain suppression.

Ageusia

The complete inability to perceive taste.

Anosmia

The complete inability to perceive smell, typically resulting from shearing of olfactory receptor cells.

Actionslip

An unintended, automated motor error that occurs when a habituated motor routine runs inappropriately, such as switching on a light switch upon entering an already lit room.

Apraxia

A disorder characterized by difficulty performing specific voluntary motor movements upon command, commonly linked to damage in the left posterior parietal cortex.

Motor Equivalence

The capacity of the motor system to execute a single task using different muscle effectors or in unpracticed ways (e.g., writing one's name in sand using toes).

Response-Chunking Hypothesis

The motor learning concept stating that practice organizes individual, consciously initiated movements into cohesive chunks of automated, lower-level control.

Reciprocal Innervation

The neural circuitry governing antagonistic muscle pairs that automatically coordinates the contraction of one muscle with the simultaneous relaxation of its antagonist.

Recurrent Collateral Inhibition

A local motor feedback mechanism where a firing motor neuron temporarily self-inhibits via a collateral branch, shifting work to neighboring neurons to allow rest.

Golgi Tendon Organs

Sensory receptors embedded in tendons connecting muscle to bone that detect and transmit information regarding the amount of tension or strain exerted on a muscle.

Muscle Spindles

Sensory receptors embedded in skeletal muscle composed of intrafusal muscle fibers and intrafusal gamma motor neurons that detect and transmit changes in muscle length.

Anhedonia

A negative symptom of schizophrenia and affective disorders characterized by the inability to experience pleasure.

Echolalia

A negative symptom of schizophrenia characterized by the involuntary, parrot-like repetition of words or phrases heard from others.

Tardive Dyskinesia

A severe, permanent motor disorder characterized by involuntary, unconscious facial movements caused by long-term treatment with certain antipsychotics.

Akathisia

An antipsychotic drug-induced motor side effect characterized by extreme subjective restlessness, colloquially termed 'ants in the pants syndrome.'

Phenothiazines

A class of antipsychotic drugs, including chlorpromazine, that bind to D1 and D2 dopamine receptors to effectively treat positive schizophrenic symptoms but not negative symptoms.

Butyrophenones

A class of antipsychotic medications, such as haloperidol and spiroperidol, that target D2-like receptors to effectively treat both positive and negative symptoms of schizophrenia.

Major Depressive Disorder

An affective disorder diagnosed when a patient exhibits at least $5$ symptoms for a minimum of $2$ weeks, requiring the presence of either a depressed mood or suicidal ideation.

Bipolar 1 Disorder

A mood disorder characterized by shifts between depressive episodes and full-blown mania, with mania serving as the primary diagnostic factor.

Bipolar 2 Disorder

A mood disorder characterized by shifts between depressive episodes and hypomania, with depression serving as the primary diagnostic factor.

Cyclothymia

A mild, chronic affective disorder characterized by cyclical mood fluctuations that do not meet the full diagnostic criteria for bipolar disorder.

Monoamine Oxidase Inhibitors (MAOIs)

The earliest class of antidepressant drugs (such as iproniazid) that prevent the enzymatic breakdown of monoamines, requiring strict dietary restrictions against pyricine-containing foods.

Diathesis-Stress Model of Depression

The theoretical framework proposing that depression develops through an interaction between an inherent genetic vulnerability (diathesis) and environmental stressors.

Metabolic (Pharmacokinetic) Tolerance

A form of drug tolerance resulting from the body's peripheral mechanisms (particularly the liver) becoming faster and more efficient at metabolizing and eliminating a drug.

Functional (Pharmacodynamic) Tolerance

A form of drug tolerance occurring within the central nervous system, where neural tissue decreases responsiveness or downregulates receptors to compensate for drug presence.

Conditional Compensatory Responses

Conditioned physiological reactions elicited by drug-associated situational cues that run counter to the drug's effect to maintain bodily homeostasis, producing situational specificity.

Incentive Sensitization Theory

An addiction model asserting that drug relapse is driven by the sensitization of psychological anticipation and the positive incentive value of obtaining the drug.

Buerger's Disease

A severe vascular condition occurring in smokers where blood vessels in the extremities constrict, leading to tissue necrosis, gangrene, and required amputation.

Wernicke-Korsakoff's Syndrome

A dual-stage chronic alcohol disorder consisting of Wernicke's acute confusion and short-term memory deficits along with Korsakoff's long-term retrograde amnesia, primarily driven by thiamine ($\text{vitamin B}_1$) deficiency.

Cannabis Hyperemesis

A chronic adverse condition in heavy marijuana users characterized by persistent nausea, thermoregulatory disruption, and compulsive bathing in hot water.

Cocaine Psychosis

A drug-induced psychotic state produced by high doses of cocaine that closely mimics the positive symptoms of paranoid schizophrenia.