GRE Psych - Biological

Hypothalamus

The brain region governing homeostasis - hunger, thirst, temperature - and the endocrine system.

Sympathetic nervous system

The branch of the autonomic nervous system that triggers fight-or-flight arousal.

Thalamus

The brain’s sensory relay station, routing input (except smell) to the cortex.

Which sense is not routed by the thalamus?

Smell

Norepinephrine

Neurotransmitter for arousal and alertness; drives the fight-or-flight response.

Operant conditioning

Learning in which behavior is shaped by its consequences - reinforcement strengthens it, punishment weakens it.

Medulla

The brainstem structure controlling vital autonomic functions like heartbeat and breathing.

Action potential

The brief electrical impulse traveling down an axon when a neuron fires, following the all-or-none principle.

Wernicke’s area

A temporal lobe region for language comprehension

What is caused by damage to Wernicke’s area?

Fluent (receptive) aphasia

Serotonin

Neurotransmitter regulating mood, sleep, and appetite.

What are low levels of serotonin linked to?

Depression

Amygdala

Brain structure central to fear, aggression, and emotional processing.

Glutamate

The brain’s main excitatory neurotransmitter; central to learning and memory.

Conditioned stimulus

A previously neutral stimulus that, after pairing, triggers a learned response.

Reuptake

The reabsorption of a neurotransmitter by the neuron that released it.

SSRIs block…

serotonin reuptake

Acetylcholine

Neurotransmitter for memory and muscle activation

What is acetylcholine loss associated with?

Alzheimer’s disease

Negative reinforcement

Removing an aversive stimulus to increase/strengthen a behavior.

Positive punishment

Adding an unpleasant stimulus to decrease a behavior.

Temporal lobe

The cortical lobe that processes hearing and is involved in memory and language.

Frontal lobe

The cortical lobe planning judgment, voluntary movement, learning, and personality.

Unconditioned stimulus

A stimulus that naturally and automatically triggers a response.

Cortisol

The body’s primary stress hormone.

What structure releases cortisol?

Adrenal cortex

Classical conditioning

Learning by association; a neutral stimulus paired with one that triggers a reflex comes to evoke the response on its own.

Cerebellum

The brain structure that coordinates voluntary movement and balance.

Endorphins

Endogenous neurotransmitters that reduce pain and produce feelings of pleasure.

Dopamine

Neurotransmitter for reward, motivation, and movement.

Excess activity of dopamine is related to _____, while loss in the substantia nigra causes _______.

Schizophrenia; Parkinsons’s

Resting potential

The negative electrical charge of a neuron at rest (~-70 millivolts).

Parietal lobe

Cortical lobe that processes touch and spatial awareness; receives and interprets signals from other parts of your brain.

Reflex arc

A neural pathway that produces an automatic response without involving the brain.

Antagonist

A drug/molecule that blocks a neurotransmitter’s action.

Corpus callosum

The band of fibers connecting the two cerebral hemispheres, allowing them to communicate.

Synapse

The junction between two neurons where a neurotransmitter crosses from the axon terminal to the next dendrite.

Hippocampus

The brain structure essential for forming new long-term memories.

Occipital lobe

The cortical lobe that processes visual information.

Rods

Retinal photoreceptors for dim-light and peripheral (black-and-white) vision.

Broca’s area

Frontal lobe region for speech production.

What does damage to Broca’s area cause?

Nonfluent (expressive) aphasia

GABA

The brain’s main inhibitory neurotransmitter; calms neural activity and reduces anxiety.

Myelin sheath

The fatty insulation around many axons that speeds the conduction of nerve impulses.

Parasympathetic nervous system

The branch of the autonomic nervous system that calms the body and conserves energy (rest-and-digest).

Positive reinforcement

Adding a pleasant stimulus to increase a behavior.

Cones

Retinal photoreceptors for color vision and fine detail, concentrated in the fovea.

Agonist

Drug/molecule that mimics or boosts the action of a neurotransmitter.

Refractory period

The brief recovery phase after a neuron fires, during which it cannot fire again.

What is the all-or-none principle?

Nerve cells send signals with the same force regardless of the strength impulse causing them to fire.

Basal ganglia

Group of bain structures that help control voluntary muscle movements, executive functions, and process emotions and rewards.

Suprachiasmatic nucleus

Brain structure that regulates most circadian rhythms in the body; biological clock.

Pituitary gland

Brain structure that regulates hormone activity.

Pineal gland

Brain structure that regulates your sleep and wake cycles.

Prosopagnosia

Brain condition where you can't recognize faces or facial expressions.

Long-term potentiation

Cellular mechanism of learning

Weber fraction is _____ no matter the baseline

Constant

What does naloxone block?

Endorphins/opiates

What do benzodiazepines bind?

GABA receptors

Sensation

What happens when our sensory modalities are activated.

Perception

How we understand senses.

What are the three stages of sensation?

Reception (detecting sensory stimuli), transduction (converting sensory inout into electrical neural signals), transmission (sending signals through brain pathways for processing).

Cocktail party phenomenon

Brain involuntarily focuses its attention on something salient; focuses on one voice and blocks others in a loud environment.

Cornea

Protective covering of the eye where light first enters and is focused.

Pupil

The black part in the middle of the eye; acts like the shutter of a camera, and is controlled by the iris.

Iris

The colored disc surrounding the pupil that changes its dilation, allowing more or less light in.

Lens

Focuses on light entering through the pupil (called accommodation), then flips and inverts the image and projects it onto the retina.

Retina

Where the upside-down and inverted image is projected onto and neurons are activated to interpret the image via transduction.

Fovea

The eye’s fixation point, or the part of the eye used when attending to detail; indentation in the retina.

What feature of the eye causes the blind spot?

The optic disc (no photoreceptors).

Lateral geniculate nucleus

The visual part of the thalamus that receives information from the optic nerve.

Optic chiasm

Where visual information gets routed to each side of the brain.

Trichromatic theory

Cones perceive blue, green, and red, and are activated in combination to create a perception of all colors in the visual spectrum.

Opponent-process theory

Retina’s sensory detectors are arranged in color pairs; accounts fo afterimages.

What characteristics of a sound wave determine what we hear?

Amplitude and frequency

Pinna

Flap of skin outside the ear that helps capture and focus sound.

Eardrum

Concentrates sound energy, vibrating when sound from the ear canal hits it.

Ossicles

Three bones in the middle ear connecting the eardrum to the oval window.

Oval window

Compresses fluid in the cochlea and connects the middle ear to the inner ear.

Cochlea

Like a snail’s shell; converts vibrational activity into neural energy.

Organ of Corti

Part in the cochlea that converts sound waves into neural energy.

Gate-control theory

Pain messages are prioritized and the high-priority messages will be delivered first.

Why do certain smells trigger memories?

The nerves of the olfactory bulb connect with the amygdala and hippocampus.

Vestibular sense

Responds to your body’s orientation in space.

Kinesthetic sense

Keeps track of specific body parts and where they are in space, using receptors in joints and muscles.

Absolute threshold

The smallest stimulus consciously perceptible at least 50% of the times encountered.

Difference threshold/just-noticeable difference

The amount a stimulus needs to change before the change can be detected; for hearing, the change must be 5%.

Weber-Fechner law

The amount of stimulus change needed to perceive a difference is proportional to the intensity of the existing stimulus.

Signal detection theory

Acknowledges the motivation to perceive a certain stimulus.

Top-down processing

Uses information we already have in our brains to fill in gaps in the things we sense.

Bottom-up processing

Building a perception of an object by mentally compiling all of its features.

What are the four Gestalt rules of perception?

Proximity, continuity, similarity, and closure

What three types of constancy allow us to recognize an item despite the changes in how we see it?

Size constancy, shape constancy, and brightness/color constancy.

__________ ____ are used to perceive depth, and require use of both eyes, while __________ ____ only require use of one eye.

Binocular cues; monocular cues

How would Gestalt psychologists explain perception?

Perception is a result of top-down processing, since the way people explain the world is by creating a system of organization.

How would structuralists explain perception?

Structuralists would argue that perception is a result of bottom-up processing, meaning it begins with sensory input and builds up to form a complete perceptual experience.

Phi phenomenon

We attribute apparent motion to a series of still images that differ slightly from one another.

Terminal threshold

The upper limit of perceivable stimuli.

Basilar membrane

Vibrates in response to sound coming from the stapes.

Two-point threshold

The point at which touch from two separate objects is recognized.