Psychology Units 3 & 4: Brain Function, Sensation, Memory, Learning, and Social Influences

Comprehensive vocabulary flashcards covering brain structures, neurotransmitters, sensory processing, memory architecture, conditioning and learning paradigms, and social psychology concepts.

Amygdala

An almond-shaped structure located in the medial temporal lobe of the brain that is central to emotion, aggression, and implicit learning, and vital in initiating and processing emotional responses and forming emotional memories.

Autonomic nervous system (ANS)

A division of the peripheral nervous system responsible for communication between the central nervous system and non-skeletal (visceral) and involuntary (cardiac) muscles, internal organs, and glands that carry out bodily functions.

Basal ganglia

A group of structures in the brain—including the caudate nucleus, putamen, globus pallidus, and subthalamic nucleus—involved in the control, initiation, and regulation of voluntary movement by gathering and channelling information to the motor cortex.

Broca's area

A region in the association area of the left frontal lobe that acts as the speech production centre of the brain, coordinating the movement of the lips, tongue, vocal cords, and the articulation of words.

Central nervous system (CNS)

The major division of the nervous system comprising the brain and the spinal cord; it processes and responds to sensory input received from the peripheral nervous system.

Cerebellum

A hindbrain structure responsible for coordinating and remembering smooth, well-sequenced voluntary movements, regulating motor balance, and supporting implicit procedural memory.

Cerebral cortex

The multilayered outer surface of the cerebrum responsible for receiving environmental information, controlling responses, and enabling complex voluntary movements and higher-order thinking processes.

Cerebrum

The part of the forebrain divided into two hemispheres that is most responsible for voluntary movement and complex thought processes such as perception, imagination, judgement, and decision-making.

Corpus callosum

The thick band of about $200\text{ million}$ nerve fibres connecting the left and right cerebral hemispheres of the brain.

Frontal lobe

The largest lobe of the cerebral cortex, responsible for initiating voluntary movement, speech production, abstract thought, planning, judgement, problem-solving, and aspects of personality and emotion.

Parietal lobe

The cerebral lobe containing the primary somatosensory cortex that processes sensations such as touch, pressure, temperature, and pain, and enables awareness of one's body and surrounding spatial orientation.

Occipital lobe

The cerebral cortex located at the rear of the brain containing the primary visual cortex and association areas responsible for receiving and integrating visual stimuli.

Temporal lobe

The cerebral lobe situated at the side of the head above the ears that contains the primary auditory cortex and Wernicke's area, responsible for hearing, language comprehension, and object recognition.

Geschwind's territory

An area in the inferior parietal lobe connected to Broca's and Wernicke's areas whose multimodal neurons simultaneously process auditory and visual properties of words to comprehend their meaning.

Hippocampus

A finger-sized curved structure located in the medial temporal lobe essential for the consolidation of explicit (declarative) memories and the formation and storage of spatial navigation memories.

Homeostasis

A self-regulating biological process by which the body maintains a stable, balanced internal environment while adjusting to changing conditions.

HPA axis

A major neuroendocrine system comprising the hypothalamus, pituitary gland, and adrenal gland that interacts through a feedback loop to regulate digestion, immunity, mood, emotions, and physiological stress responses.

Hypothalamus

A forebrain structure that regulates homeostasis, controls the autonomic nervous system, and manages basic survival behaviours including eating, drinking, sleeping, and reproductive activity.

Limbic system

A collection of interconnected brain structures—including the amygdala, hypothalamus, thalamus, and midbrain areas—involved in emotion, memory, motivation, and basic survival behaviour.

LeDoux's model of emotion

A theoretical model proposing that emotional stimuli are processed via two pathways: a fast 'short route' directly from the thalamus to the amygdala, and a slower 'long route' routed via the sensory cortex and hippocampus to the amygdala.

Monosynaptic reflex arc

A neural pathway involving only two neurons (one sensory neuron and one motor neuron) and a single synapse in the spinal cord, responsible for rapid involuntary responses such as the patellar reflex.

Polysynaptic reflex arc

A spinal reflex pathway comprising three or more neurons (sensory, motor, and one or more spinal interneurons) containing multiple synapses.

Motor neurons

Efferent neurons that transmit motor commands from the central nervous system to effector muscles or glands to initiate movement or support bodily secretions.

Sensory neurons

Afferent neurons that detect sensory stimuli via external or internal receptors and convey nerve impulses into the central nervous system.

Parasympathetic nervous system

The branch of the autonomic nervous system responsible for maintaining routine day-to-day bodily functioning, promoting digestion, and calming the body to restore homeostasis following sympathetic arousal.

Sympathetic nervous system

The branch of the autonomic nervous system that mobilises bodily resources for immediate physical action during times of threat, stress, or high emotional arousal, activating the fight-flight-freeze response.

Somatic nervous system

The division of the peripheral nervous system composed of sensory neurons conveying afferent signals to the CNS and motor neurons delivering efferent commands to control voluntary skeletal muscle movements.

Primary motor cortex

The cortical band situated at the rear of each frontal lobe that executes voluntary movement of skeletal muscles through contralateral organisation.

Primary somatosensory cortex

The region at the front of each parietal lobe that receives and processes bodily sensations such as touch, temperature, pressure, and pain from the opposite side of the body.

Wernicke's area

A region situated in the left temporal lobe responsible for the comprehension of speech and the formulation of coherent, grammatically correct sentences.

Action potential

A rapid, momentary reversal in the electrical membrane potential of a neuron (from $-70\,mV$ to $+40\,mV$) that propagates along the axon to trigger neurotransmitter release.

Dendrites

Branch-like extensions of a neuron that receive chemical signals across synapses from neighbouring neurons or sensory receptors and convey them toward the cell body.

Axon

The elongated fibre of a neuron along which electrical nerve impulses are propagated away from the soma toward the terminal buttons.

Myelin

A white, fatty substance that coats and insulates certain axons, preventing electrical interference and accelerating the speed of nerve impulse transmission.

Lock and key process

The mechanism of synaptic transmission wherein uniquely shaped neurotransmitter molecules (the 'key') bind specifically to complementary receptor proteins (the 'lock') on the postsynaptic membrane.

Glutamate

The primary excitatory neurotransmitter in the central nervous system, vital for neuroplasticity, memory, and learning by increasing the likelihood of postsynaptic action potentials.

GABA (gamma-aminobutyric acid)

The chief inhibitory neurotransmitter in the brain, responsible for counteracting excitation, regulating arousal, and preventing severe anxiety disorders.

Acetylcholine

A neurotransmitter in the brain, spinal cord, and PNS that stimulates muscle contractions, supports autonomic functions, and facilitates learning, memory, and REM sleep.

Dopamine

A neurotransmitter involved in motor control, motivation, reward pathways, pleasure centres, and voluntary movement coordination.

Serotonin

A neurotransmitter that regulates mood, sleep-wake cycles, emotional wellbeing, appetite, bowel movements, and inhibits aggressive behaviours.

Substantia nigra

A midbrain nucleus within the basal ganglia containing dopamine-producing neurons whose degeneration is the hallmark of Parkinson's disease.

Parkinson's disease

A progressive neurodegenerative condition caused by the degeneration of dopamine-releasing neurons in the substantia nigra, resulting in tremors, rigidity, bradykinesia, and postural instability.

Alzheimer's disease

A progressive neurodegenerative disorder characterised by severe declarative memory loss, confusion, and cognitive decline, associated with depleted acetylcholine, amyloid plaques, and neurofibrillary tangles.

Amyloid plaques

Dense, abnormal protein deposits that accumulate between neurons in Alzheimer's disease patients, disrupting cellular communication and contributing to neural death.

Absolute threshold

The minimum intensity of physical energy needed for a sensory receptor system to detect a stimulus at least $50\%$ of the time.

Transduction

The biological process wherein sensory receptors convert environmental physical stimuli into electrochemical signals (nerve impulses) suitable for central processing.

Transmission

The movement of electrochemical nerve impulses from sensory receptor structures along sensory pathways to the brain for processing.

Perception

The active cognitive process by which the brain selects, organises, and interprets incoming sensory information to create meaningful experiences.

Rods

Photoreceptors concentrated in the peripheral retina specialised for vision in low-light conditions, detecting motion and producing low-acuity, achromatic images.

Cones

Photoreceptors densely packed in the fovea that operate in bright illumination to produce high visual acuity and colour vision.

Receptive field

The specific region of sensory space in which the presentation of a stimulus alters the firing activity of a particular sensory ganglion cell or cortical neuron.

Optic chiasm

The anatomical junction where nerve fibres from the nasal halves of each retina cross to the opposite cerebral hemisphere, ensuring contralateral visual processing.

Cochlea

The fluid-filled, coiled structure of the inner ear containing the basilar membrane and auditory hair cells responsible for auditory transduction.

Place theory

An auditory theory proposing that pitch perception depends on the specific physical location of maximum vibration along the basilar membrane, explaining high-frequency sound perception.

Frequency theory

An auditory theory proposing that pitch is perceived by the rate of vibration of the entire basilar membrane, which matches the firing frequency of auditory nerve impulses for lower frequencies.

Timbre

The unique quality, color, or character of a sound wave that allows a listener to distinguish between different instruments or voices of identical pitch and loudness.

Bottom-up processing

Stimulus-driven sensory processing that constructs a holistic perception by combining raw, detailed sensory inputs without prior expectations.

Top-down processing

Conceptually driven processing wherein prior knowledge, memories, context, and expectations influence the interpretation of incoming sensory inputs.

Perceptual set

A cognitive predisposition or mental framework to interpret incoming sensory stimuli in a particular manner based on past experience, context, motivation, or emotional state.

Figure-ground organisation

A primary Gestalt perceptual principle wherein a visual scene is organised into a prominent, bounded central figure separated from a background.

Closure

A Gestalt organising principle describing the psychological tendency to mentally fill in gaps or missing contours of an incomplete visual figure to perceive a whole form.

Retinal disparity

A binocular depth cue arising from the horizontal separation of the eyes ($6\text{ to }7\,cm$), providing slightly divergent retinal images that the brain compares to gauge depth.

Convergence

A binocular depth cue where ciliary and ocular muscles turn the eyes inward to maintain focus on an approaching object within approximately $7\,m$.

Accommodation

A monocular depth cue wherein ciliary muscles adjust the curvature of the crystalline lens to focus images of near or distant objects sharply onto the retina.

Linear perspective

A monocular pictorial depth cue where apparent parallel lines converge toward a vanishing point as they recede into the distance.

Interposition

A monocular depth cue that occurs when one object partially obscures or overlaps the view of another, causing the partially obscured object to be perceived as farther away.

Texture gradient

A pictorial depth cue where fine surface detail and distinct texture gradually become denser, smoother, and less defined as distance increases.

Müller-Lyer illusion

A geometric visual illusion where two lines of identical length appear unequal due to inward-pointing versus outward-pointing arrowheads, influenced by depth judgements and carpentered-world exposure.

Multi-store model of memory

Atkinson and Shiffrin's structural memory model positing that memory consists of three separate, interacting stores: sensory memory, short-term memory, and long-term memory.

Iconic memory

The visual sensory register that briefly preserves visual images in their raw form for approximately $0.3\text{ to }0.4\text{ seconds}$.

Echoic memory

The auditory sensory register that retains raw sound representations for approximately $3\text{ to }4\text{ seconds}$ to allow speech comprehension.

Chunking

The mnemonic coding technique of organising individual bits of information into larger, meaningful cohesive units to increase effective short-term memory capacity.

Maintenance rehearsal

The repetitive cycling of information in conscious awareness to maintain it actively within short-term memory without altering its semantic meaning.

Elaborative rehearsal

The process of linking new information meaningfully to pre-existing knowledge stored in semantic networks to facilitate consolidation into long-term memory.

Working memory model

Baddeley and Hitch's multi-component model describing active short-term mental manipulation through a central executive, phonological loop, visuospatial sketchpad, and episodic buffer.

Central executive

The supervisory component of working memory that directs attention, filters irrelevant distractions, coordinates slave systems, and links to long-term memory.

Phonological loop

The slave component of working memory that processes and temporarily holds auditory information via a phonological store ('inner ear') and an articulatory loop ('inner voice').

Visuospatial sketchpad

The slave component of working memory responsible for temporarily storing and manipulating visual imagery and spatial coordinates.

Episodic buffer

A limited-capacity component of working memory that integrates multi-modal information from slave systems and long-term memory into chronological, coherent episodes.

Levels of processing (LOP) model

Craik and Lockhart's memory framework proposing that memory durability is determined by depth of mental encoding: shallow structural, moderate phonemic, or deep semantic processing.

Explicit memory

Declarative long-term memory requiring conscious, intentional recollection of factual information, personal experiences, and concepts.

Implicit memory

Non-declarative long-term memory operating outside conscious awareness, encompassing procedural motor skills, priming effects, and classically conditioned responses.

Episodic memory

A subtype of explicit memory consisting of personally experienced events situated within specific spatial and temporal contexts.

Semantic memory

A subtype of explicit memory storing generalised, impersonal factual knowledge, concepts, rules, and language independent of acquisition context.

Semantic networks

Hierarchical models of long-term memory organization where concepts (nodes) are interrelated through meaningful semantic associations.

Free recall

A retrieval method in which participants reproduce previously learned items in any sequence without the assistance of prompts or cues.

Cued recall

A retrieval method where specific prompts, hints, or associations are provided to guide access to stored target information.

Recognition

A measure of memory retrieval requiring the identification of previously learned information from among a presented array of distractors.

Relearning

The most sensitive retention measure, demonstrating residual learning by tracking the time or trials saved when acquiring previously learned but forgotten information.

Encoding specificity principle

Tulving's principle asserting that memory retrieval is most successful when retrieval cues closely mirror the internal and external conditions present during original encoding.

Context-dependent cues

Environmental stimuli present in the external setting during encoding (such as smells, sounds, or visual surroundings) that serve as prompts for retrieval.

State-dependent cues

Internal physiological or psychological states (such as mood, anxiety level, or sobriety) present during encoding that facilitate retrieval when reinstated.

Proactive interference

The forgetting phenomenon where previously consolidated memories disrupt the acquisition, encoding, or retrieval of newly learned information.

Retroactive interference

The forgetting phenomenon where recently learned new information interferes with the retrieval of previously learned material.

Method of loci

A mnemonic visualization technique where items to be memorized are mentally deposited in distinct landmarks along an imagined familiar spatial route.

Spacing effect

The memory phenomenon whereby distributed practice spread across spaced intervals produces more durable consolidation and retention than massed practice.

Interleaving

A study practice involving the alternation of multiple related topics or skill sets within a single session, promoting comparative categorization and retrieval.

Classical conditioning

A passive learning process wherein an organism forms a reflexive association between an unconditioned stimulus and a neutral stimulus, converting the neutral stimulus into a conditioned stimulus.

Extinction (classical conditioning)

The progressive diminishment and eventual cessation of a conditioned response when the conditioned stimulus is repeatedly presented without the unconditioned stimulus.

Spontaneous recovery

The reappearance of an extinguished conditioned response following a rest period, without any intervening pairings with the unconditioned stimulus.