Introductory Psychology: Neuroscience, Sensation & Perception, and Memory

Comprehensive practice flashcards reviewing all key vocabulary across biological psychology, neuronal communication, brain anatomy, sensory systems, perceptual organization, and memory mechanisms.

Natural Selection

The evolutionary process based on Charles Darwin's theory in which organisms with small, inherited variations that increase their ability to compete, survive, and reproduce pass on these traits, resulting in greater reproductive success.

Encephalization

The evolutionary increase in human brain size over time.

Bipedalism

The evolutionary adaptation and ability to walk upright on two feet.

Chromosomes

Thread-like strands of DNA found in the cell nucleus that carry genes and genetic messages from biological parents (humans have 46 chromosomes, or 23 pairs per parent).

Gene

A functional unit of hereditary material carried on chromosomes that provides the chemical 'recipe' for protein synthesis.

Genome

An organism's total, complete set of genetic material or nuclear DNA.

Epigenetics

The study of heritable changes in gene function and expression that occur without an alteration in the underlying DNA sequence.

Genotype vs. Phenotype

Genotype refers to the specific genetic makeup or set of genes an organism carries, whereas phenotype refers to observable physical and behavioral traits.

Lesion

An area of damaged brain tissue, which can be created experimentally in animal research to examine behavioral consequences.

Electroencephalogram (EEG)

A brain monitoring technique using scalp electrodes that measures electrical activity, providing rapid temporal resolution to study sleep, dreaming, and cognitive tasks.

Computed Tomography (CT)

A structural brain imaging method that combines multiple X-ray measurements to construct a three-dimensional image of brain anatomy.

Magnetic Resonance Imaging (MRI)

A structural imaging technique that uses magnetic fields to measure energy released by water molecules in biological tissues, producing detailed images of soft tissues and tumors.

Positron Emission Tomography (PET)

A functional brain imaging scan that measures metabolic activity by injecting radioactive glucose molecules and tracking where glucose is utilized most.

Functional Magnetic Resonance Imaging (fMRI)

A standard functional brain imaging technique that visualizes brain activity by tracking changes in blood oxygen levels (BOLD response).

Magnetoencephalography (MEG)

A brain imaging technique that detects and measures the tiny magnetic fields generated by the electrical activity of neurons, combining high spatial and temporal speed.

Transcranial Magnetic Stimulation (TMS)

A non-invasive method applying strong, rapidly changing magnetic fields to the scalp to temporarily enhance or disrupt regional brain activity, helping establish causal relationships.

Deep Brain Stimulation (DBS)

A surgical technique where electrodes are implanted directly into specific brain regions to deliver electrical stimulation and map cortical areas.

Default Mode Network

An interconnected network of brain structures that remains active when an individual is in a resting, non-task-focused state.

Neuro-seduction

The uncritical tendency to place disproportionate confidence in neuroscientific explanations or brain scan imagery.

Localization of Function

The research principle of identifying specific brain areas active during distinct psychological and cognitive tasks.

Neuron

A specialized cell in the nervous system that processes and transmits information using chemical and electrical signals; approximately 86 billion exist in the human brain.

Dendrites

Branch-like extensions of a neuron that receive chemical signals from adjacent cells.

Axon Hillock

The specialized region connecting the cell body to the axon where electrical nerve impulses (action potentials) are generated.

Myelin Sheath

A fatty insulating layer wrapping around axons that dramatically increases the speed and efficiency of electrical signal transmission.

Nodes of Ranvier

Gaps along the myelin sheath of an axon that allow for ion exchange and facilitate rapid signal propagation.

Astrocytes

Star-shaped glial cells that facilitate neuronal communication, regulate blood flow, and contribute to the structural integrity of the blood-brain barrier.

Oligodendrocytes

Glial cells that produce and maintain myelin sheaths around neuronal axons in the central nervous system.

Multiple Sclerosis (MS)

An autoimmune disorder in which the immune system degrades the myelin sheath, causing slowed neural transmission and motor coordination deficits.

Blood-Brain Barrier

A selective semipermeable membrane that shields the brain from foreign substances, harmful bacteria, and large circulating toxins.

Resting Potential

The electrical charge across a neuron's membrane when inactive, characterized by a negative interior typically measured around $-60\,\text{mV}$.

Threshold of Excitation

The critical level of electrical depolarization required to open voltage-gated ion channels and trigger an action potential (e.g., roughly $-65\,\text{mV}$).

Action Potential

A rapid, transient electrical impulse that travels along the axon, initiated by an influx of positive ions followed by an outflow of positive ions.

All-or-None Law

The principle that an action potential is either fired at full strength once threshold is reached or not fired at all, with no variation in size based on stimulus intensity.

Absolute Refractory Period

A brief period immediately following an action potential during which a neuron is completely unable to initiate another action potential.

Reuptake

The process by which released neurotransmitter molecules are reabsorbed back into the axon terminal of the presynaptic sending neuron for recycling.

Glutamate

The central nervous system's primary excitatory neurotransmitter, crucial for learning, memory, and increasing neuronal firing.

GABA (Gamma-Aminobutyric Acid)

The primary inhibitory neurotransmitter in the brain that suppresses neural activity and functions like the nervous system's braking mechanism.

Acetylcholine

A neurotransmitter that triggers muscle contraction at motor junctions and plays vital roles in selective attention, arousal, and memory.

Dopamine

A monoamine neurotransmitter strongly associated with motor function, reward processing, motivation, and goal anticipation.

Norepinephrine

A monoamine neurotransmitter responsible for sustaining arousal, alertness, conscious attention, and emotional mood states.

Serotonin

A monoamine neurotransmitter involved in regulating mood, sleep-wake cycles, appetite, aggression, and internal temperature.

Endorphins

A specialized class of neuropeptides that act as endogenous pain relievers and enhance sensations of pleasure.

Anandamide

A neurotransmitter that binds to cannabinoid receptors and regulates eating behavior, motivation, memory consolidation, and sleep.

Agonist vs. Antagonist

An agonist is a psychoactive substance that enhances or mimics neurotransmitter activity at receptor sites, whereas an antagonist binds to receptor sites and diminishes or blocks their effects.

Neural Plasticity

The capacity of the nervous system to modify its structural organization and functional connections over time in response to learning, experience, or injury.

Synaptogenesis

The developmental process involving the formation of new synaptic junctions between communicating neurons.

Pruning

The systematic removal and retraction of unneeded neurons and non-functional synaptic connections during neurodevelopment.

Neurogenesis

The creation of new functional neurons from neural stem cells in the brain, occurring both in utero and continuing in select regions throughout adulthood.

Meninges

The three protective membranes encasing the brain and spinal cord: the dura mater, arachnoid membrane, and pia mater.

Cerebrospinal Fluid (CSF)

A clear fluid circulating through the brain ventricles and spinal cord that cushions the central nervous system against injury and supplies essential nutrients.

Corpus Callosum

A thick band of nerve fibers connecting the left and right cerebral hemispheres that facilitates interhemispheric communication.

Frontal Lobes

Cerebral lobes responsible for voluntary motor control, decision-making, executive functions, impulse regulation, and speech production.

Prefrontal Cortex

The anterior cortical zone of the frontal lobes in charge of high-level cognitive processes, forward planning, self-awareness, and personality expression.

Homunculus

A neurological 'map' representing the relative proportion of motor or somatosensory cortex dedicated to controlling and sensing various human body parts.

Broca's Area

A specialized region situated within the left frontal lobe essential for the physical generation and coordination of fluent speech.

Central Sulcus

A prominent anatomical groove on the cerebral surface that separates the frontal lobe from the parietal lobe.

Parietal Lobes

Cortical regions containing the primary somatosensory cortex that process tactile information, temperature, pain, and spatial orientation.

Unilateral Neglect

A neurological condition typically caused by damage to the parietal lobe where a patient completely overlooks or ignores the opposite side of space.

Temporal Lobes

Lateral cerebral regions containing the auditory cortex and Wernicke's area, essential for auditory processing, language comprehension, and autobiographical memory storage.

Wernicke's Area

A region in the left temporal lobe specialized for the processing and comprehension of spoken and written language.

Fusiform Face Area (FFA)

A specialized cortical subregion within the temporal lobe dedicated to recognizing human faces and highly practiced visual configurations.

Occipital Lobe

The posterior lobe of the cerebral cortex dedicated entirely to visual processing and primary visual reception.

Frontotemporal Dementia

A neurodegenerative condition targeting the frontal and temporal lobes that results in progressive personality disintegration, loss of social inhibition, and impaired judgment.

Basal Ganglia

Subcortical nuclei deep within the cerebral hemispheres that select and initiate voluntary movements; impaired in Parkinson's disease and Tourette's disorder.

Thalamus

The primary sensory relay hub in the brain that filters and transmits incoming sensory data (except olfaction) directly to primary sensory cortices.

Hypothalamus

A limbic system structure that preserves internal bodily homeostasis by regulating hunger, thirst, sexual drives, temperature, and direct control over the pituitary gland.

Amygdala

An almond-shaped limbic structure critical for processing primary emotions, threat detection, fear conditioning, and emotional memory consolidation.

Hippocampus

A temporal-lobe limbic structure indispensable for spatial navigation and the consolidation of short-term memories into explicit, long-term conscious storage.

Cerebellum

The 'little brain' situated at the posterior base of the skull, responsible for maintaining posture, equilibrium, motor coordination, and learned motor skills.

Brain Stem

The basal region of the brain consisting of the midbrain, pons, and medulla, acting as a relay highway and regulating fundamental autonomic life functions.

Reticular Activating System (RAS)

A network of pathways within the brain stem that projects to the cerebral cortex to modulate alertness, physiological arousal, and sleep-wake transitions.

Pons

A structure of the hindbrain that serves as a bridge relaying signals between the cerebral cortex and cerebellum, also playing a role in dreaming.

Medulla

The base of the brain stem directly controlling vital autonomic reflexes including respiration, heart rate, and blood pressure.

Somatic Nervous System

The PNS subdivision consisting of sensory and motor nerves that monitors external sensory signals and executes voluntary movements of skeletal muscles.

Autonomic Nervous System

The PNS division governing involuntary activities of internal organs and glands, subdivided into sympathetic and parasympathetic branches.

Sympathetic vs. Parasympathetic Nervous System

The sympathetic system mobilizes physiological energy during stress and emergencies ('fight or flight'), whereas the parasympathetic system conserves energy and restores baseline homeostasis ('rest and digest').

Endocrine System

A regulatory communication network of ductless glands that secrete hormones directly into the bloodstream to modulate physiological development and behavioral states.

Pituitary Gland

The 'master gland' controlled by the hypothalamus that regulates growth, fluid retention in kidneys, and secretes hormones such as oxytocin.

Oxytocin

A pituitary hormone involved in reproductive functions, uterine contractions in childbirth, lactation, social attachment, and interpersonal trust.

Adrenal Glands

Glands located atop the kidneys that secrete adrenaline (epinephrine) for acute emergency energy and cortisol for chronic stress and metabolic regulation.

Psychophysics

The scientific discipline studying the quantitative relationship between the physical properties of external stimuli and our psychological sensory experiences.

Absolute Threshold

The lowest boundary of stimulus intensity that can be consciously detected by our sensory receptors at least $50\%$ of the time.

Signal Detection Theory

A framework evaluating perceptual judgment under conditions of sensory uncertainty, categorizing responses into hits, misses (false negatives), false alarms (false positives), and correct rejections (true negatives).

Sensory Adaptation

The gradual decline in sensory receptor responsiveness following sustained, unchanging stimulation.

Cross-Modal Processing

The perceptual integration of inputs from multiple sensory channels simultaneously, exemplified by phenomena such as synesthesia and the McGurk effect.

Visible Spectrum

The narrow range of electromagnetic wavelengths that human photoreceptors can detect, spanning approximately $400\,\text{nm}$ (violet/blue) to $700\,\text{nm}$ (orange/red).

Cornea and Lens

The cornea is the transparent outer layer focusing light into the eye; the lens changes its curvature to adjust optical focus directly onto the retina.

Rods and Cones

Rods are photoreceptors enabling vision in low-light conditions; cones provide sharp visual acuity and color vision in well-lit conditions and are concentrated in the fovea.

Myopia vs. Hyperopia

Myopia (nearsightedness) occurs when light focuses in front of the retina due to a steep cornea or elongated eyeball; hyperopia (farsightedness) occurs when light focuses behind the retina due to a flat cornea or shortened eyeball.

Trichromatic Theory

The theory proposing that color vision emerges from differential stimulation of three separate cone types tuned to primary wavelengths: blue, green, and red.

Opponent Process Theory

The theory stating that color perception is organized into mutually inhibitory complementary pairs: red versus green, and blue versus yellow.

Frequency and Pitch

Frequency is the number of sound wave cycles per second measured in Hertz ($\text{Hz}$), which directly determines the perceived pitch of a sound.

Ossicles

The three tiny bones in the middle ear—the hammer (malleus), anvil (incus), and stirrup (stapes)—that mechanically amplify sound vibrations from the eardrum to the inner ear.

Cochlea

A fluid-filled, snail-shaped inner ear structure where hair cells along the basilar membrane and organ of Corti transduce mechanical sound vibrations into action potentials.

Vestibular Sense

The sensory system operating through three fluid-filled semicircular canals in the inner ear that detects head position, motion, and sustains bodily equilibrium.

Proprioception (Kinesthesis)

The body's internal sense of muscle position, limb movement, and spatial orientation without requiring visual feedback.

Nociceptors

Free nerve ending sensory receptors that respond to actual or potential tissue damage and transmit pain signals to the central nervous system.

Olfactory and Gustatory Convergence

The neurosensory process wherein chemical signals from airborne odors (olfaction) and tastants on tongue papillae (gustation) merge within the orbitofrontal cortex to create unified flavor perceptions.

Bottom-Up vs. Top-Down Processing

Bottom-up (data-driven) processing constructs perceptions strictly from raw sensory cues, whereas top-down (concept-driven) processing relies on prior knowledge, context, and expectations to interpret incoming stimuli.

Retinal Disparity

A binocular depth cue resulting from the slightly distinct angles each eye has of the same object, allowing the brain to compute relative depth and distance.