Comprehensive Psychology Review: History, Neuroscience, Sensation, Perception, and Consciousness

Comprehensive vocabulary flashcards covering the origins of experimental psychology, neuroanatomy, neural signaling, sensation, visual and auditory perception, models of attention, and states of consciousness.

Mentalism

The philosophical perspective originating with Aristotle proposing that the psyche (the nonmaterial mind) is the ultimate source of all human behavior, including thought, reasoning, and memory.

Dualism

René Descartes' philosophical position asserting that a nonmaterial mind governs advanced cognitive functions, while the physical brain directs basic mechanical behaviors.

Chronoscope

A precision mechanical measurement tool utilized in early experimental psychology laboratories to accurately measure reaction time and the speed of mental processes.

Psychophysics

An experimental discipline developed by scientists such as Ernst Weber and Gustav Fechner that quantifies the relationship between physical stimuli and subjective psychological sensations.

Absolute Threshold

The minimum intensity of physical stimulation required for a stimulus to be detected $50\%$ of the time.

Difference Threshold (Just Noticeable Difference)

The minimum amount of change in physical stimulation necessary for an observer to detect a difference between two stimuli.

Weber's Law

A psychophysical principle stating that the just noticeable difference between two stimuli is a constant proportion of the original stimulus intensity rather than a constant amount.

Structuralism

An early school of psychology founded by Edward Titchener seeking to identify the fundamental elements of conscious experience—sensations, images, and feelings—through systematic introspection.

Introspection

The systematic examination and subjective reporting by trained observers of their own immediate conscious thoughts, feelings, and perceptual sensations in response to controlled stimuli.

Functionalism

A school of thought championed by William James emphasizing the adaptive purpose and utility of conscious mental processes in real-world environments, heavily influenced by Darwinian evolutionary theory.

Central Nervous System (CNS)

The division of the nervous system composed of the brain, encased within the protective skull, and the spinal cord, encased within the vertebrae.

Autonomic Nervous System

The branch of the peripheral nervous system that regulates internal bodily activities, organs, and glands; divided into the sympathetic (arousing) and parasympathetic (calming) divisions.

Phrenology

An early 19th-century theory developed by Franz Gall postulating that specific psychological faculties and personality traits are localized in distinct brain areas and reflected by bumps on the skull.

Frontal Lobe

The anterior cerebral cortical lobe responsible for higher-order cognitive functions including planning, organizing, impulse control, and motor execution.

Temporal Lobe

The lateral cortical lobe primarily involved in auditory processing, language comprehension, memory formation, taste, and smell.

Parietal Lobe

The cerebral cortical lobe situated behind the frontal lobe that processes somatosensory information (touch) and mediates spatial awareness.

Occipital Lobe

The posterior region of the cerebral cortex dedicated entirely to receiving and processing visual information.

Corpus Callosum

A dense band of transverse white matter fibers that connects the left and right cerebral hemispheres, enabling interhemispheric communication.

Meninges

A triple-layered protective membrane encasing the central nervous system, consisting of the dura mater, arachnoid membrane (containing CSF in the subarachnoid space), and pia mater.

Functional Magnetic Resonance Imaging (fMRI)

A functional neuroimaging method that tracks blood oxygenation level-dependent (BOLD) changes in real time while subjects execute cognitive tasks to map brain activity.

Diffusion Tensor Imaging (DTI)

A static magnetic resonance imaging technique that detects the directional diffusion of water molecules along axons to visualize and map white matter tracts in the brain.

Deep-Brain Stimulation (DBS)

A surgical procedure involving the implantation of electrodes deep within subcortical brain structures to deliver low-voltage electrical current to treat motor disorders like Parkinson's disease.

Reticular Formation

A network of nuclei located throughout the brainstem that plays a critical role in regulating sleep, alertness, and physiological arousal.

Thalamus

A bilateral subcortical structure serving as the sensory gateway of the brain, routing sensory signals to appropriate regions of the cerebral cortex.

Hypothalamus

A crucial subcortical structure located below the thalamus that regulates fundamental physiological functions, hormone release, and body homeostasis.

Hippocampus

A limbic system structure in the temporal lobe essential for the formation and consolidation of long-term memories.

Amygdala

An almond-shaped limbic structure situated adjacent to the hippocampus that regulates emotional processing, particularly fear and threat responses.

Astrocyte

A star-shaped glial cell providing physical support to neurons, transferring nutrients, and contributing to the blood-brain barrier via specialized end feet surrounding cerebral blood vessels.

Oligodendrocyte

A specialized type of glial cell responsible for producing the insulating myelin sheath surrounding neuronal axons within the central nervous system.

Schwann Cell

A glial cell in the peripheral nervous system that wraps around single axonal segments to form the protective and insulating myelin sheath.

Action Potential

A rapid, all-or-none electrical impulse that travels down the axon of a neuron to transmit signals across long distances and facilitate synaptic communication.

Agonist

A psychoactive chemical or substance that binds to receptors or acts at the synapse to enhance or mimic the normal function of a neurotransmitter.

Antagonist

A chemical substance that binds to a neurotransmitter receptor site or acts synaptically to block, inhibit, or diminish neurotransmitter action.

Dopamine

A major monoamine neurotransmitter strongly associated with two primary brain pathways: motor control (degenerating in Parkinson's disease) and reward/motivation signaling.

Transduction

The fundamental biological process whereby specialized sensory receptors convert environmental physical energy (such as light or sound) into neural impulses.

Fovea

The central focal area of the retina that contains an exclusively high density of cone photoreceptors, providing the highest visual acuity and color discrimination.

Rods

Retinal photoreceptors that are highly sensitive in low-light conditions and concentrated in the peripheral retina, but lack the ability to resolve fine detail or color.

Cones

Retinal photoreceptors concentrated in the fovea that function best in bright light and are specialized for color vision and high-acuity spatial resolution.

Trichromatic Theory

The theory of color vision stating that color perception originates from the differential activation of three distinct classes of retinal cone receptors sensitive to short, medium, or long wavelengths.

Opponent-Process Theory

The color vision theory proposing that opposing neural channels (red-green, blue-yellow, black-white) process color signals beyond the retina in the visual cortex.

Dichromatism

A form of color deficiency resulting from the absence or dysfunction of one of the three cone pigment types, commonly causing red-green color blindness.

Proximity (Gestalt)

A Gestalt perceptual grouping principle stating that visual elements positioned close together in space tend to be perceived as belonging to a collective group.

Figure-Ground Segregation

The perceptual organization process by which the visual field is divided into prominent, distinct objects (the figure) and the receding background (the ground).

Binocular Disparity

The subtle difference between the retinal images received by the left and right eyes due to their physical separation, serving as the basis for stereoscopic depth perception.

Ames Room

A specially constructed distorted room that appears rectangular from a fixed viewing peephole, creating a dramatic optical illusion of size disparity between people standing in opposite corners.

Ossicles

The three tiny bones of the middle ear—the malleus (hammer), incus (anvil), and stapes (stirrup)—that mechanically amplify sound vibrations from the tympanic membrane to the cochlea.

Basilar Membrane

A specialized membrane within the cochlea whose base is narrow and stiff to respond to high frequencies, and whose apex is wide and flexible to respond to low frequencies.

Gate Control Model of Pain

A neurological theory proposing that the spinal cord contains a physiological 'gate' that can either block or facilitate the transmission of pain signals to the brain.

Filter Theory of Attention

Donald Broadbent's early-selection model stating that incoming sensory inputs pass through a selective filter based purely on physical characteristics, preventing unattended information from reaching higher-level cognitive analysis.

Cocktail Party Effect

The cognitive phenomenon where an individual can focus their selective auditory attention on a single conversation amid a noisy environment, while still remaining receptive to salient cues like their own name.

Attenuation Theory

Anne Treisman's attention model proposing that unattended sensory messages are weakened or attenuated rather than completely filtered out, permitting highly meaningful stimuli to reach conscious awareness.

Inattentional Blindness

A perceptual failure to notice a fully visible, unexpected object or event because attentional resources are directed elsewhere.

Hemispatial Neglect

A neuropsychological condition, typically following right parietal lobe damage, in which patients fail to attend to, perceive, or replicate objects located in the contralesional left visual field.

Ventral Visual Stream

The cortical visual processing pathway traversing from the occipital lobe to the temporal lobe ('what' pathway), dedicated to object perception, identification, and recognition.

Dorsal Visual Stream

The cortical visual processing pathway running from the occipital lobe to the parietal lobe ('where/how' pathway), specialized for spatial localization and visually guided motor action.

Global Workspace Model

A cognitive neuroscience framework proposing that conscious awareness emerges through synchronized neural communication across a widely distributed network of specialized cortical circuits.

Unresponsive Wakefulness Syndrome

A condition resulting from severe brain damage (formerly termed vegetative state) characterized by intact sleep-wake cycles and physiological arousal, but an absolute absence of conscious awareness.

Locked-In Syndrome

A neurological condition in which full conscious awareness and cognitive function remain intact, but all voluntary muscle control is lost due to brainstem damage, leaving the patient completely paralyzed except for vertical eye movements.

Suprachiasmatic Nucleus (SCN)

A hypothalamic nucleus that receives direct light inputs from the retina to regulate circadian rhythms by signaling the pineal gland to control melatonin synthesis.

Rapid Eye Movement (REM) Sleep

A distinct sleep stage marked by desynchronized, awake-like cortical EEG waves, rapid conjugate eye movements, vivid dreaming, and generalized muscle atonia.

Cataplexy

A sudden, temporary loss of voluntary muscle tone often triggered by intense emotional reactions, commonly manifesting as a hallmark symptom of narcolepsy.

Reticular Activating System (RAS)

A complex network of nuclei and fiber tracts within the brainstem that projects to the thalamus and cortex to maintain cortical wakefulness, arousal, and alertness.

Lysergic Acid Diethylamide (LSD)

A potent synthetic hallucinogenic compound discovered in 1943 by Swiss chemist Albert Hofmann that dramatically alters sensory perception and induces vivid hallucinations.