History, Anatomy, and Methods of Cognitive Neuroscience

Comprehensive vocabulary review flashcards covering the historical origins, cellular neurophysiology, pathways, experimental paradigms, neuroimaging modalities, and hemispheric specializations of cognitive neuroscience.

Monism (Thales)

The philosophical position holding that conscious mental activity is directly a product of the brain's physical activity and not separate from it.

Mind-Body Dualism (Descartes)

The philosophical doctrine proposed by René Descartes asserting that the mind and body/brain are distinct substances, where the non-physical mind performs thought while the physical body operates via mechanical principles.

Thomas Willis

The physician who coined the term 'neurology,' was among the first to link specific focal brain damage to behavioural deficits, and conceptualized early brain information transfer.

Phrenology

A historical movement founded by Franz Joseph Gall stating that the contours of the skull reveal individual cognitive capacities and moral faculties by reflecting underlying brain development.

Aggregate Field Theory

A theory developed by physiologist Pierre Flourens through experimental lesion ablation in animals, asserting that the whole brain participates as a unified collective in behaviour, making complex cognitive functions impossible to localize.

Rationalism

The epistemological view positing that all true knowledge is attained purely through reason and logic alone, rather than sensory experience.

Empiricism

The view that all knowledge originates from sensory experience and empirical experimentation, conceptualizing the newborn mind as a blank slate.

Associationism

An offshoot of empiricism suggesting that higher mental development occurs when simple sensory ideas and elements become linked or associated to form complex concepts.

Localizationist View

The neurological framework championed by John Hughlings Jackson through clinical observations of epileptic seizures, demonstrating topographic organization and specific functional localization in distinct cortical regions.

Broca's Area

A cortical area located in the left inferior frontal lobe crucial for expressive speech production; damage causes Broca's aphasia.

Wernicke's Area

A cortical region located at the junction of the temporal and parietal lobes essential for language comprehension; damage causes receptive Wernicke's aphasia.

Cytoarchitectonics (Korbinian Brodmann)

The structural mapping of the mammalian cerebral cortex into 52 distinct regions based on microscopic cellular organization and histological staining.

Neuron Doctrine

The fundamental concept proven by Santiago Ramón y Cajal establishing that the nervous system consists of discrete individual cellular units where electrical impulses transmit unidirectionally from dendrites to axonal terminals.

Syncytium

The reticular perspective championed by Camillo Golgi claiming that the nervous system is a continuous, interconnected network of shared cytoplasm.

Synapse

The specialized physiological junction between neurons discovered by Sir Charles Sherrington, who also uncovered the mechanisms of reciprocal inhibition in spinal reflexes.

Forgetting Curve

A mathematical relationship established by Hermann Ebbinghaus using nonsense syllables, demonstrating that memory retention declines rapidly after learning and proving that mental processes can be quantified scientifically.

Montreal Procedure

A surgical technique created by Wilder Penfield to treat intractable epilepsy by systematically mapping sensory and motor cortices using direct electrical stimulation in awake patients.

Hebbian Learning Principle

The neuroplasticity law formulated by Donald O. Hebb stating that 'neurons that fire together, wire together,' establishing that simultaneous activation strengthens synaptic connections.

Universal Grammar

The biological framework proposed by Noam Chomsky asserting that humans possess an innate, pre-wired linguistic blueprint that enables rapid language acquisition.

Miller's Law (Short-Term Memory Capacity)

The capacity limit of human working memory identified by George A. Miller as $7 \pm 2$ discrete chunks or items of information.

Patient H.M.

A famous patient who underwent bilateral medial temporal lobe and hippocampal resection to treat epilepsy, demonstrating that the human brain relies on distinct memory systems (declarative vs. procedural).

Working Memory Circuitry (Goldman-Rakic)

The prefrontal microcircuit architecture identified by Patricia Goldman-Rakic that forms the cellular and physiological basis of working memory.

Central Nervous System (CNS)

The primary control center of the nervous system consisting of the brain and spinal cord, responsible for integrating and processing sensory information and issuing motor commands.

Peripheral Nervous System (PNS)

The neural division consisting of cranial and spinal nerves that relays sensory signals from receptors to the CNS and conducts motor commands from the CNS to peripheral targets.

Somatic Nervous System (SNS)

The voluntary motor division of the peripheral nervous system responsible for transmitting motor impulses to skeletal muscles to execute voluntary movements.

Autonomic Nervous System (ANS)

The involuntary division of the peripheral nervous system that innervates cardiac muscle, smooth muscle, and internal glands, subdivided into sympathetic and parasympathetic systems.

Sympathetic Nervous System

The autonomic division that prepares the body for action by elevating heart rate, dilating airways, and mobilizing metabolic energy resources.

Parasympathetic Nervous System

The autonomic division responsible for conserving energy and regulating restorative 'rest and digest' activities, such as slowing heart rate and stimulating digestion.

Dorsal Root Ganglion

A nodular cluster along the posterior spinal nerve root containing the cell bodies of pseudounipolar sensory afferent neurons.

Spinal Reflex Arc

A localized neural circuit consisting of sensory receptor activation, afferent transmission into the spinal cord, interneuron relay, and motor neuron discharge to effector muscles before conscious pain awareness.

Quadriplegia

Complete motor paralysis and sensory loss affecting all four extremities and trunk caused by high spinal cord or severe central brain trauma.

Paraplegia

Motor paralysis and sensory impairment affecting the lower body and legs caused by thoracic or lumbar spinal trauma, while sensation and function of upper limbs and torso remain intact.

Dendritic Spines

Microscopic protruding bulbous structures on neuronal dendrites that function as specialized postsynaptic input sites for synaptic contact.

Axon Collaterals

Side branches diverging from a primary axon shaft that enable a single neuron to send action potentials to multiple post-synaptic targets.

Nodes of Ranvier

Periodic unmyelinated gaps along an axon where dense populations of voltage-gated ion channels allow rapid saltatory conduction.

Unipolar Neuron

A neuron characterized by a single process extending from the cell body, typically functioning as sensory transducers in invertebrates and absent in adult humans.

Bipolar Neuron

A sensory neuron possessing two distinct processes extending from opposite poles of the soma (one axon and one dendrite), specialized for vision, olfaction, and hearing.

Pseudounipolar Neuron

A sensory neuron whose single process bifurcates into peripheral and central axonal branches, found predominantly in dorsal root ganglia.

Multipolar Neuron

The predominant neuronal class in the CNS containing a single axon and numerous dendritic branches, specialized for complex computational integration.

Resting Membrane Potential

The steady-state negative electrical potential across an inactive neuronal membrane, measured at $-70\,\text{mV}$ relative to the extracellular environment.

Sodium-Potassium ($\text{Na}^+/\text{K}^+$) Pump

An active transport membrane pump that hydrolyzes ATP to export $3\,\text{Na}^+$ ions while importing $2\,\text{K}^+$ ions, maintaining negative resting polarity.

Action Potential Threshold

The critical membrane voltage of approximately $-55\,\text{mV}$ required to trigger the rapid opening of voltage-gated sodium channels and elicit an all-or-none spike.

Depolarization

The rising phase of the action potential characterized by a massive influx of positively charged $\text{Na}^+$ ions driving the interior potential up to approximately $+40\,\text{mV}$.

Repolarization

The falling phase of the action potential caused by inactivation of $\text{Na}^+$ channels and opening of voltage-gated $\text{K}^+$ channels, allowing potassium efflux to restore negative potential.

Hyperpolarization (Refractory Period)

The transient phase where delayed closure of $\text{K}^+$ channels causes membrane voltage to dip below $-70\,\text{mV}$, rendering subsequent spike generation impossible or requiring stronger excitation.

Posner's Letter-Matching Task

An experimental paradigm demonstrating that letter processing proceeds hierarchically from low-level visual match (A-A) to higher-level abstract phonetic and category representations.

Sternberg's Memory Comparison Task

A cognitive paradigm demonstrating that reaction time increases linearly with memory set size, proving that short-term memory retrieval operates via serial search rather than parallel search.

Word Superiority Effect

The perceptual phenomenon where individuals identify target letters faster and more accurately when embedded in real words compared to non-words, illustrating parallel top-down feedback.

Stroop Effect

The demonstration of cognitive interference where response latencies are prolonged when naming the ink color of a word printed with an incongruent color name.

Single Dissociation

A neuropsychological finding where a lesion impairs performance on Task A while sparing Task B, indicating specialized processing but vulnerable to task-difficulty confounds.

Double Dissociation

A neuropsychological finding where Patient Group 1 fails Task A but succeeds on Task B, while Group 2 shows the opposite, establishing unequivocal functional independence.

Deep Brain Stimulation (DBS)

A neurosurgical technique involving the chronic implantation of stimulating microelectrodes into subcortical structures (such as the subthalamic nucleus) to alleviate motor symptoms in Parkinson's disease.

Optogenetics

A biological tool combining genetic modification and optics to express light-sensitive channel proteins (e.g., Channelrhodopsin-2 / ChR2) in targeted neurons to control neural firing with light pulses.

Transcranial Magnetic Stimulation (TMS)

A non-invasive technique using electromagnetic induction over the scalp to induce a focal, reversible 'virtual lesion' within a region of approximately $1\,\text{cm}^3$ of cortex.

Diffusion Tensor Imaging (DTI)

A structural MRI methodology that maps white matter tract pathways by tracking the anisotropic diffusion of water molecules along axonal bundles.

Blood Oxygenation Level-Dependent (BOLD) Signal

The contrast mechanism utilized in fMRI based on the magnetic difference between oxyhemoglobin and deoxyhemoglobin following localized surges in metabolic blood flow.

Event-Related Potentials (ERPs)

Averaged, time-locked segments of continuous scalp EEG waveforms evoked by discrete sensory, motor, or cognitive events (such as the P600 syntactic violation shift).

Magnetoencephalography (MEG)

A functional neuroimaging modality utilizing Superconducting Quantum Interference Device (SQUID) helmet sensors to directly register the weak magnetic fields produced by postsynaptic dendritic currents.

Planum Temporale

A structural region on the superior temporal gyrus forming the core of Wernicke's area, exhibiting significant anatomical leftward asymmetry in $65\%$ of adult human brains.

Dichotic Listening Task

An experimental technique presenting competing auditory inputs simultaneously to each ear, revealing a right-ear advantage for speech and a left-ear advantage for non-verbal environmental sounds.

Cognitive Interpreter

A cognitive mechanism specialized in the left hemisphere that formulates causal explanations, connects disparate events, and generates narrative hypotheses.

Alpha Motor Neurons

Large efferent motor neurons located in the spinal cord that innervate extrafusal skeletal muscle fibers and release acetylcholine to evoke physical contraction.

Gamma Motor Neurons

Efferent motor neurons that innervate intrafusal muscle fibers within muscle spindles, regulating stretch receptor sensitivity during dynamic muscle shortening.

Stretch Reflex (Patellar Reflex)

A monosynaptic proprioceptive reflex initiated by tapping a tendon, which activates spindle sensory afferents to elicit contraction of the stretched muscle and reciprocal inhibition of the antagonist muscle.