Cognitive Neuroscience, Cortical Development, and Memory Systems

Comprehensive vocabulary flashcards covering cognitive tasks, neuroimaging methodologies, corticogenesis, developmental psychology paradigms, and memory systems from Modules 1 through 4.

Experimental Psychology — Primary Dependent Measures

Reaction time ($\text{RT}$) and accuracy (error rate), which quantify the processing speed and precision of mental operations.

Reaction-Time ($\text{RT}$) Distribution — Key Mathematical Properties

Positively skewed (skewed to the right), showing a dense cluster of fast responses and a prolonged tail of slower trials.

Speed-Accuracy Trade-off Principle

Forcing faster response latencies directly increases error rates because subjects lower their internal decision thresholds.

Posner Letter-Matching Task — Mental Representations Finding

Demonstrates that visual input is transformed into multiple internal representations progressing from low-level physical traits to abstract phonetic and categorical codes.

Posner Letter-Matching Task — Reaction Time Latency Hierarchy

Responses are fastest for physically identical pairs ($AA$), intermediate for phonetically identical pairs ($Aa$), and slowest for same-category pairs ($AU$).

Sternberg Item-Recognition Task — Memory Retrieval Mechanism

Retrieval from short-term memory operates via an exhaustive serial search where the mental list is evaluated item by item.

Sternberg Item-Recognition Task — Reaction Time Curve

Reaction time displays a strictly linear increase for every additional item placed into the memorized set, showing identical slopes for target-present and target-absent trials.

Stroop Task — Cognitive Mechanism

Demonstrates that deeply overlearned, automatic processes (reading word text) interfere with and slow down controlled processes (naming ink color).

Word-Superiority Effect — Top-Down Influence

Demonstrates top-down cognitive facilitation: target letters are identified faster and more accurately inside a real word than in isolation or nonsense strings.

Brain Lesion Method — Core Inference Limitations

Naturally occurring brain injuries rarely respect neat anatomical boundaries, mass effects can distort remote circuits, and neural plasticity can trigger compensatory masking.

Brain Tumors (Gliomas vs. Meningiomas) — Impact on Lesion Localization

Meningiomas compress adjacent cortex externally from the meninges without tissue invasion, whereas gliomas infiltrate parenchyma directly, making precise boundary mapping difficult.

Single Dissociation — Definition and Weakness

A patient group shows deficit on Task 1 while performing normally on Task 2; confounded by the fact that Task 1 might merely be more difficult.

Double Dissociation — Structural Definition

Patient Group A fails Task 1 but passes Task 2, while Group B passes Task 1 but fails Task 2, proving that the two tasks rely on independent neural systems.

Contra-coup Brain Injury — Biomechanical Cause

Contusion localized on the side opposite the initial impact site, produced when the cerebrum rebounds and decelerates against the opposite inner cranial wall.

Single-Unit Recording — Electrophysiological Methodology

Inserting a microelectrode adjacent to an individual neuronal membrane to measure extracellular action potential firing rates and determine receptive field properties.

Multi-Barreled Micropipette (Microiontophoresis) — Function

Uses minute electric currents to eject precise micro-quantities of ionized neurotransmitters or drugs onto an isolated single neuron while monitoring electrical responses.

Structural MRI — Physical Image Acquisition Mechanism

Applies powerful magnetic fields and radiofrequency ($\text{RF}$) pulses to perturb hydrogen protons in tissue water, tracking relaxation times to render soft-tissue anatomy.

Functional MRI (fMRI) — Physiological Basis of the BOLD Signal

Measures the Blood Oxygen Level-Dependent ($\text{BOLD}$) contrast, detecting local changes in the ratio of oxygenated to deoxygenated hemoglobin driven by the hemodynamic response.

Functional MRI (fMRI) — Spatial and Temporal Resolution

Provides millimeter-level spatial resolution ($\sim 1\text{--}3\,\text{mm}$) but poor temporal resolution ($2\text{--}6\,\text{seconds}$) due to hemodynamic lag.

Positron Emission Tomography (PET) — Mechanism of Action

Injects unstable positron-emitting isotopes (such as $^{18}\text{F-FDG}$) that collide with electrons, releasing detectable gamma rays to map regional cerebral blood flow and glucose metabolism.

Positron Emission Tomography (PET) — Spatial and Temporal Resolution

Yields moderate spatial resolution ($\sim 5\text{--}10\,\text{mm}$) but very poor temporal resolution (minutes) and carries tracer radiation risks.

Scalp Electroencephalography (EEG) — Primary Electrical Generator

Detects the synchronized postsynaptic dendritic potentials of large cohorts of geometrically aligned, perpendicular cortical pyramidal neurons.

Scalp Electroencephalography (EEG) — Spatial and Temporal Resolution

Delivers millisecond-level temporal resolution but poor spatial resolution due to signal smearing across the skull and the inverse localization problem.

Imaging Resolution Rule — EEG vs. fMRI Comparison

Scalp electroencephalography ($\text{EEG}$) provides superior temporal precision (milliseconds), whereas functional magnetic resonance imaging ($\text{fMRI}$) provides superior spatial localization (millimeters).

Parkinson’s Disease — Neuropathology and Primary Symptoms

Loss of dopaminergic neurons in the substantia nigra pars compacta of the basal ganglia, resulting in resting tremor ($4\text{--}6\,\text{Hz}$), rigidity, and bradykinesia.

Huntington’s Disease — Neuropathology and Symptom Profile

Degeneration of striatal medium spiny neurons in the caudate nucleus and putamen, producing involuntary hyperkinetic choreiform movements.

Pick’s Disease (Frontotemporal Dementia) — Neuropathology and Onset

Frontal and temporal cortical atrophy marked by intracellular tau Pick bodies, presenting early with personality shifts, loss of social inhibition, and aphasia before episodic memory loss.

Alzheimer’s Disease — Neuropathology and Initial Symptom Presentation

Widespread extracellular amyloid-beta plaques and intracellular tau neurofibrillary tangles, characteristically emerging as severe anterograde episodic memory impairment.

Blastula to Embryo — Two Primary Morphogenetic Steps

Gastrulation (reorganizing the blastula into three primary germ layers) and neurulation (forming the neural tube and crest).

Primary Germ Layers — Tissue Destinations

Ectoderm produces epidermis and the nervous system; mesoderm forms muscle, bone, and blood; endoderm forms internal visceral linings of the gut and lungs.

Neurulation — Origins of the CNS and PNS

Infolding of the embryonic ectoderm creates the neural tube, which differentiates into the central nervous system, and the neural crest, which forms the peripheral nervous system.

Ventricular Zone (VZ) — Progenitor Division Types

Precursor cells divide symmetrically to expand the stem pool, then transition to asymmetric division to generate one postmitotic migratory neuron and one self-renewing progenitor.

$^{3}\text{H}$-Thymidine Labeling Technique — Histogenetic Timecourse

Radioactive thymidine incorporates into newly replicating DNA during S-phase to permanently mark a neuron's exact birthdate and identify its final laminar destination.

Inside-Out Cortical Migration Gradient

Deep cortical layers (Layer VI) are established first; later-born cohorts migrate outward past older neurons to assemble superficial layers (Layers II–IV).

Radial Glial Cells — Dual Function in Corticogenesis

Provide elongated structural guides for migrating postmitotic neuroblasts during cortical assembly and subsequently differentiate into fibrous and protoplasmic astrocytes.

Reeler Mice Experiment — Biochemical Defect and Phenotype

Deficiency in the extracellular protein reelin causes newly migrating neurons to stall beneath older cohorts, creating an inverted outside-in cortical layout.

Microsurgical Cell Transplantation — Autonomy of Laminar Fate

Transplanting early-born precursor cells into older embryonic hosts reveals that laminar fate is pre-programmed at final cell division, as cells still settle in deep layers.

Radial Unit Hypothesis (Pasko Rakic) — Structural Dimensions

The number of precursor radial units in the ventricular zone dictates total cortical surface area, while the number of cell division cycles per unit dictates cortical thickness.

Protomap Hypothesis (Pasko Rakic) — Regional Specification

Proposes that functional areal divisions of the adult neocortex (such as primary visual or motor cortex) are genetically mapped in the ventricular zone prior to neuroblast migration.

Cognitive Schemes (Jean Piaget) — Definition

Organized mental patterns or internal representations utilized to categorize, interpret, and respond to incoming environmental stimuli.

Assimilation vs. Accommodation — Piagetian Mechanism

Assimilation integrates novel environmental experiences into existing schemes without modification; accommodation alters or creates new schemes when new data conflicts.

Sensorimotor Stage ($0\text{--}2\,\text{years}$) — Key Cognitive Milestone

Infants construct knowledge through direct physical interactions and sensory feedback, culminating in the gradual emergence of object permanence.

Preoperational Stage ($2\text{--}7\,\text{years}$) — Key Features and Limitations

Characterized by rapid symbolic representation and language acquisition, but constrained by egocentrism, perceptual centration, and failure on conservation tasks.

Concrete Operational Stage ($7\text{--}11\,\text{years}$) — Hallmark Abilities

Children master logical, reversible operations applied to tangible physical objects, successfully achieving conservation, seriation, and classification.

Formal Operational Stage ($11+\,\text{years}$) — Hallmark Abilities

Development of abstract propositional logic, hypothetical-deductive problem solving, and systematic counterfactual reasoning.

Competence vs. Performance Distinction — Developmental Controversy

Contrasts an infant's true underlying cognitive knowledge (competence) with their capacity to demonstrate that knowledge through motor task execution (performance).

Manual Pointing vs. Preferential Looking Paradigms

Infants fail to reach manually for hidden items until $8\text{--}12\,\text{months}$ due to motor limits, but display longer preferential looking at impossible events as early as $3.5\,\text{months}$.

René Baillargeon — Violation-of-Expectation Paradigm

Showed that $3.5\text{-month-old}$ infants look reliably longer at physically impossible events (such as a rotating screen passing through a hidden solid block), confirming early object permanence.

Judy DeLoache — Dual Representation Hypothesis

Young children struggle with scale models because they fail to represent a miniature room simultaneously as a physical object and as a symbolic stand-in for the full-sized room.

Gretchen Van de Walle — Infant Ordinality Findings

Demonstrated that preverbal infants possess innate numerical sensitivity to relative ordinal relationships, recognizing that 3 items represent greater magnitude than 2 items.

Adele Diamond — Neurobiology of the $A\text{-not-}B$ Search Error

Attributed infant perseverative reaching at location $A$ to the protracted maturation of the dorsolateral prefrontal cortex, which governs working memory maintenance and inhibitory control.

Alexander Luria — Prefrontal Functional Contribution

Established through lesion cases that the prefrontal cortex constitutes the tertiary motor zone, responsible for programming actions, regulating goal-directed behavior, and verifying performance.

Phineas Gage — Lesion Localization and Behavioral Outcome

Damage localized to the orbitofrontal and ventromedial prefrontal cortex, leading to profound loss of executive control, social disinhibition, and drastic personality changes.

Patient H.M. (Henry Molaison) — Surgical Resection Boundaries

Bilateral resection of the medial temporal lobes, removing the anterior two-thirds of the hippocampi, parahippocampal gyrus, entorhinal cortices, and amygdalae.

Patient H.M. (Henry Molaison) — Amnesic Profile

Profound, permanent anterograde amnesia for declarative information accompanied by temporally graded retrograde amnesia sparing remote early childhood memories.

Patient H.M. (Henry Molaison) — Preserved Cognitive Capacities

Intact short-term digit span, preserved perceptual priming, unimpaired vocabulary and IQ, and preserved non-declarative procedural learning on mirror-drawing tasks.

Declarative (Explicit) vs. Non-Declarative (Implicit) Memory Systems

Declarative memory involves conscious, verbalizable recall of facts and episodes mediated by the medial temporal lobes; non-declarative memory operates unconsciously through behavioral execution.

Episodic Memory vs. Semantic Memory

Episodic memory stores personally experienced autobiographical events situated in specific times and places; semantic memory contains decontextualized factual knowledge and concepts.

Procedural Memory — Function and Primary Substrates

Non-declarative memory supporting automated sensorimotor skills and motor habits, mediated predominantly by the basal ganglia and cerebellum.

Priming — Definition and Primary Substrates

A form of non-declarative memory in which prior perceptual or conceptual exposure facilitates subsequent stimulus processing, mediated primarily by the neocortex.

Baddeley Secondary Task Paradigm — Working Memory Dissociation

A concurrent working memory load significantly impairs new declarative encoding and complex reasoning, but only slows retrieval latency without impairing retrieval accuracy.

Student Review Question — Why Does Secondary Task Load Hurt Memory Encoding More Than Retrieval?

Encoding requires active central executive working memory to assemble and bind novel memory traces, whereas retrieval relies on cue-driven distributed neocortical access that is robust to executive load.