PSYC 3310: Memory & Cognition - Complete Course Study Guide
Foundations and Scope of Cognitive Psychology
Course Identification: PSYC 3310 Memory & Cognition, instructed by Dr. Holly Bowen.
Definition of Cognitive Psychology:
Cognitive psychology is the scientific study of the mental processes involved in three primary cognitive domains:
Acquiring and Storing Information: Includes sensory perception, selective attention, and memory encoding and storage mechanisms.
Manipulating Information: Includes language production and comprehension, decision-making processes, logical reasoning, and mental visualization.
Using Existing Knowledge in New Situations: Includes creative thinking, problem-solving, and categorizing novel environmental information.
Every cognitive function relies on "hidden" underlying mental processes that operate automatically outside of conscious awareness.
Core Methodological Considerations:
Defining cognitive psychology and establishing its scientific framework.
Addressing the foundational debate since the early 1900s: How is it possible to study the inner workings of the mind when mental processes cannot be directly observed?
Methodological approach to studying unobservable mental operations:
Measure directly observable behavior.
Make logical inferences regarding the underlying cognitive activity.
Evaluate what behavioral metrics reveal about the structural and functional principles of the mind.
Examining the origins and impact of the cognitive revolution.
Investigating how cognitive psychological principles directly apply to everyday human experience.
Historical Pioneers and Early Experimental Cognitive Psychology
Franciscus Donders (1868) — Reaction Time and Decision Making:
Conducted the earliest experiments measuring the time required for a human to make a decision.
Simple Reaction Time (RT) Task: Participants were instructed to press a button as quickly as possible upon observing a single light stimulus.
Choice Reaction Time (RT) Task: Participants were instructed to push one specific button if a light appeared on the right side, and a different button if the light appeared on the left side.
Mathematical Formula for Decision Time:
Empirical Finding: Choice RT was found to be (or ) longer than Simple RT.
Core Theoretical Conclusion: Mental responses cannot be measured directly; they must be inferred from observable behavior.
Wilhelm Wundt (1879) — Structuralism and Analytic Introspection:
Established the world's first laboratory of scientific psychology at the University of Leipzig, Germany.
Theoretical Approach — Structuralism: Postulated that overall conscious experience is determined by combining basic, elementary elements of experience termed sensations.
Experimental Method — Analytic Introspection: A technique in which rigorously trained participants were instructed to describe their conscious sensory experiences and thought processes in detail in response to controlled stimuli.
Hermann Ebbinghaus (1885) — Memory Retention and Forgetting Curves:
Investigated memory retention and decay by reading lists of nonsense syllables (e.g., DAX, QEH) aloud repeatedly until he could recite the lists without error.
Relearned the identical lists after varying retention delay intervals.
Quantified memory retention using the Savings equation:
Key Findings:
Shorter retention delay intervals required significantly fewer repetitions to relearn the list, yielding higher savings.
Plotted savings as a function of retention interval to construct the Savings Curve, demonstrating that rates of forgetting are rapid initially and then level off over time.
The Rise and Principles of Behaviorism
John B. Watson (Early 1900s) — Rejection of Introspection:
Founded the theoretical framework of Behaviorism.
Rejected Wundt's analytic introspection method based on two primary critiques:
Introspective methods produced extremely variable and inconsistent results across individual participants.
Results were inherently subjective and impossible to independently verify because internal mental events are unobservable.
Core Behaviorist Doctrine: Eliminated the unobservable "mind" as a subject of psychological study, arguing instead that psychology should focus exclusively on directly observable behavior.
Ivan Pavlov — Classical Conditioning:
Discovered classical conditioning through animal learning paradigms.
Mechanism: A neutral event is repeatedly paired with an unconditioned event that naturally produces a specific response.
Outcome: After repeated pairings, the previously neutral event evokes the response independently.
Watson and Rayner (1920) — The "Little Albert" Experiment:
Demonstrated classical conditioning of fear in a infant.
Paired the presentation of a neutral white rat with a sudden, loud noise.
After repeated stimulus pairings, the child developed a conditioned fear response to the white rat alone.
Proved that complex human behaviors and emotional states could be analyzed and modified without referencing internal mental processes.
B. F. Skinner (1930s to 1960s) — Operant Conditioning:
Focused on quantifying the precise relationships between environmental stimuli and behavioral responses.
Operant Conditioning Framework: Shaped behavior via environmental rewards (reinforcements) or punishments.
Behavior followed by favorable consequences (rewards) is reinforced and increases in frequency.
Behavior followed by unfavorable consequences (punishments) decreases in frequency.
The Fall of Behaviorism and Re-Emergence of the Mind
Edward Chace Tolman (1948) — Cognitive Mapping in Rats:
Trained rats to navigate a four-armed maze to locate food rewards.
Experimental Paradigm:
Step 1: Rats freely explored all arms of the maze.
Step 2: Rats were placed at Position A and food was placed at Position B; the rats were rewarded for turning right.
Testing Step: Rats were placed at Position C to observe their navigational choice.
Competing Theoretical Hypotheses:
Behaviorist Hypothesis: Rats learned a mechanical stimulus-response motor response ("turn right to find food").
Tolman's Cognitive Hypothesis: Rats created an internal visual/spatial mental layout—a cognitive map—of the maze and would navigate directly to Position B.
Experimental Result: The rats turned left from Position C to navigate directly to Position B where food was previously located. This supported Tolman's hypothesis and contradicted the strict behaviorist interpretation.
The Language Acquisition Controversy (Skinner vs. Chomsky):
B. F. Skinner (1957) — Verbal Behavior: Argued that children acquire language entirely through operant conditioning principles (imitating heard speech and receiving environmental rewards for grammatically correct utterances).
Noam Chomsky (1959) — A Review of B. F. Skinner's Verbal Behavior:
Disproved Skinner's behaviorist model, demonstrating that language acquisition cannot be explained solely by imitation and reinforcement.
Key empirical evidence:
Children routinely generate novel statements they have never heard before (e.g., "Mommy I hate you!") and thus cannot be imitating.
Children express incorrect grammatical constructions that have never been rewarded or reinforced.
Theoretical conclusion: Language acquisition is driven by an inborn biological program hardwired into human neuroanatomy.
The Cognitive Revolution and Information-Processing Framework
The Cognitive Revolution:
A major paradigm shift away from the behaviorist focus on stimulus-response associations toward an approach aimed at explaining observable behavior through underlying mental mechanisms.
Information-Processing Approach:
Directly influenced by the invention and development of commercial digital computers in the 1950s.
Formulated a model of human cognition derived from computer architecture, postulating that the mind processes incoming environmental information in sequential stages.
Timeline of Key Events (1948–1967):
1948: Edward Chace Tolman demonstrates cognitive maps in maze navigation.
1953: E. Colin Cherry conducts foundational Dichotic Listening experiments:
Presented Message A to the participant's left ear and Message B to the right ear.
Instructed participants to "shadow" (repeat aloud) the target message from one ear.
Demonstrated that participants can selectively focus their attention exclusively on the shadowed message while filtering out the unattended message.
1954: The first commercial digital computer becomes available.
1956: Key scientific conferences at Dartmouth and MIT assemble researchers to lay the groundwork for cognitive science and artificial intelligence.
1957: B. F. Skinner publishes Verbal Behavior.
1958: Donald Broadbent designs the first structural flow diagram model of attention:
Represented cognitive processes as stage-based flow diagrams.
Showed that unattended sensory information is blocked by an internal attentional filter and fails to pass through for higher-level processing.
1959: Noam Chomsky publishes his critique of Skinner's Verbal Behavior.
1967: Ulric Neisser publishes Cognitive Psychology, writing the first textbook in the field and officially coining the term "cognitive psychology".
Cognitive Neuroscience and Levels of Analysis
Definition: Cognitive neuroscience is the scientific study of the physiological basis of cognition, integrating the study of the full nervous system with the cellular units that comprise it.
Theoretical and Practical Importance:
Illuminates the physiological mechanisms that underlie behavioral observations (providing a explanatory "how").
Identifies direct correlations between physical brain activity and internal mental states.
Validates and solidifies psychological theories using physiological data.
Advances understanding of neuroplasticity and how behavioral experiences shape neural anatomy.
Guides clinical decisions regarding mental health interventions and neurological treatments.
Generates key empirical findings for clinical conditions, including Parkinson's Disease, Alzheimer's Disease, Depression, and Autism.
Levels of Analysis Framework:
Cognitive phenomena must be examined from multiple perspectives and angles rather than a single viewpoint.
Integrating findings across physiological scales yields a comprehensive understanding of human cognition.
Progression of analytical levels:
Perception and Memory Example (Gil and Mary):
Perceiving: When Gil perceives Mary during a conversation, physiological mechanisms can be described at the level of chemical reactions, single neuron firings, localized brain structure activity, and coordinated activity across distributed brain networks.
Remembering: When Gil subsequently remembers his meeting with Mary, these same integrated levels of physiological analysis apply.
Gross Neuroanatomy and Cellular Communication
Gross Neuroanatomy Basics:
Structural organization: Consists of the Left Hemisphere and Right Hemisphere.
Cerebral Cortex: A thick outer cellular layer wrapping the brain, housing structures responsible for higher-order cognitive processing.
Four Primary Cortical Lobes:
Frontal Lobe: Responsible for executive control, reasoning, motor function, and language production.
Parietal Lobe: Processes somatosensory information and spatial integration.
Temporal Lobe: Responsible for auditory processing, memory encoding, and complex visual recognition.
Occipital Lobe: Primary center for visual processing.
Major associated subcortical and structural components include the Brain Stem and Cerebellum.
Cellular Anatomy of Neurons:
Neurons are specialized cells designed to create, receive, and transmit electrical and chemical signals within the nervous system.
Structural components:
Cell Body (Soma): Contains metabolic machinery required to keep the neuron alive.
Axon: A fluid-filled cylindrical tube that transmits electrical signals (action potentials) away from the cell body toward other neurons.
Dendrites: Multiple branching structures extending from the cell body that receive incoming chemical signals from adjacent neurons.
Historical Evolution of Neural Concepts:
Nerve Net Theory: Early 19th-century view holding that the nervous system consisted of a continuous, uninterrupted net of interconnected pathway tubes.
Camillo Golgi: Developed a staining technique using silver nitrate (Golgi stain) that completely stained a small fraction of individual neurons.
Santiago Ramón y Cajal: Utilized Golgi staining to evaluate tissue under microscopic examination.
Disproved Nerve Net Theory, establishing that individual nerve cells are structurally independent units.
Formulated the Neuron Doctrine: The principle that individual cells transmit signals throughout the nervous system and are not physically continuous with other cells.
Discovered the Synapse: The microscopic gap separating the axon terminal of one neuron from the dendrites or cell body of another neuron.
Neural Signaling Dynamics and Coding Principles
Sensory Receptors:
Specialized neurons designed to pick up physical energy from the external environment and convert it into electrical signals (e.g., cutaneous touch receptors).
Action Potential Physiology:
Resting Potential:
State in which the neuron is not actively firing or receiving inputs.
The electrical charge inside the axon is relative to the outside environment.
Action Potential Generation:
Triggered when the neuron receives a threshold stimulus from the environment or adjacent neurons.
An electrical impulse travels down the axon length, causing the internal charge to rapidly rise to relative to the outside.
Repolarization:
As the impulse propagates down the axon, the internal charge rapidly falls back toward the negative resting baseline.
Synaptic Transmission:
Reaching the axon terminal triggers the release of chemical messengers called neurotransmitters into the synaptic gap.
Neurotransmitters diffuse across the synapse and bind to receptor sites on post-synaptic dendrites, initiating action potential generation in adjacent neurons.
Neural Coding of Stimulus Intensity:
The height and magnitude of an action potential remain constant during transmission.
Stimulus intensity is encoded by the firing rate (frequency of action potentials over time):
Low Stimulus Intensity: Slow, low-frequency firing rate.
High Stimulus Intensity: Fast, high-frequency firing rate.
Neural Representations, Feature Detectors, and Population Coding
Principles of Internal Representation:
Definition of the Mind: An internal cognitive system that creates representations of the external world to enable goal-directed action.
Principle of Neural Representation: Everything an individual experiences is based not on direct contact with reality, but on internal representations constructed within the nervous system.
Feature Detectors and Hierarchical Processing:
Hubel and Wiesel (1960s):
Recorded single-cell electrical activity in the visual cortex of cats exposed to visual stimuli on projection screens.
Discovered Feature Detectors: Visual cortex neurons that respond selectively to specific stimulus properties (e.g., orientation, bars, edges, or movement).
Hierarchical Processing Framework:
Feature detectors in the primary visual cortex serve as basic foundational building blocks.
Outputs from lower-level feature detectors project to higher cortical visual areas where signals combine and interact.
Progressive ascension from lower to higher brain regions corresponds to perceiving objects of increasing structural complexity (from simple lines to complex visual forms).
Coding Patterns in the Brain:
Distributed Representations:
Complex perceptions activate widespread, distributed cortical areas working in parallel.
Example (Perceiving a Rolling Ball): Separate distributed regions process depth, spatial location, motion, color, and shape simultaneously.
Population Coding:
The representation of a specific visual or cognitive object by the distinct pattern of electrical firing across a large population of neurons.
Empirical evidence shows that the precise number of activated neurons depends on the content, individual neural architecture, and environmental context.
Localization of Function and Language Processing Centers
Localization of Function Principle:
Specific cognitive functions are localized within and served by specific regions of the brain.
Structural damage to dedicated areas causes specific, predictable breakdowns in cognitive performance.
Supported by clinical research in Neuropsychology (the study of behavioral alterations in individuals with localized brain damage).
Cortical Language Centers:
Broca's Area:
Discovered by Paul Broca (1861) following post-mortem analysis of patient "Tan", who retained language comprehension but could only express the word "tan".
Anatomical Location: Left frontal lobe.
Clinical Deficit: Damage causes Broca's aphasia—impaired speech production and fluency despite intact language comprehension.
Wernicke's Area:
Discovered by Carl Wernicke (1879) in patients exhibiting fluent, grammatically structured speech that was meaningless and incoherent.
Anatomical Location: Left temporal lobe.
Clinical Deficit: Damage causes Wernicke's aphasia—impaired language comprehension with preserved speech production fluency.
Methodology of Double Dissociation:
Demonstrates that two cognitive functions operate via separate, independent neural mechanisms.
Occurs when damage to brain area X abolishes Function A while Function B remains intact, AND damage to brain area Y abolishes Function B while Function A remains intact.
Application to Language Systems:
Left frontal lobe lesions disrupt speech production while sparing language comprehension.
Left temporal lobe lesions disrupt language comprehension while sparing speech production.
Neuroimaging Methodologies and Functional Specialization
Brain Imaging Modalities:
Electroencephalography / Event-Related Potentials (EEG / ERP): Records electrical activity at the scalp.
Positron Emission Tomography (PET): Tracks metabolic activity using injected radioactive tracers.
Magnetoencephalography (MEG): Measures localized magnetic fields generated by brain activity.
Computed Tomography (CT SCAN) and X-Ray: Radiologic structural imaging.
Magnetic Resonance Imaging (MRI): Provides high-resolution structural images of brain anatomy.
Functional Magnetic Resonance Imaging (fMRI): Measures active brain function over time during specific cognitive operations.
fMRI Mechanisms and Subtraction Logic:
BOLD Signal (Blood Oxygen-Level Dependent):
Neuronal activation increases localized blood flow and oxygen usage.
Hemoglobin contains ferrous iron, giving it magnetic properties that vary depending on whether it is oxygenated or deoxygenated.
Scanners measure changes in the BOLD signal based on oxygenated versus deoxygenated blood flow ratios in active brain regions.
Subtraction Analysis:
Most functional localization analyses utilize subtraction protocols.
Baseline BOLD activity (resting state) is subtracted from task-state BOLD activity to remove background noise and isolate task-specific activations.
Conceptually derived from the subtraction principles of Donders' reaction time experiments.
Specialized Visual Processing Modules:
Fusiform Face Area (FFA):
Located in the temporal lobe; responds specifically to human faces.
Damage to the FFA results in prosopagnosia (the inability to recognize familiar faces).
Parahippocampal Place Area (PPA):
Located in the temporal lobe; responds specifically to spatial contexts, including indoor and outdoor visual scenes.
Extrastriate Body Area (EBA):
Responds specifically to images of human bodies and body parts (excluding facial features).
Neural Networks and Functional Connectivity:
Distributed Processing Complementarity: Complex high-level cognitive processes rely on widespread, distributed neural networks rather than isolated structures; localization of function and distributed processing represent complementary principles.
Neural Network: Interconnected groups of neurons or macro-level brain structures that continuously communicate.
Functional Connectivity:
Measures the extent to which neural activity in distinct, distributed brain areas is correlated over time during cognitive tasks.
Analyzed by assessing correlated functional activity across regions (e.g., distinct network activation patterns when processing an emotional face versus a neutral face).