PSYCH 414 Unit 1 Exam FINAL

cerebral achromatopsia

inability to perceive color; V4 lesion

akinetopsia

inability to perceive motion; V5 lesion

Albert’s Line-Cancellation Task

An adaptation of a clinical assessment task used to evaluate spatial neglect; patients with hemispatial/left visual neglect typically cancel only lines on the right side of the page and miss those on the left.

allocentric localization

spatial visual localization relative to other landmarks/objects

AMPA Receptor

A primary type of ligand-gated glutamate receptor that opens Na+ channels upon glutamate binding to depolarize postsynaptic cells.

Anterior Commissure

A mediolateral-oriented tract located rostral to the hippocampus carrying transhemispheric axons between the anterior temporal lobes.

Apical Dendrite

A long main dendritic trunk projecting upward from the apex of a pyramidal cell soma towards layer I.

Apperceptive Agnosia

A form of visual agnosia characterized by an inability to form a coherent perceptual representation of objects due to disrupted mid-level visual processing, image segmentation, feature integration, or Gestalt grouping, while basic feature detection remains intact. Patients show impaired performance on tasks like the unusual views test or shadows test.

Area OC

The neuroanatomical atlas label corresponding to striate cortex (V1).

Areas OB and OA

Neuroanatomical atlas labels corresponding to extrastriate occipital cortical areas.

Area PG

A neuroanatomical atlas label corresponding to posterior and inferior parietal cortex (part of the dorsal stream), bounded dorsally by the intraparietal sulcus.

Areas TEO and TE

Neuroanatomical atlas labels corresponding to regions within the inferior temporal (IT) cortex (part of the ventral stream).

Associative Agnosia

A form of visual agnosia where perceptual visual representations are formed correctly (can copy drawings or describe shapes), but cannot be linked to semantic memory or object knowledge ("perception stripped of its meaning").

associationism

knowledge builds from sensory info linked by contiguity or similarity

Astrocytes

Glial cells adjacent to glutamate synapses that take up released glutamate, convert it to a precursor metabolite, and transfer it back to neurons.

atmospheric perspective

distant objects

A pictorial depth cue where distant objects appear less sharp, lower in contrast, and slightly blueish due to light scattering by atmospheric dust and moisture particles.

Attention

The cognitive mechanism that selects specific sensory information for continued, focused cognitive processing; it is both selective and resource-limited. Core dimensions/aspects of attention include

Selectivity

awareness of only a subset of stimuli.

Capacity Limitations

limited ability to handle multiple tasks/stimuli at once (divided attention). Sustained Mental Effort

Control

exogenous vs. endogenous attentional control.

Domain

spatial attention vs. object-based attention.

Attentional Benefits and Costs (Posner)

In spatial cueing tasks, benefits are calculated by subtracting reaction times to expected/valid signals from neutral signals, while costs are calculated by subtracting neutral reaction times from unexpected/invalid signals.

Attentional Control Mechanisms (Posner’s Tripartite Model)

Posner’s theory of spatial attention control involving three sequential operations

Disengage

Release attentional focus/grip from the current stimulus/location.

Move

Shift/refocus the attentional spotlight to a new target location.

Engage

Grasp/begin attending to the new stimulus.

Attentional Filter

An early selective mechanism proposed by Broadbent (1958) that blocks unattended incoming sensory information from reaching higher-level semantic processing based on physical cues (e.g., pitch, location).

Attentional Spotlight

The concept that spatial attention acts as an adjustable beam or spotlight, enhancing sensory processing for stimuli falling within its locus.

Attenuation Theory (Treisman)

An intermediate selection model proposing that unattended inputs are not completely blocked, but rather attenuated (partially turned down). Unattended information can still reach threshold if primed or highly salient (e.g., one's own name).

Automatic Process

A cognitive process requiring minimal to no attentional capacity that runs to completion involuntarily and without conscious intent once triggered by appropriate environmental stimuli (Shiffrin & Schneider, 1977).

Axon

A projecting branch extending from the neuron base that propagates electrical action potentials to transmit signals to other neurons.

Axon Hillock

The conical region where the cell body funnels down into the axon, containing high concentrations of voltage-gated Na+ channels to initiate action potentials.

Basal Dendrites

Dendritic branches sprouting from the lower corners/base of a pyramidal cell soma.

Behaviorism

An objective, experimental branch of natural science dominant in American psychology from the 1920s to the 1950s. Founded by John Watson, it rejects introspection and consciousness as unscientific, arguing instead that psychology should focus strictly on observable behavior, explain behavior rather than thought, keep theories simple, and break behavior down into basic building blocks like conditioned reflexes. It frequently used the technological metaphor of a telephone switchboard to describe brain input-output functions.

Binocular Disparity

The difference between the two slightly different 2D images projected onto the left and right retinas due to the horizontal separation of the eyes; closer objects produce larger disparity.

Blocking (Classical Conditioning)

A phenomenon in classical conditioning where prior pairing of a stimulus prevents learning of a second paired stimulus, demonstrating that animals learn only when events violate expectations, generating prediction errors.

Bottom-Up Processing ("Feed Forward")

Data-driven perceptual processing that begins with raw, unprocessed sensory input on the retina and systematically constructs complex object representations by progressively building up basic feature properties before assigning semantic meaning.

Brightness

The perceived intensity of light reflected from or emitted by a surface.

Broadbent’s Filter Theory

An early-selection filter model proposing that physical sensory characteristics are processed for all inputs, but a selective bottleneck filter blocks unattended information from semantic processing early in the processing stream.

Calcium Ions (Ca++)

Ions concentrated outside the cell; influx through voltage-gated Ca++ channels at presynaptic terminals triggers neurotransmitter release.

Capacity Limitations

A fundamental aspect of attention reflecting the human mind's limited ability to process multiple tasks or stimuli simultaneously (divided attention).

Caudal

Towards the tail or back end of the brain/spinal cord.

Central Nervous System (CNS)

The core system of the nervous system consisting of the spinal cord, brainstem, cerebellum, and cerebrum. During embryonic development, all elements derive from the neural plate/tube.

central sulcus

divides frontal/parietal lobe (anterior/posterior)

Cerebellum

A distinct structure situated inferior to the occipital lobe responsible for motor control and coordination.

Cerebral Cortex (Neocortex)

A thin (roughly 2.5-mm-thick) 2-D sheet of tissue with a surface area of about 2500 cm2 that covers the five lobes of the cerebrum. It represents a relatively new feature of the CNS in evolutionary terms and is organized into six functional layers.

Cerebrospinal Fluid (CSF)

Fluid filling the ventricles and bathing the internal and external surfaces of the brain and spinal cord under pressure, gently inflating the brain from within.

Cerebrum

The main bulk of the brain consisting of two hemispheres, divided into five lobes

Chemical Disequilibrium

The uneven distribution of ions across the cell membrane at rest

Cherry (1953)

The study introducing dichotic listening experiments, finding that listeners can track an assigned message but fail to notice semantic changes (e.g., foreign language, backward speech) in the unattended ear, while still detecting basic low-level physical alterations (e.g., pitch change, pure tones).

Classical Conditioning

A training procedure and form of learning where a conditioned stimulus (e.g., a bell) is repeatedly paired with an unconditioned stimulus (e.g., food) until the conditioned stimulus alone elicits a conditioned response (e.g., salivation).

Closure

A Gestalt principle of organization where the visual system fills in missing boundaries or gaps to perceive whole, enclosed shapes.

Cocktail Party Effect

The phenomenon where an individual selectively attends to one conversation in a noisy environment but rapidly shifts attention when a highly salient semantic stimulus—such as their own name—occurs in an unattended stream.

Cognitive Psychology

A science of mental processes that studies how the mind takes in, transforms, manipulates, stores, and outputs information, using abstract constructs (representations and processes) to characterize stages of information processing.

Cognitive Revolutions / Approaches

An approach inferring internal mental representations and processes from observable stimulus-response behavior, assuming computational models of mind.

Complex System

A system (like the brain) where constituent parts interact nonlinearly, giving rise to emergent, self-organized properties where the whole differs from the simple sum of its parts.

Computer Metaphor

A foundational analogy in cognitive psychology viewing the human mind as analogous to a computer, where both take in information, manipulate representations via internal processes (analogous to software), and produce responses or behaviors using physical hardware (the brain).

Conditioned Reflex

A learned, automatic response to a stimulus produced through experience and training (classical conditioning), proposed by Watson and Pavlov as a candidate for the basic building block of behavior.

Conditioned Response

A response elicited by a conditioned stimulus after learning has taken place through classical conditioning; it is often similar to the unconditioned response.

Conditioned Stimulus

An initially neutral stimulus that evokes little or no response on its own, but comes to elicit a conditioned response after being repeatedly paired with an unconditioned stimulus.

Conjunction Search

A visual search paradigm where target items are defined by a combination of two or more visual features (e.g., blue AND horizontal) or spatial arrangements. Reaction time increases linearly as the number of items in the display increases, reflecting serial analysis of the visual display.

Continuous Task

A task that presents an uninterrupted stream of incoming stimuli requiring ongoing sensory monitoring and continuous response outputs (e.g., tracking a moving target).

Convergence

An oculomotor depth cue where the two eyes rotate inward (cross) to keep a target object centered on the foveas; the degree of inward turning provides information about close distances.

Coronal Plane

A vertical cross section plane dividing the brain into front (anterior) and back (posterior) sections.

Corpus Callosum

A thick band/bundle of millions of myelinated axons connecting neurons of the left and right hemispheres across the midline.

Correction trial

A trial in a behavioral task administered after an error trial, where the same stimulus array is re-presented with the incorrect food well uncovered so the subject receives feedback that no reward was present.

Cortical area MT (Middle Temporal Area)

A cortical visual area characterized in cross section by heavy myelination of fibers even after they enter the cortex. It receives direct visual input from layer IVB spiny stellate neurons in V1, as well as indirect input from V2 thick stripes.

Cortical area V2

An extrastriate visual cortical area containing distinct cytochrome oxidase staining patterns consisting of thick stripes, thin stripes, and interstripes. The thick stripe region receives projections from V1 layer IVB pyramidal neurons and projects to area MT.

Cortical Columns

Stacks or groups of interconnected neurons extending vertically from layer II/III to VI that are more strongly connected internally than with adjacent non-column neurons.

Craik & Watkins (1973)

A classic memory experiment demonstrating that simple maintenance rehearsal (holding an item in mind for varying durations) does not predict long-term recall performance.

Critical Period

A specific window of time in an organism's development during which its nervous system is genetically primed to learn particular information (such as chicks learning to identify their mother); if missed, acquiring that information later becomes difficult or impossible.

Cueing Paradigm (Posner)

An experimental task measuring spatial attention where cues (valid, neutral, or invalid) precede targets; valid cues produce faster reaction times (attentional benefits) while invalid cues slow reaction times (attentional costs).

Dendrites

Branching extensions of a neuron that act as antennae to receive chemical/electrical signals from other axons.

Dendritic Spines

Submicron-sized protrusions studding dendritic branches where synaptic contacts are formed.

Depolarization

A positive shift in membrane potential towards 0 mV (e.g., from -70 mV toward -20 mV), increasing the likelihood of firing an action potential.

Depth Cues

Environmental and physiological visual cues used by the visual system to determine how far away an object is.

Dichotic Listening Task

A selective attention task where different auditory messages are delivered simultaneously to each ear through headphones, requiring the participant to continuously shadow (repeat aloud) the message in one designated ear.

Dimensions of Color

The three psychological attributes used to define color perception

Direct pathway (LGN to MT)

A pathway where magnocellular signals travel from LGN to layer IVCα of V1, then to layer IVB spiny stellate neurons, which project directly to area MT.

Discrete Task

A task with a distinct, unambiguous start and endpoint, usually separated from subsequent trials by a pause.

Disjunctive Search (Feature Search)

A visual search task where a target is defined by a single unique feature (e.g., finding a blue line among red lines); reaction time is independent of display size, demonstrating automatic parallel processing and "pop-out".

Disengage

The specific step in Posner's attention model involving releasing the attentional grip from a current location or object.

Distributed Representation

A neural coding scheme in which a specific concept or visual object is represented by patterns of activity spread across broad populations of neurons and brain regions, rather than localized to a single isolated module.

Distractors

Unintended background items present in a visual search display or memory array that compete with the target item for attention.

Domain of Attention

A dimension distinguishing between spatial-based attention (attention focused on spatial locations) and object-based attention (attention focused on perceived object structures).

Dorsal

In bipedal humans, refers to the "back" (posterior) of the spinal cord and the "top" (superior) of the brain.

Dorsal Stream

The visual pathway extending from primary visual cortex to the posterior parietal cortex, specialized for spatial perception ("where") and action guidance ("how").

Double dissociation of function

A key principle of experimental inference in neuropsychology where damage to brain area A selectively impairs performance on task X but leaves task Y intact, while damage to brain area B selectively impairs performance on task Y but leaves task X intact. This demonstrates that the two brain regions support specific, distinct functional systems.

Dual-Task Paradigm

An experimental setup requiring participants to perform two tasks concurrently to assess attentional capacity limits, resource sharing, and processing bottlenecks.

Early Filter Theory

Donald Broadbent's model proposing that physical sensory characteristics are processed for all stimuli, but a selective bottleneck filter blocks unattended information from semantic processing early in the stream.

Ecological Approach

A theory of perception proposed by J.J. Gibson arguing that the rich structure of the natural environment provides direct, sufficient information for action and navigation without requiring complex internal computational inferences.

Egocentric localization

Spatial visual localization defined using a self-centered frame of reference, where the position of an object is anchored in reference to the observer's own body position.

Electrical Disequilibrium

The baseline state of a resting neuron maintaining a negative voltage of approximately -70 mV across its membrane relative to the extracellular space.

Empiricism

The philosophical view (advocated by Hobbes, Locke, Berkeley, Hume, James Mill, and John Stuart Mill) that all knowledge comes from experience that shapes an impressionable mind.

Encoding

The cognitive process of converting sensory information into internal mental representations.

Endogenous Attention

Voluntary, goal-directed, slow, and volitional control of attention driven by internal goals and expectations.

Engage

The final step in Posner's attention model where focus is locked onto a new stimulus location.

Epstein (1965)

A classic study demonstrating that familiar size acts as a distance cue (using equal-sized, equidistant photos of different coin denominations), showing that familiar size cues influence size and distance perception most reliably when viewed under binocular or contextual conditions.

Ethology

The scientific study of animal behavior in natural habitats (rather than laboratory settings), which provided early evidence against the "blank slate" view by documenting innate behaviors like fixed-action patterns and critical periods.

Exogenous Attention

Fast, transient, automatic, and reflex-driven attentional capture triggered by external stimuli.