Fundamental of Cognition Unit 1

introspection

The process through which one "looks within," to observe and record the contents of one's own mental life.

behaviorist movement

Focused on how behavior changes in response to different stimuli ("rewards" and "punishments"). Behaviorists wanted to avoid mentalistic terms (representations or processes inside the mind).

transcendental method

A type of theorizing proposed by the philosopher Immanuel Kant. To use this method, an investigator first observes the effects or consequences of a process and then asks: What must the process have been to bring about these effects?

response time

The amount of time (usually measured in milliseconds) needed for a person to respond to a particular event (such as a question or a cue to press a specific button).

cognitive neuroscience

Understanding humans' mental functioning through study of the brain and nervous system.

clinical neuropsychology

The study of brain function that uses (as its main data source) cases in which damage or illness has disrupted the working of some brain structure

neuroimaging techniques

Non-invasive methods for examining either the structure or the activation pattern within a living brain.

hindbrain

sits on top of the spinal cord and includes structures crucial for controlling key life functions.

cerebellum

The largest area of the hindbrain, crucial for the coordination of bodily movements and balance.

midbrain

It plays an important role in coordinating movements, and it contains structures that serve as "relay" stations for information arriving from the sensory organs

forebrain

It plays a crucial role in supporting intellectual functioning

cortex

The outermost surface of an organ in the body; psychologists are most commonly interested in the brain's cortex and, specifically, the cerebral cortex.

convolutions

The wrinkles visible in the cerebral cortex that allow the large surface area of the human brain to fit into the relatively small volume of the skull.

longitudinal fissure

The separation dividing the brain's left cerebral hemisphere from the right.

cerebral hemisphere

One of the two hemispherical brain structures—one on the left side, one on the right—that constitute the major part of the forebrain in mammals.

frontal lobes

The lobe of the brain in each cerebral hemisphere that includes the prefrontal area and the primary motor projection area.

central fissure

The separation dividing the frontal lobes on each side of the brain from the parietal lobes.

parietal lobe

The lobe in each cerebral hemisphere that lies between the occipital and frontal lobes and includes some of the primary sensory projection areas, as well as circuits that are crucial for the control of attention.

lateral fissure

The separation dividing the frontal lobes on each side of the brain from the temporal lobes.

temporal lobes

The lobe of the cortex lying inward and down from the temples. This lobe in each cerebral hemisphere includes the primary auditory projection area, Wernicke's area, and, subcortically, the amygdala and hippocampus.

occipital lobe

The rearmost lobe in each cerebral hemisphere, and the one that includes the primary visual projection area.

subcortical structures

Pieces of the brain that are under the cortex and are hidden from view. These structures include the thalamus, the hypothalamus, and the various components of the limbic system.

thalamus

A part of the lower portion of the forebrain that serves as a major relay and integration center for sensory information.

hypothalamus

A small structure at the base of the forebrain that plays a vital role in the control of motivated behaviors such as eating, drinking, and sexual activity

limbic system

Includes the amygdala, hippocampus, and parts of the thalamus. Believed to be involved in the control of emotional behavior and motivation, and it also plays a key role in learning and memory.

hippocampus

A structure in the temporal lobe that is involved in the creation of longterm memories and spatial memory.

commissure

One of the thick bundles of fibers along which information is sent back and forth between the two cerebral hemispheres.

corpus callosum

The largest of the commissures linking the left and right cerebral hemispheres

lesion

A specific area of tissue damage

CT scan

A neuroimaging technique that uses X-rays to construct a 3D image of the brain's anatomy

PET scan

A neuroimaging technique that determines how much glucose (the brain's fuel) is being used by specific areas of the brain at a particular moment in time

MRI scan

A neuroimaging technique that uses magnetic fields (created by radio waves) to construct a 3D representation of brain tissue. Like CT scans, MRI scans reveal the brain's anatomy, but they are much more precise than CT scans

fMRI scan

A neuroimaging technique that uses magnetic fields to make a 3D representation of the activity levels in different areas of the brain at a particular moment in time (measures oxygen content in blood flowing through each region of the brain)

EEG scan

A recording of voltage changes occurring at the scalp that reflect activity in the brain underneath

event-related potentials

Changes in an electroencephalogram (EEG) in the brief period just before, during, and after an explicitly defined event, usually measured by averaging together many trials in which this event has occurred

fusiform face area

A brain area apparently specialized for the perception of faces

TMS

A technique in which a series of strong magnetic pulses at a specific location on the scalp causes temporary disruption in the brain region directly underneath this scalp area

localization of function

The research endeavor of determining what specific job is performed by a particular region of the brain

primary motor projection area

The strip of tissue, located at the rear of the frontal lobe, that is the departure point for nerve cells that send their signals to lower portions of the brain and spinal cord, and that ultimately result in muscle movement.

primary sensory projection area

The main point of arrival in the cortex for information arriving from the eyes, ears, and other sense organs

contralateral control

The left half of the brain controls the right half of the body, and the right half of the brain controls the left half of the body

association cortex

The traditional name for the portion of the human cortex outside the motor and sensory projection areas

apraxia

A disturbance in the capacity to initiate or organize voluntary action, often caused by brain damage

agnosia

A disturbance in a person's ability to identify familiar objects (visual and auditory agnosia)

unilateral neglect syndrome

A pattern of symptoms in which affected individuals ignore all inputs coming from one side of space. Individuals with this syndrome put only one of their arms into their jackets, eat food from only half of their plates, read only half of words (e.g., they might read "blouse" as "use"), and so on

aphasia

A disruption to language capacities, often caused by brain damage

neuron

An individual cell within the nervous system

glia

A type of cell found (along with neurons) in the central nervous system. Functions: support neurons, repair neural connections in case of damage, and guiding the initial development of neural connections. A specialized type of glia also provide electrical insulation for some neurons, allowing much faster transmission of neuronal signals

cell body (soma if you want to talk specifics)

The area of a biological cell containing the nucleus and the metabolic machinery that sustains the cell

dendrites

The part of a neuron that usually detects the incoming signal.

axon

The part of a neuron that typically transmits a signal away from the neuron's cell body and carries the signal to another location

neurotransmitter

One of the chemicals released by neurons to stimulate adjacent neurons

synapse

The area that includes the presynaptic membrane of one neuron, the postsynaptic membrane of another neuron, and the tiny gap between them. The presynaptic membrane releases a small amount of neurotransmitter that drifts across the gap and stimulates the postsynaptic membrane

presynaptic membrane

The cell membrane of the neuron "sending" information across the synapse.

postsynaptic membrane

The cell membrane of the neuron "receiving" information across the synapse.

threshold

The activity level at which a cell or detector responds, or fires

action potential

A brief change in the electrical potential of an axon. The action potential is the physical basis of the signal sent from one end of a neuron to the other; it usually triggers a further (chemical) signal to other neurons

myelin sheath

The layer of tissue, formed by specialized glial cells, that provides insulation around the axons of many neurons. There are, however, gaps in this insulation, and the neuronal signal essentially has to "jump" from one gap to the next, dramatically increasing the speed of neurotransmission

all-or-none law

The principle stating that a neuron or detector either fires completely or does not fire at all; no intermediate responses are possible. (Graded responses are possible, however, by virtue of the fact that a neuron or detector can fire more or less frequently, and for a longer or shorter time.)

coding

The system through which one type of information stands for, or represents, a different type of information. In the context of the nervous system, this term refers to the way in which activity in neurons manages to stand for, or represent, particular ideas or thoughts

cornea

The transparent tissue at the front of each eye that plays an important role in focusing the incoming light

lens

The transparent tissue located near the front of each eye that (together with the cornea) plays an important role in focusing incoming light. Muscles control the degree of curvature of the lens, allowing the eye to form a sharp image on the retina

retina

The light-sensitive tissue that lines the back of the eyeball

photoreceptors

Cells on the retina that are sensitive to light and that respond (i.e., send a signal to adjacent cells) when they are stimulated by light

rods

Photoreceptors that are sensitive to very low light levels but that are unable to discriminate hues and that have relatively poor acuity.

cones

Photoreceptors that are able to discriminate hues and that have high acuity. Cones are concentrated in the retina's fovea and become less frequent in the visual periphery.

acuity

The ability to see fine detail.

fovea

The center of the retina and the region on the eye in which acuity is best; when a person looks at an object, they are lining up that object with the fovea

bipolar cells

A type of neuron in the eye. Bipolar cells receive their input from the photoreceptors and transmit their output to the retinal ganglion cells

ganglion cells

A type of neuron in the eye. The ganglion cells receive their input from the bipolar cells, and then the axons of the ganglion cells gather together to form the optic nerve, carrying information back to the lateral geniculate nucleus

optic nerve

The bundle of nerve fibers, formed from the retina's ganglion cells, that carries information from the eyeball to the brain

LGN

An important way station in the thalamus that is the first destination for visual information sent from the eyeball to the brain

lateral inhibition

A pattern in which cells, when stimulated, inhibit the activity of neighboring cells. In the visual system, lateral inhibition in the optic nerve creates edge enhancement

edge enhancement

A process created by lateral inhibition in which the neurons in the visual system give exaggerated responses to edges of surfaces

Mach band

A type of illusion in which one perceives a region to be slightly darker if it is adjacent to a bright region, and also perceives a region to be slightly brighter if it is adjacent to a dark region. This illusion, created by lateral inhibition, contributes to edge enhancement

single-cell recording

A technique for recording the moment-by-moment activation level of an individual neuron within a healthy, normally functioning brain

receptive field

The portion of the visual field to which a cell within the visual system responds. If the appropriately shaped stimulus appears in the appropriate position, the cell's firing rate will change. The firing rate will not change if the stimulus is of the wrong form or is in the wrong position

center-surround cells

A type of neuron in the visual system that has a "donut-shaped" receptive field. Stimulation in the center of the receptive field has one effect on the cell; stimulation in the surrounding ring has the opposite effect

area V1

The site on the occipital lobe where axons from the lateral geniculate nucleus first reach the cerebral cortex. This site is (for one neural pathway) the location at which information about the visual world first reaches the brain

parallel processing

A system in which many steps are going on at the same time. Usually contrasted with serial processing

serial processing

A system in which only one step happens at a time (and so the steps occur in a series). Usually contrasted with parallel processing

what system

The system of visual circuits and pathways leading from the visual cortex to the temporal lobe and especially involved in object recognition

where system

The system of visual circuits and pathways leading from the visual cortex to the parietal lobe and especially involved in the spatial localization of objects and in the coordination of movements

binding problem

The problem of reuniting the various elements of a scene, given that these elements are initially dealt with by different systems in the brain

neural synchrony

A pattern of firing by neurons in which neurons in one brain area fire at the same time as neurons in another area; the brain seems to use this pattern as an indication that the neurons in different areas are firing in response to the same stimulus

conjunction error

An error in perception in which a person correctly perceives what features are present but misperceives how the features are joined, so that (for example) a red circle and a green square might be misperceived as a red square and a green circle

gestalt principles

A small number of rules that seem to govern how observers organize the visual input, grouping some elements together but perceiving other elements to be independent of one another.

perceptual constancy

The achievement of perceiving the constant properties of objects in the world (e.g., their size, shape, and color) despite changes in the sensory information we receive that are caused by changes in our viewing circumstances

size constancy

The achievement of perceiving the constant size of objects despite changes in the size of the retinal image that result from variations in viewing distance

shape constancy

The achievement of perceiving the constant shape of objects despite changes in the shape of the retinal image that result from variations in viewing angle

brightness constancy

The achievement of perceiving the constant brightness of objects despite changes in the light reaching the eye that result from variations in illumination

unconscious inference

The hypothesized steps that perceivers follow in order to take one aspect of the visual scene (e.g., viewing distance) into account in judging another aspect (e.g., size)

distance cues

Information available to the perceiver that allows the perceiver to judge how far off a target object is

binocular disparity

A distance cue based on the differences between the two eyes' views of the world. This difference becomes less pronounced the farther away an object is from the observer

monocular distance cues

Features of the visual stimulus that indicate distance even if the stimulus is viewed with only one eye

pictorial cues

Patterns that can be represented on a flat surface to create the sense of a three- dimensional object or scene

interposition

A monocular distance cue that relies on the fact that objects farther away are blocked from view by closer objects that happen to be in the viewer's line of sight

linear perspective

A cue for distance based on the fact that parallel lines seem to converge as they get farther away from the viewer

motion parallax

A distance cue based on the fact that as an observer moves, the retinal images of nearby objects move more rapidly than do the retinal images of objects farther away

optic flow

The pattern of change in the retinal image in which the image grows larger as the viewer approaches an object and shrinks as the viewer retreats from it