psych 260 test 2

Ablation

The destruction or removal of tissue in the nervous system

Action pathway

Determines how a person carries out an action

Area V1

Another name for the visual receiving area

Complex cells

Cells that respond only when a correctly oriented bar of light moves across the entire receptive field

Contextual modulation

The effect of stimulating outside the receptive field

Contralateral

The opposite side of the visual field

Contrast threshold

The minimum intensity difference between two adjacent bars that can just be detected

Cortical magnification

The apportioning of a large area on the cortex to the small fovea

Cortical magnification factor

The size of the cortical magnification

Dorsal pathway

Another name for the where pathway, refers to the top of the brain

Double dissociations

In one person, damage to one area of the brain causes function A to be absent while function B is present; in the other person, damage to another area of the brain causes function B to be absent while function A is present

End-stopped cell

A cell that fires to moving lines of a specific length or to moving corners or angles

Experience-dependent plasticity

The idea that the response properties of neurons can be shaped by perceptual experience

Extrastriate cortex

Areas outside the striate cortex known as V2, V3, V4, and V5

Feature detectors

Simple, complex, and end-stopped cells that fire in response to specific features of the stimulus, such as orientation or direction of movement

Hippocampus

An area associated with forming and storing memories

How pathway

Determines how a person carries out an action

Hypercolumn

A location column with all of its orientation columns

Inferotemporal (IT) cortex

Neurons in this area in the temporal lobe have the largest receptive fields

Landmark discrimination problem

A monkey's task was to remove the cover of the food well that was closest to the "landmark"

Lateral geniculate nucleus (LGN)

A part of the brain that receives approximately 90 percent of the signals from the retina

Location columns

Columns with neurons that have their receptive fields at the same location on the retina

Neural plasticity

The idea that the response properties of neurons can be shaped by perceptual experience

Object discrimination problem

A monkey was shown one object, such as a rectangular solid, and was then presented with a two-choice task

Optic chiasm

An x-shaped bundle of fibers on the underside of the brain

Orientation columns

Columns containing cells that respond best to a particular orientation

Orientation tuning curve

The relationship between a neuron's orientation and firing

Retinotopic map

The electronic map of the retina on the cortex

Selective adaptation

Firing causes neurons to eventually become fatigued or adapt

Selective rearing

The idea that if an animal is reared in an environment that contains only certain types of stimuli, then neurons that respond to these stimuli will become more prevalent

Simple cortical cell

Cells with these side-by-side receptive fields

Striate cortex

Another name for the visual receiving area

Superior colliculus

A structure involved in controlling eye movements

Tiling

A series of columns covering the entire visual field

Ventral pathway

Another name for the what pathway, refers to the lower part of the brain

Visual receiving area

The place where signals from the retina and LGN first reach the cortex

What pathway

The pathway leading from the striate cortex to the temporal lobe

Where pathway

The pathway leading from the striate cortex to the parietal lobe

Apparent movement

Movement that is perceived when nothing is actually moving

Bayesian inference

The estimate of the probability of an outcome is determined by two factors: the prior probability and the likelihood

Binocular rivalry

A situation in which the observer perceives either the left-eye image or the right eye image, but not both at the same time

Border ownership

The property of the border belonging to one area

Decoder

A computer program that can predict the most likely stimulus based on the voxel activation patterns observed

Expertise hypothesis

The idea that our proficiency in perceiving faces, and the large face response in the FFA, can be explained by the fact that we have become "experts" in perceiving faces

Extrastriate body area (EBA)

Activated by pictures of bodies and parts of bodies, but not by faces or other objects

Figural cues

Cues within the image that determine which areas are perceived as a figure

Figure

A separate object that stands out from its background

Figure-ground segregation

When we see a separate object, it is usually seen as a figure that stands out from its background, which is called the ground

Fusiform face area (FFA)

An area of the brain located in the fusiform gyrus on the underside of the brain directly below the inferotemporal (IT) cortex

Geons

Individual geometric components

Gestalt psychologist

A school of thought that rejected the idea that perceptions were formed only by "adding up" sensations

Gist of a scene

A general description of a type of scene

Global image features

Features that can be perceived rapidly and are associated with specific types of scenes

Ground

A background to a figure

Grouping

The process by which elements in a visual scene are "put together" into coherent units or objects

Illusory contour

An edge that appears present when there are actually no physical edges present

Inverse projection problem

The task of determining the object responsible for a particular image on the retina

Lateral occipital complex (LOC)

An area of the brain that is active when the person views any kind of object

Light-from-above assumption

The assumption that light is coming from above because light in the environment usually comes from above

Likelihood

The extent to which the available evidence is consistent with the outcome

Likelihood principle (Helmholtz)

States that we perceive the object that is most likely to have caused the pattern of stimuli that we have received

Multivoxel pattern analysis (MVPA)

An analysis of the pattern of activation across multiple voxels

Neural mind reading

Using a neural response, usually brain activation measured by fMRI, to determine what a person is perceiving or thinking

Object recognition

The process of detecting the objects in an image and then matching those objects to existing, stored representations of what those objects are

Parahippocampal place area (PPA)

A specialized area in the temporal lobe that responds to places but not objects or faces

Perceptual organization

The process by which elements in a person's visual field become perceptually grouped and segregated to create a perception

Persistence of vision

The perception of a visual stimulus continues for about 250 ms (1/4 second) after the stimulus is extinguished

Physical regularities

Regularly occurring physical properties of the environment

Pragnanz

Translated from the German, this term means "good figure"

Prediction

The idea that our past experiences help us make informed guesses about what we will perceive

Predictive coding

A theory that describes how the brain uses our past experiences to predict what we will perceive

Principle of common fate

Things that are moving in the same direction appear to be grouped together

Principle of common region

Elements that are within the same region of space appear to be grouped together

Principle of good continuation

Points that, when connected, result in straight or smoothly curving lines are seen as belonging together, and the lines tend to be seen in such a way as to follow the smoothest path

Principle of good figure

Every stimulus pattern is seen in such a way that the resulting structure is as simple as possible. Also called the principle of pragnanz, or the principle of simplicity

Principle of pragnanz

Every stimulus pattern is seen in such a way that the resulting structure is as simple as possible. Also called the principle of good figure, or the principle of simplicity

Principle of proximity (nearness)

Things that are near each other appear to be grouped together

Principle of similarity

Similar things appear to be grouped together

Principle of simplicity

Every stimulus pattern is seen in such a way that the resulting structure is as simple as possible. Also called the principle of pragnanz, or the principle of good figure

Principle of uniform connectedness

A connected region of the same visual properties, such as lightness, color, texture, or motion, is perceived as a single unit

Principles of perceptual organization

A set of principles that determine how elements in a scene become grouped together

Prior/prior probability

Our initial estimate of the probability of an outcome

Prosopagnosia

Difficulty recognizing the faces of familiar people

Recognition by components (RBC) theory

A theory that objects are comprised of individual geometric components called geons, and we recognize objects based on the arrangement of those geons

Regularities in the environment

Characteristics of the environment that occur frequently

Reversible figure-ground

An image that can be perceived alternately either as two dark blue faces looking at each other, in front of a gray background, or as a gray vase on a dark blue background

Scene

A view of a real-world environment that contains background elements and multiple objects that are organized in a meaningful way

Scene schema

Knowledge of what a given scene typically contains

Segregation

The process of separating one area or object from another

Semantic regularities

Characteristics associated with activities that are common in different types of scenes

Spatial layout hypothesis

Proposes that the PPA/PHC responds to the surface geometry or geometric layout of a scene

Structuralism

A school of thought that distinguished between sensations—elementary processes that occur in response to stimulation of the senses—and perceptions, more complex conscious experiences such as our awareness of objects

Unconscious inference

Our perceptions are the result of unconscious assumptions, or inferences, that we make about the environment

Viewpoint invariance

The ability to recognize an object seen from different viewpoints

Visual masking

Reduction or elimination of the visibility of one brief stimulus

\#TheDress

The online address for a picture of a dress that is seen as alternating blue and black stripes by some people and as alternating white and gold stripes by others

Aberration

Imperfections on the eye's cornea and lens that distort light on its way to the retina

Achromatic colors

Color without hue. White, black, and all the grays between these two extremes are achromatic colors

Adaptive optical imaging

A technique that makes it possible to look into a person's eye and take pictures of the receptor array in the retina

Additive color mixture

The creation of colors that occurs when lights of different colors are superimposed