psych 2

Sensation

When your senses detect information around you.

Perception

When your brain figures out what sensory information means.

Divide-and-conquer strategy

The brain breaks sensory information into smaller parts to process it.

Phototransduction

When light is turned into electrical signals in the retina.

Rods

Cells in the eye that help us see in low light.

Cones

Cells in the eye that help us see colors and details.

Rhodopsin

A light-sensitive chemical found in rods.

Photopsins

Light-sensitive chemicals found in cones.

Retina

The part of the eye that detects light.

Optic nerve

Carries visual information from the eye toward the brain.

Optic chiasm

Where some visual nerve fibers cross to the opposite side.

Ipsilateral

On the same side.

Contralateral

On the opposite side.

LGN

A part of the thalamus that sends visual information to V1.

V1

The first main part of the visual cortex that processes visual information.

Retinotopic mapping

Nearby things we see are represented in nearby brain areas.

Magnocellular cells

Large LGN cells that help process movement and brightness changes.

Parvocellular cells

Smaller LGN cells that help process colors and fine details.

Receptive field

The area where a stimulus can affect a particular neuron.

ON-center receptive field

Responds best when light hits the center rather than the surrounding area.

OFF-center receptive field

Responds best when light hits the surrounding area rather than the center.

Orientation selectivity

When a brain cell responds best to a line facing a certain direction.

Orientation columns

Groups of nearby brain cells that respond to similar line directions.

Ocular dominance columns

Areas in V1 that respond more strongly to one eye than the other.

Binocular disparity

The small difference between what each eye sees that helps us judge depth.

V4-related areas

Brain areas involved in seeing colors.

Achromatopsia

A condition where someone loses normal color vision.

MT/V5

A brain area important for seeing movement.

Akinetopsia

A condition where someone has trouble seeing movement.

Shape from motion

Using movement to figure out an object's shape.

Motion parallax

Nearby objects seem to move faster than faraway objects when we move.

Multimodal perception

When the brain combines information from different senses.

McGurk effect

When what we see changes what we think we hear.

Synesthesia

When one experience automatically causes an additional sensory experience.

Brain plasticity

The brain's ability to change and adapt based on experience.

Blindfolding study

Temporary blindfolding showed that visual brain areas can help process touch.

Object recognition

The brain's ability to identify what an object is.

Multidimensional vision

The brain separates visual information into parts like color, shape, and motion.

Flexibility and robustness

Recognizing objects even when their appearance changes.

Memory bound

Using stored knowledge and past experiences to recognize objects.

Goal of object recognition

To identify things around us and respond appropriately to survive.

Ventral pathway

The what pathway that helps us recognize objects.

Dorsal pathway

The where/how pathway that helps locate objects and guide movements.

Ungerleider and Mishkin monkey study

Temporal damage hurt object recognition, while parietal damage hurt spatial tasks.

Object discrimination

A task that tests whether someone can recognize the correct object.

Landmark discrimination

A task that tests whether someone can determine an object's location.

Lesion

Damage to a part of the brain.

Ablation

Deliberately removing or destroying part of the brain during an experiment.

Single dissociation

When brain damage affects one task more than another.

Double dissociation

When two different brain lesions cause opposite patterns of problems.

Why is double dissociation important?

It gives stronger evidence that different brain areas handle different functions.

Auditory cat study

Different auditory brain regions were important for identifying and locating sounds.

Visual agnosia

Trouble recognizing objects by sight even though basic vision works.

Optic ataxia

Trouble using vision to guide reaching movements accurately.

Visual agnosia vs. optic ataxia

Agnosia affects recognition; optic ataxia affects visually guided reaching.

Patient D.F.

She struggled to judge a slot's direction but could correctly put a card through it.

Object constancy

Recognizing an object even when its appearance changes.

Shape encoding

How the brain represents an object's shape and features.

Cue invariance

Recognizing something even when visual clues change.

Multistable percepts

When the same image can be interpreted in different ways.

Rubin's vase

An image that can look like either a vase or two faces.

Grandmother cell hypothesis

The idea that individual neurons respond to very specific people or objects.

Jennifer Aniston cells

Highly selective neurons that responded to images of Jennifer Aniston.

Ensemble coding

When many neurons work together to represent an object.

Graceful degradation

When brain damage causes a gradual loss of ability rather than complete failure.

Encoding

When the brain turns a stimulus into patterns of neural activity.

Decoding

Using neural activity to predict what someone is seeing or experiencing.

Support vector machine

A computer method used to separate and classify patterns of brain activity.

Decoding dreams

Using brain activity to make limited predictions about dream content.

Apperceptive visual agnosia

Trouble forming an accurate visual picture of an object.

Integrative visual agnosia

Can see individual parts but struggles to combine them into a whole.

Associative visual agnosia

Can see an object's shape but cannot connect it to what the object is.

Holistic processing

Recognizing a face using its overall appearance rather than separate features.

FFA

Fusiform Face Area; helps process face identity.

OFA

Occipital Face Area; helps process facial features.

PPA

Parahippocampal Place Area; responds strongly to scenes and places.

EBA

Extrastriate Body Area; helps process body parts.

FBA

Fusiform Body Area; helps process overall body shape.

Electrical stimulation of FFA

Can distort face perception, showing that face-selective regions help us see faces.

Prosopagnosia

Face blindness; difficulty recognizing familiar faces.

Capgras syndrome

Believing a familiar person has been replaced by an identical impostor.

Prosopagnosia vs. Capgras

Prosopagnosia affects face recognition; Capgras involves believing someone is an impostor.

VWFA

Visual Word Form Area; helps recognize familiar written letters and words.

Pure alexia

Serious difficulty reading despite relatively preserved spoken language abilities.

Neuronal recycling hypothesis

The brain reuses existing circuits to learn new skills like reading.

Orthographic

Related to written letters and words.

Nonorthographic

Not related to written language, such as pictures or unrelated symbols.