HP2600 Chapter 10 Visual Imagery

visual imagery

seeing in the absence of a visual stimulus

paired-associate learning

learning procedure in which pairs of words are presented and a subject is later asked to recall the second word when cued with the first word from the pair

conceptual peg hypothesis

idea that concrete nouns create images that other words can hang onto

mental chronometry

determining the amount of time needed to carry out a cognitive task

mental scanning

creation of mental images and then scanning them in one's mind

imagery debate

debate about whether imagery is based on spatial or propositional (language) mechanisms

spatial representation

representations in which different parts of an image correspond to specific locations in space

depictive representation

spatial representations in which the parts of the representation correspond to parts of the object

propositional representations

representations in which relationships can be represented by abstract symbols

epiphenomenon

a secondary phenomenon that accompanies a primary phenomenon as a by-product

imagery neurons

neurons that fire in the same way when imagining or perceiving an object

possible evidence of physiological mechanism for imagery

brain imaging

- shows that both perception and imagery activate the visual cortex

- strong overlap of activation caused by perception and imagery in front of the brain (frontal lobe), but some difference near the back of the brain (occipital lobe)

multivoxel pattern analysis (MVPA)

technique for determining pattern of voxel activation for a particular stimulus

voxel: unit of graphic information defining a point in 3D space

unilateral neglect

condition caused by damage to parietal lobes which causes a person to ignore objects in one half of their visual field

differences between imagery and perception

- perception is automatic while imagery is effortful

- perception is stable and continuous while imagery is fragile and can vanish without continued effort

- manipulation of mental images more difficult than perceptual images

method of loci

method in which things to be remembered are placed at different locations in a mental image of a spatial layout

imagery improves memory by creating organised locations for specific items in memory

pegword technique

memory technique whereby ordered items to be remembered are associated with concrete words that can be imagined

e.g. number-word pair of one-bun -> item 1 associated with mental image of a bun

spatial imagery

ability to image spatial relations

measured by:

- paper folding task

- mental rotation task

object imagery

ability to image visual details and objects

measured by:

- vividness of visual imagery questionnaire (VVIQ)

- degraded pictures task

aphantasia

inability to visualise imagery

hyperphantasia

ability to visualise imagery extremely vividly

synaesthesia

condition in which sensations of one modality trigger sensations of another modality

single unit recording

open brain procedure used to measure responses of single neurons

transcranial magnetic stimulation (TMS)

technique that disrupts normal brain functioning in a particular brain area for a short time