Visual Imagery

Anderson and Bower (1973)

• Single representation system in which we store both verbal and visual information as propositions

• Propositions are abstract, language-like in form

• Imagery is epiphenomenal

  • The images you generate are secondary; a byproduct of underlying processes; plays no causal role

analog code

• code that resembles the physical object; visual-spatial representation

  • Preserves the spatial properties of what is represented

symbolic code

• code that is descriptive; propositional representation

  • Stores information as abstract, language-like statements

mental rotation studies

• the ability to mentally rotate an object and distinguish it

  • It takes a longer amount of time to rotate an object more

Shepard and Metzler (1974)

participants would see two objects and have to judge if they were the same or different

• If mental object rotation works the same time as physical object rotation, objects with higher degrees of rotation should take longer to identify

image scanning

people shift their attention or transform a visual mental image across an imagined object or map, taking time proportional to the physical distance being covered

• Kosslyn et al. (1978)

Kosslyn et al. (1978)

• Memorized the map

• Asked to mentally ‘travel” from one landmark to another

• Response when “arrived”

  • found that mentally travelling longer distances took a longer amount of time

image scaling studies

• Ability to see finer details depending on distance (depth of perception)

Kosslyn (1978)

• Think of a rabbit next to an elephant: can’t recall as many details of the rabbit because the elephant is bigger/closer

  • fewer details

• Think of a rabbit next to a fly: can “see” more details on the rabbit because it’s bigger/closer

• Able to notice fur texture, eye features, etc. when close up

  • more details

Le Bihan et al. (1993)

• Used fMRI to examine brain activity in the primary visual cortex (occipital lobe)

• Examined for presented vs. imagined stimuli

Kreimnn et al. (2000)

• Single-cell recordings 

• Electrodes implanted in epileptic patients

• Single-cell responses to presented stimuli

• Same cells’ responses to imaginations

Luzatti (1978)

• Damage to right parietal lobe

• Neglect left half of visual world

• Also neglect left half of images

Ganis et al. (2004)

• Comprehensive fMRI study

• Activity in front, middle, vs rear of brain

• Activity for perception vs imagery

Kosslyn et al. (1999)

• Transcranial magnetic stimulation (TMS)

  • Decreases brain functioning in a particular area of the brain for a short time

  • If behavior is disrupted, the deactivated part of the brain is causing that behavior

  • TMS to visual area of brain during perception and imagery task 

  • Response time slower for both

  • Brain activity in the visual area of the brain plays a causal role for both perception and imagery

Dissociations between imagery and perception

• R.M.

  • Damage to occipital lobe and parietal lobes

  • Could draw accurate pictures pf objects in front of him

  • Could not draw accurate pictures of objects from memory (using imagery)

• C.K.

  • Inability to name pictures of objects, even his own drawings, in front of him

  • Could draw objects in great detail from memory (using imagery)

• Conclusion: not perfect overlap

  • Perception involves sensory input and knowledge

    • Bottom-up and top-down processing

    • Perception requires lower and higher visual centers

  • Imagery involves knowledge, no sensory input

    • Just top-down processing

    • Just higher visual centers

concreteness effect

Memory for pictures:

• Shepard (1967): 612 pictures and tested

• Standing (1973): 10k pictures over 5 days

  • Remembered over 6000 pictures

Picture superiority effec

remembering something better in picture form than in word form

benefit of imagery instructions (Bower and Winzenz (1970))

bizarre imagery effect

• remembering something better if it’s a bizarre situation

  • McDaniel et al. (2000)

    • Ex: the woman spilled MILK on the TABLE→imagery better

    • Ex: The woman licked MILK off of the TABLE→bizarre better

apllications of imagery

• Imagery with a substitution

  • Name learning

  • foreign word learning

name learning

• Think of a vivid word that sounds like the name

• Link word with the person's appearance

foreign word learning

• Think of a vivid word that sounds similar

• Link the word with its meaning through imagery

Method of Loci

• Eogknew

• Walking through something in your mind you’re familiar with

Pegword Mnemonic

•  associate information with a well-known rhyming scheme

  • The most common form allows you to learn information in groups of 10

why do loci/pegword methods work?

• Distinctiveness

• Organization