Imagery and Perception

Visual Imagery: The experience of visual perception in the absence of a direct visual stimulus. This is exhibited when an object or scene can be perceived mentally even when it is not visually present.
- Example: Ruben is walking across campus and thinking about Susan's book left at home; he imagines seeing it on his desk.
Related Concepts:
- Episodic Memory: Involves recalling specific experiences, such as climbing the Eiffel Tower and remembering the view of Paris.
- Semantic Memory: General knowledge about the world.
- Mental Time Travel: A characteristic of episodic memory, which allows recalling past events.

Engage in practical exercises to stimulate visual imagery:
- Count windows in your home.
- Recall items from your breakfast table.
- Determine the shape of an elephant’s ears (rounded or pointy).

Visual Imagery: "Seeing" in the absence of a visual stimulus.
Auditory Imagery: Imagining melodies or sounds in the mind.
Mental Imagery: Encompasses experiencing sensory impressions without sensory input, applicable to tastes and smells too.
Importance: Offers dimensions of thinking that complement verbal techniques.

Development of methods to measure behavior to infer cognitive processes, illustrated by:
- Alan Paivio’s (1963) Study:
- Found that concrete nouns (e.g., truck, tree) are easier to remember than abstract nouns (e.g., justice).
- Related to the Picture Superiority Effect seen in Chapter 7.
Shepard and Metzler (1971):
- Introduced mental chronometry, measuring the time taken to perform cognitive tasks.
- Example: Participants identified whether two pictures depicted the same object; the time taken was proportional to angle differences between views.
- Implication: Suggests shared mechanisms between imagery and perception, raising questions of similarity and differences.

Perception: The process of making sense of environmental stimuli through senses.
Spatial Perception: Awareness of spatial relationships regarding the orientation of one’s body amidst distractions.
Visual-Object Imagery: The representation of visual characteristics of objects (shape, color, texture).
Spatial Imagery: Representation of relations among objects, including their locations and movements.

Shepard and Metzler’s Experiments:
- Found spatial correspondence between imagery and perception through tasks requiring mental rotations of objects.
Kosslyn (1973) and Mental Scanning: Participants took longer to navigate images over greater distances, supporting spatial imagery concepts.

Supported the perspective that visual imagery operates through Spatial Representation:
- Different parts of an image correspond to specific locations in space.

Proposed that imagery is primarily Propositional:
- Representations are abstract symbols, such as statements (e.g., “The cat is under the table”).
- Contrast with Spatial Representation, which might be depicted similar to real images.

Kosslyn's Boat Example: Propositional in nature despite spatial relationships.
- Demonstrated how different pathways between parts affect speed in scanning.

Tacit Knowledge Explanation: People simulate real-world knowledge to inform their mental images, which influences reaction time in imagery tasks.
- Finke and Pinker (1982): Experiment used brief visual stimuli followed by inquiries, demonstrating longer response times over greater mental distances.

Kosslyn's Animal Experiment (1978):
- Participants answered faster about details regarding a larger animal when it filled more visual space, bringing forth spatial properties of mental imagery.
Mental Walk Task:
- Participants estimated their distance to a mental image of an animal, showing real spatial dynamics.

Farah (1985): Connection between imagery and perception established through participant tasks involving letter visualization.

Bottom-Up and Top-Down Processes:
- Perception: Reliance on sensory inputs.
- Imagery: Lacks visual input, impacting brain activation timings and areas.

Kreiman, Koch, and Fried (2000):
- Investigated neurons in epileptic patients, revealing neurons that respond to both visual stimuli and imagined objects, termed imagery neurons.
Primary Visual Cortex Activations:
- Showed activation from both real perception and imagined images (Le Bihan et al. 1993).

Ganis, Thompson, and Kosslyn (2004):
- Highlighted shared brain regions activated during perception and imagery, alongside notable differences in processing intensity.
Amedi, Malach, and Pascual-Leone (2005):
- Explored non-visual processing deactivation during imagery.

M.G.S.: Impact of right occipital lobe removal on ability to visualize distances of imagined objects.
Unilateral Neglect: Patients exhibit visual neglect in both perception and imagery, indicating simultaneous brain impacts.

Documented cases show differing abilities due to distinct cognitive mechanisms:
- R.M.: Normal perception but impaired imagery.
- C.K.: Normal imagery despite severely impaired perception.

Most consensus on shared mechanisms with distinctions in operation:
- Perception is automatic; imagery is more labor-intensive.
- Imagery can become ephemeral.
Pearson and Kosslyn (2015): Acceptance of flexible representations based on task demands.
- Highlight disparity among cognitive styles, affecting imagery proficiency.