Illusions

Perceptual set

A temporary readiness to perceive certain objects or events rather than other

Varies by person

Psychological factors of perceptual set

Expectations

Context

Emotions

Motivation

Illusory motion

Apparent motion

Induced motion

Motion aftereffects

Depth and size illusions

Muller-Lyer illusion

Ponzo illusion

Ames room illusion

Rubber hand experiment

Cutaneous senses + vision —> illusion of vision + touch/pain

Contrast illusion

A class of visual illusions in which the degree of a stimulus attribute (like perceived size, color, brightness) is affected by the presence of additional stimuli that differ in the same attribute

Ebbinghaus illusion

Illusion of relative size

Orange circles are the same size, but the nearby blue circles influence our perception of relative size

Visual Prostheses

Technology to help restore visual perception in individuals with vision loss or low vision

Argus II Retinal Prosthesis System: Who?

Individuals with no vision or near no vision due to retinitis pigmentosa

Argus II Retinal Prosthesis System: How?

Surgical placement of small device on the patients retina

Patient would wear a camera on glasses the processed and sent wireless info to the device

Implant stimulates cells in the retina

Retinal implants

In the eye

Cortical implants

In or on the brain

Orion Visual Cortical Prosthesis System

Stimulate visual cortex

Conducting feasibility studes

Challenges of visual prostheses

• Size and density of electrodes

• Biocompatibility of equipment

• Mechanical stability

• Complexity of human visual system —> devices are behind auditory processes for quality of restoration

• Different causes for disruption to visual perception

• Cost