Effects of Central Vision, Peripheral Vision, and Haptic Inputs on Complex Verbal and Spatial Tasks

Abstract

The aim of the present study is to investigate how quite specific sensory inputs (visual inputs from central or peripheral regions of the retina and haptic inputs) relate to complex cognitive performance. We compare individuals with severe peripheral visual field loss, Braille reader with central scotomata (SDB group), print readers with central scotomata, and normally sighted people on visual reading and spatial imagery tasks. Experiment 1 showed that the SDB subjects were significantly less accurate than the other groups on reading visual print letters, words, digits, and 4-digit numbers aloud. In experiment 2, SDB subjects also performed worse than the other subjects on imagery tasks that required indicating spatial characteristics of orally presented print letters, rotated capital letters, print words, and number shapes. Experiment 3 revealed that the SDB group improved their performance when instructed to draw the outlines of imagined stimuli shapes haptically. The findings suggest that visual memory needs perceptual practice to be maintained and that haptic inputs can be used to improve verbal and spatial imagery skills in visually impaired individuals.