Visual Perception and Visuospatial Functions

The FORAMENRehab® Visual Perception and Visuospatial Functions module is designed for the cognitive remediation of disorders in visual perception and visuospatial functions.

The prerequisites for visual perception and recognition are the functions of the eye, muscles that move the eye, optic tract, as well as the visual cortex. Especially lesions in the temporal, occipital and parietal lobes of the right hemisphere lead to diverse neuropsychological disturbances in visual perception.

The recognition process of visual perception starts on the cortex by the analysis of simple characteristics such as angles, colors and contrasts. After the discrimination of these characteristics the shape (gestalt) starts to form a tree-dimensional entity, which is finally recognized according to the knowledge stored in the memory. Visual agnosia means that the patient can see but does not recognize what he sees. The difficulty in recognition may have to do with pictorial material as well as concrete objects. The visual agnosias are traditionally classified into two major categories: associative agnosias arising from a breakdown in one or more aspects of the patient’s information store or generic knowledge and apperceptive agnosias due to higher level perceptual disturbances. The specific content of an agnosic disorder depends on individual variations in the specific functions involved in the lesion site. The special forms of agnosias are also difficulties in recognizing and differentiating faces as well as colors.

The visuospatial functions mean the ability to understand visual representations and their spatial relationships. The term “spatial” refers to perceiving space, distances, and directions.

Constructional performance combines perceptual activity with motor response and always has a spatial component. Patients with constructional disturbances tend to take a piecemeal, fragmented approach, losing the overall gestalt of the construction task.

The visual inattention phenomenon also called visual neglect involves absence of awareness of visual stimuli in the field of vision, which is contralateral to the lesion.

Recommended literature:

Humphreys, G.W. (edit.). (2001).
Case studies in neuropsychology of vision.
Hove: Psychology Press

Kaipio, M-L., Sarajuuri, J., Koskinen, S. (2000).
The INSURE program and modifications in Finland.
In: International handbook of neuropsychological rehabilitation.
New York: Kluwer Academic/Plenum Publishers. p247-258

Lezak, M.D. (1995).
Neuropsychological assessment.
Oxford: Oxford University Press.

Prigatano, G.P. (1999).
Principles of neuropsychological rehabilitation.
New York: Oxford University Press.

Robertson, I.H., Halligan, P. (1999).
Spatial neglect. A clinical handbook for diagnosis and treatment.
Hove: Psychology Press.

Stuss, D.T., Winocur, G., Robertson, I.H. (edit.). (1999).
Cognitive neurorehabilitation.
Cambridge: Cambridge University Press.

Wood, L., Fussey, I. (edit.). (1990)
Cognitive rehabilitation in perspective.
London: Taylor & Francis

Zihl, J. (2000).
Rehabilitation of visual disorders after brain injury.
Hove: Psychology Press.