Perceptual-motor dysfunction.

PURPOSE OF REVIEW: This article highlights the importance of integrated perceptual information (motor planning, sequencing, and representation) and discusses the integration of these cognitive domains by means of feedforward and feedback loops in the successful acquisition and execution of voluntary behaviors. The article also discusses the dysfunction in the perceptual-motor process that can occur with neurologic injury, resulting in apraxias, agnosia, hemineglect, and Balint syndrome.

RECENT FINDINGS: A combination of functional imaging and lesional studies continues to refine our understanding of the role of the posterior parietal region in the integration of perception with motor action. Different disorders provide contrasting views into the nature of perceptual-motor function and its disruption. Novel rehabilitation techniques may provide improved function in the future.

SUMMARY: Studies continue to demonstrate the importance of unimodal and heteromodal association cortices, as well as the extrapyramidal system (especially the basal ganglia) in perceptual-motor functions across a wide range of activities and disease states. The nondominant hemisphere dictates where attention and intention are to be directed in space, and the dominant hemisphere provides information on how to accomplish skilled complex actions. While the role of perceptual-motor dysfunction in developmental disorders has been long considered, the role of perceptual-motor dysfunction in neurodegenerative diseases, from Parkinson disease to corticobasal syndrome to posterior cortical atrophy, is becoming more apparent. A clear need exists for more robust rehabilitation strategies in these neurodegenerative diseases.