Praxis

PRAXIS (from Greek praxis - action), the ability to perform in correct sequence a series of learned or habitual muscle contractions that lead to achieving a specific goal. For praxis to be possible, the integrity of the entire complex motor apparatus is necessary. Violation of its elementary parts (central and peripheral motor conductors, centripetal conductors regulating coordination of movements, etc.) leads to disruption of action due to developing paralysis or ataxia. But even in the complete absence of paralysis and ataxia phenomena, praxis can show profound disorders due to the loss of the ability to combine these movements into a purposeful act. In such cases, they speak of apraxia (see). Disorders of praxis of this nature are of great importance for clinical practice, as they indicate damage to specific areas of the cerebral cortex (left hemisphere) or its commissural fibers (corpus callosum) (details see Apraxia). In some cases, the violation of praxis consists in replacing one action with another or (more often) elements of one action with elements of another - the so-called 'parapraxia.'