Cognitive disorders are

C i.e. Dementia In fouh edition of Diagnostic Statistical Manual of mental Disorders (DSM - IV) , three groups of disorders - delirium, dementia, and the amnestic disorders - are characterized by primary symptoms common to all the disorders, which is an impairment in cognition (memory, language or attention.)Q In the past, these conditions were classified under the heading "organic mental" or organic brain disorders (i.e. disorders that had an identifiable pathological condition such as brain tumor, cerebrovascular disease or drug intoxication). Those disorders with no generally accepted organic basis (eg. depression) were called functional disorders. But this century old distinction has been deleted and now every psychiatric disorder has been considered to have an organic (biological or chemical) component. Cognition or higher mental functions are evaluated by testing memory, mathematics, reading, writing, visuospatial skills, constructional ability, fine sensory function (stereognosis, graphesthesia, two point discrimination), finger - gnosis, right - left orientation, executive functions and abstraction. - in Neuropsychiatric mental status examination. Mini - mental state examination (MMSE) is a screening test to evaluate cognitive stateQ of a possible 30 points, a score below 25 suggests possible impairment, and a score below 20 indicates definite impairment.