Relationship between primitive reflexes, extra-pyramidal signs, reflective apraxia and severity of cognitive impairment in dementia of the Alzheimer type.

Controversy exists in the literature about the significance of primitive reflexes (PR) and extrapyramidal signs (EP) as diffuse cortical dysfunction signs and their relationship to age and cognitive impairment. A sample of 91 patients with a dementia of the Alzheimer type were examined with a standardized technique to assess the relationship between the finding of PR, EP and severity of cognitive impairment measured by Mini-Mental Status Examination. The value of a short cognitive test, the reflective apraxia (i.e. imitation of meaningless gestures), were also assessed. A significantly lower MMS score was correlated with the number of present PR and with presence of snout, sucking and grasping reflexes. No correlation was found between presence or absence of PR and age, depression, or drug therapy. EP score was correlated with the number of present PR and MMS, but not with age. Reflective apraxia score was significantly correlated with the degree of cognitive impairment and was found with lower cognitive impairment than PR.