Specificity of immediate memory function associated with cerebral cortex damage

The psychometric assessment of memory presents special problems in that inferences regarding this function seem to be markedly dependent upon the conditions under which it is measured. Thus, following exposure to experience X, it is problematic whether a single statement regarding a person's ability to remember X can be made. His ability would likely be a function of the time between exposure and reinstatement (Ebbinghaus, 1913; Luh, 1922; Postman and Rau, 1957) and whether assessment involved recognition, free recall, or relearning (Luh, 1922; Postman and Rau, 1957). Beyond these, the importance of the sensory channel involved in the initial experience or in reinstatement (Thurstone, 1938, p. 86) and the nature of the content to be retained (Benton, 1945) remains relatively unexplored. All of these considerations dictate against accepting differing psychological test measures of memory as equivalent and, conversely, suggest that any generalized statements regarding memory ability should be based upon several different measures.

Postnatal organic causes of mental retardation

A study of 1137 retarded children from Western Ontario revealed 129 (11.3%) in whom retardation was first noted after a specific postnatal event. Eighty-three of these were boys. The most common cause of postnatal cerebral injury in this series was a syndrome of unknown etiology characterized by the sudden onset of fever, convulsions and coma which occurred in 45 patients. The nature of this syndrome is discussed and the necessity for early treatment emphasized. Other postnatal causes of retardation are classified according to frequency, as encephalitis, accidents, meningitis and a miscellaneous group consisting of epilepsy and tumours.

Gestational and perinatal factors in brain damage

Until relatively recently, studies in this field emphasized the physical events surrounding the transfer of the infant from the uterus to the bassinette. Current investigators are devoting much more attention to intrauterine and early neonatal environment. This is not to say that mechanical factors should be forgotten or that they are unimportant, but that there seem to be factors as yet unknown which in modern practice may make a significantly greater contribution to the problem of brain damage than does direct obstetric trauma.Genetic, developmental and infective factors have been reviewed. The interrelated factors of prematurity, anoxia, trauma and brain hemorrhage have been discussed. The contribution which traumatic obstetrics has made to the problem of brain damage can be minimized by general application of standards of obstetric care and practice which are now well established. The modern practice of obstetrics must extend its active interest far beyond the goal of a living mother and child-the future health of both must be its concern. Obstetrics must be considered as an opportunity to practise a philosophy of preventive medical care in the broadest sense.