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H L Teuber

Publications and source records attributed to H L Teuber.

At least 19 recordsLinked to original sources

Changing patterns of childhood aphasia.

Acquired aphasia in children has been generally characterized as nonfluent, transient, and frequently due to right hemisphere lesions. We studied 65 children with unilateral hemispheric brain lesions occurring after speech acquisition any time from the second through the fourteenth year. Of 34 patients with a left hemisphere lesion, 25 had an initial aphasic speech disturbance, while of 31 patients with a right hemisphere lesion, only 4 (including 2 left-handers) showed any initial aphasia. All those who became aphasic before the age of 8 years eventually regained speech, but recovery time required ranged from less than a month to more than two years. One 5-year-old boy who recovered had initial jargon aphasia. Our review of the literature indicated that the conflict between our results and the traditional claim of frequent aphasia with right hemisphere lesions only apparent; the great majority of crossed aphasias are concentrated in reports written before antibiotics were used, and many cases were assoicated with systemic bacterial infections.

Adolescent↗

Mirror movements after childhood hemiparesis.

Mirror movements are normal in childhood and may persist to a later age following early brain lesions. We studied these movements in patients with childhood hemiparesis at different ages. The earlier the lesions, the more the mirror movements persisted. More mirror movement persisted in the nonparetic hand than in the paretic one. Complete paralysis of either hand tended to abolish all mirror movements in both hands. The task eliciting the most mirror movement was one that may come under ipsilateral control following contralateral damage. The greater persistence of mirror movements after earlier lesions appears to be an indicator of more extensive compensatory motor system reorganization that takes place after damage to a less mature nervous system.

Adolescent↗

Recovery of function after brain injury in man.

Late after-effects of cerebral trauma are difficult to study because patients tend to be seen for persisting symptoms, and not simply for their lesions. We have tried to avoid this bias by recalling periodically, over the years, 520 men with known brain injuries incurred in World War II or in Korea or Vietnam. These men are seen irrespective of clinical need and all undergo intensive behavioural and neurological assessment, which still continues. For such groups, recovery is impressive, though one third shows persistent intellectual loss. In addition, some tasks reveal specific deficits enduring unchanged, after th first 2-3 yr, for the 20-30 yr of follow-up (e.g. visual field defects, certain auditory discrimination losses, trouble on various complex perceptual tasks). These lasting deficits are linked to the site and size of focal injury, often representing remnants of more severe initially-present disorders. The extent of recovery is correlated with age at the time of trauma, the youngest faring best. Extension of such studies to cases of early brain damage (birth to five years), as indicated by hemiparesis, shows the familiar 'escape' of language after early left-hemisphere lesions but this is achieved at a price, the price being borne by non-verbal functions that normally depend on the integrity of the right hemisphere.

Age Factors↗

Unity and diversity of frontal lobe functions.

In attempting to summarize recent work on functions of granular prefrontal cortex in primates, including man, and possible homologues of these structures in rodents and carnivores, four question need to be asked, the questions of 'where', 'when', 'what' and 'how'. Progress since the Pennsylvania Symposium has been considerable for questions of 'where' and 'when': localization of symptoms ('where') fields a double gradient (up-down and back-to-front) in monkeys, and a right-left difference in man; analysis of time factors ('when') distinguishes early and late lesions, single and serial removals, or succeeds in recording and stimulating at critical moments during performance. However, problems of 'what' and 'how' are still largely unsolved: we do not yet know what various prefrontal symptoms sigify, in terms of normal function, and are only beginning to see how individual prefrontal neurons act and interact. Advances on these questions are likely if one exploits an extended version of those hypotheses about prefrontal physiology that attribute to these structures neither purely sensory nor purely motor functions but consider them instead as sources of 'corollary discharges' whereby the organism presets its sensory systems for the anticipated consequences of its own action.

Animals↗