Showing papers on "Corpus callosum published in 1971"

Reply to McKeever and Huling

Abstract: The brief articles appearing in Psychonomic Science cannot possibly contain a full discussion or review of each subject introduced. In the present case the suggested addition would have left other dimensions of the problem uncovered. For those who do not know the history, it is as follows. Up until the mid-50s, the majority view in psychobiology was that the corpus callosum played little or no important role in integrating sensory or motor information across the cerebral hemispheres. This was in large part due to the seemingly exhaustive studies of Akelaitis (1941, 1943, 1944, 1942) at the University of Rochester who studied some 26 cases of partial and complete callosal section. His inability to demonstrate any reliable deficits undercut dozens of earlier studies—Poffenberger’s (1912) being but one. Lashley, after reviewing the literature at the time commented that the corpus callosum’s only function seemed to be to hold the cerebral hemispheres together.

The neuroanatomical changes associated with dilated corpus callosal and distended ambiens cisterns

Abstract: At pneumoencephalography, lack of easy ventricular filling and enlargement of the cisterns of the corpus callosum, ambiens and interpositum are seen most often in patients with obstructive hydrocephalus. A suggested explanation for the widening of these cisterns is that as the lateral ventricles distend, the brain over the ventricles is compressed and displaced outward and upward. The falx prevents elevation of the central portion of the corpus callosum. Elevation of the brain substance, and particularly of the cingulate gyrus, opens the cistern of the corpus callosum on either side of the falx. Gas in the wide callosal cistern, and in the cingulate sulcus, have a “V” shape because the lateral margins of the corpus callosum are elevated by the distended lateral ventricles and the central portion held down by the falx. Distension of the posterior part of the ambiens cisterns occurs most often in patients with posterior fossa mass lesions and upward transtentorial herniation. In such patients the b...

Orbicularis Oris-Tiefenreflex (Mundreflex), seine semiologische Bedeutung bei cerebralen Läsionen — Lokalisationsversuch

Abstract: The authors have studied the lip reflex in patients with cerebral lesions, calling the reflex “Orbicularis Oris Deep Reflex” (O.O.D.R.). The methods used in this study are described. The reflex was absent in 2,000 (two thousand) normal subjects. In 68 cases the O.O.D.R., more or less accentuated, was found to be associated with the following conditions: Frontal gliomas (15 cases), frontal corpus callosum gliomas (7 cases), meningiomas of the anterior region (7 cases), intracranial hematomas (11 cases), aneurysms of the cerebral anterior artery, the communicating anterior and the pericallosal artery (6 cases), cerebral atrophy (7 cases), encephalopathies (3 cases), tumors of the third ventricle (3 cases), and frontal metastases (3 cases). In general, in cases of marked O.O.D.R. the authors often found concomitant behavioral disturbances, sometimes of the confusional type; akinetic mutism (6 cases) or Korsakoff's syndrome (4 cases) were less frequently observed. This reflex was also often associated with extrapyramidal disturbances and exaggeration of the other median reflexes. The EEG shows slow bifrontal anomalies or temporal anomalies extending to the frontal area, or anomalies of diffuse distribution. The analysis of the results confirms the importance of the frontal bilateral lesions and especially of the antero-medio-basal lesions in giving rise to this archaic reflex. The mechanism of its production is still hypothetic and therefore a matter of discussion.