Seeping Intracranial Aneurysm Simulating Neoplasm

Dissociation of Spatial Information for Stimulus Localization and the Control of Attention

“…The observed ability of commissurotomy patients to integrate the visual halffields for the control of attention is in dramatic contrast to their inability to perform explicit interfield visual comparisons. It can be inferred that interfield comparisons depend primarily on visual cortex, since they are typically disrupted when posterior callosal section or damage disconnects visual cortex (Maspes, 1948;Gazzaniga and Freedman, 1973;Sugishita, Iwata, Toyokura, Yoshioka and Yamada, 1978;Levine and Calvanio, 1980;Sidtis et al, 1981), but not when the lesion is restricted to the anterior callosum, in which case occipital interconnections are spared (Sweet, 1941;Geschwind and Kaplan, 1962;Gordon, Bogen and Sperry, 1971;Gazzaniga, Risse, Springer, Clark and Wilson, 1975). The present data imply that, in contrast, visual information for the control of attention projects to brain structures that maintain functional bilateral visual representation following callosal section.…”

Dissociation of Spatial Information for Stimulus Localization and the Control of Attention

“…The observed ability of commissurotomy patients to integrate the visual halffields for the control of attention is in dramatic contrast to their inability to perform explicit interfield visual comparisons. It can be inferred that interfield comparisons depend primarily on visual cortex, since they are typically disrupted when posterior callosal section or damage disconnects visual cortex (Maspes, 1948;Gazzaniga and Freedman, 1973;Sugishita, Iwata, Toyokura, Yoshioka and Yamada, 1978;Levine and Calvanio, 1980;Sidtis et al, 1981), but not when the lesion is restricted to the anterior callosum, in which case occipital interconnections are spared (Sweet, 1941;Geschwind and Kaplan, 1962;Gordon, Bogen and Sperry, 1971;Gazzaniga, Risse, Springer, Clark and Wilson, 1975). The present data imply that, in contrast, visual information for the control of attention projects to brain structures that maintain functional bilateral visual representation following callosal section.…”

Unilateral Perseverationnnn

“…In contrast, the left hand appeared to be "stuck in set": After the patient drew a clock face, he was asked to write his name, but he again began to write the numbers of a clock. Sweet (1941) reported a patient who had an aneurysm of the left anterior cerebral artery that led to softening and destruction of parts of the corpus callosum. Although not discussed by Sweet, when we reviewed his report and his patient's writing sample, we saw that she perseverated when she wrote with her right hand.…”

Agenesis of the Corpus Callosum

“…A definite function for the corpus callosum was suggested by the loss of memory of topography, with visual and tactile agnosia, after the surgical division of the posterior half of the corpus callosum during the removal of a colloid cyst from the third ventricle (Trescher and Ford, 1937). Further evidence of a function was the apraxia attributed to involvement of the callosal fibres by an aneurysm abutting on the corpus callosum (Sweet, 1941).…”

Dissociation of Spatial Information for Stimulus Localization and the Control of Attention

“…The observed ability of commissurotomy patients to integrate the visual halffields for the control of attention is in dramatic contrast to their inability to perform explicit interfield visual comparisons. It can be inferred that interfield comparisons depend primarily on visual cortex, since they are typically disrupted when posterior callosal section or damage disconnects visual cortex (Maspes, 1948;Gazzaniga and Freedman, 1973;Sugishita, Iwata, Toyokura, Yoshioka and Yamada, 1978;Levine and Calvanio, 1980;Sidtis et al, 1981), but not when the lesion is restricted to the anterior callosum, in which case occipital interconnections are spared (Sweet, 1941;Geschwind and Kaplan, 1962;Gordon, Bogen and Sperry, 1971;Gazzaniga, Risse, Springer, Clark and Wilson, 1975). The present data imply that, in contrast, visual information for the control of attention projects to brain structures that maintain functional bilateral visual representation following callosal section.…”

Unilateral Perseverationnnn

“…In contrast, the left hand appeared to be "stuck in set": After the patient drew a clock face, he was asked to write his name, but he again began to write the numbers of a clock. Sweet (1941) reported a patient who had an aneurysm of the left anterior cerebral artery that led to softening and destruction of parts of the corpus callosum. Although not discussed by Sweet, when we reviewed his report and his patient's writing sample, we saw that she perseverated when she wrote with her right hand.…”

Agenesis of the Corpus Callosum

“…A definite function for the corpus callosum was suggested by the loss of memory of topography, with visual and tactile agnosia, after the surgical division of the posterior half of the corpus callosum during the removal of a colloid cyst from the third ventricle (Trescher and Ford, 1937). Further evidence of a function was the apraxia attributed to involvement of the callosal fibres by an aneurysm abutting on the corpus callosum (Sweet, 1941).…”

Dissociation of Spatial Information for Stimulus Localization and the Control of Attention

“…The observed ability of commissurotomy patients to integrate the visual halffields for the control of attention is in dramatic contrast to their inability to perform explicit interfield visual comparisons. It can be inferred that interfield comparisons depend primarily on visual cortex, since they are typically disrupted when posterior callosal section or damage disconnects visual cortex (Maspes, 1948;Gazzaniga and Freedman, 1973;Sugishita, Iwata, Toyokura, Yoshioka and Yamada, 1978;Levine and Calvanio, 1980;Sidtis et al, 1981), but not when the lesion is restricted to the anterior callosum, in which case occipital interconnections are spared (Sweet, 1941;Geschwind and Kaplan, 1962;Gordon, Bogen and Sperry, 1971;Gazzaniga, Risse, Springer, Clark and Wilson, 1975). The present data imply that, in contrast, visual information for the control of attention projects to brain structures that maintain functional bilateral visual representation following callosal section.…”

Unilateral Perseverationnnn

“…In contrast, the left hand appeared to be "stuck in set": After the patient drew a clock face, he was asked to write his name, but he again began to write the numbers of a clock. Sweet (1941) reported a patient who had an aneurysm of the left anterior cerebral artery that led to softening and destruction of parts of the corpus callosum. Although not discussed by Sweet, when we reviewed his report and his patient's writing sample, we saw that she perseverated when she wrote with her right hand.…”

Agenesis of the Corpus Callosum

“…A definite function for the corpus callosum was suggested by the loss of memory of topography, with visual and tactile agnosia, after the surgical division of the posterior half of the corpus callosum during the removal of a colloid cyst from the third ventricle (Trescher and Ford, 1937). Further evidence of a function was the apraxia attributed to involvement of the callosal fibres by an aneurysm abutting on the corpus callosum (Sweet, 1941).…”