Reciprocal or independent hemispheric specializations: Evidence from cerebral dominance for fluency, faces, and bodies in right- and left-handers.

This study examined contrasting patterns of psycholinguistic functioning among normal children and children with reading disabilities. In general, results suggested that children with reading disabilities had significantly different patterns of psycholinguistic functioning in auditory vocal, visual motor, vocal encoding, and motor encoding activities.

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Dichotic words listening test: technical aspects and results in normal right-handed individuals

Arquivos de Neuro-Psiquiatria ◽

10.1590/s0004-282x1994000200009 ◽

1994 ◽

Vol 52 (2) ◽

pp. 204-209 ◽

Cited By ~ 4

Author(s):

Ana Regina Caner-Cukiert ◽

Arthur Cukiert

Keyword(s):

Cerebral Dominance ◽

Listening Test ◽

Left Handed ◽

Listening Tests ◽

Msec Interval ◽

Normal Individuals ◽

Hemisphere Dominance ◽

Four Blocks ◽

Right Ear Advantage ◽

The Right

Dichotic listening tests have been being used in an increasing frequency to determine in a non-invasive way the cerebral dominance in right- and left-handed patients. This is especially relevant when surgery in eloquent brain areas is being contemplated. A Portuguese version of the dichotic words listening test was developed based mainly on Wexler's protocol. It consisted of 15 pairs of words with a stimulus dominance lower than 50%. They were recorded using natural voice and time and intensity synchronization by means of a specialized software. Each pair of words was presented twice in different channels within each block. The items were randomized and presented with a 300 msec interval between each trial. Four blocks of 30 pairs of words each were created, totalizing 120 trials. In the scoring process, the words heard over the right and left ears were wrote down. The number of times each word was heard over each ear was computed and their values subtracted yielding a partial score for each specific word pair. This process was repeated for all stimuli pair and a final score for right and left predominance was then reached. Thirty-two right handed normal individuals underwent the test 93.8% showed a right ear advantage. These results are very similar to the actual left hemisphere dominance rate in a right-handed population.

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The Continuum of Psychosis and Its Genetic Origins

The British Journal of Psychiatry ◽

10.1192/bjp.156.6.788 ◽

1990 ◽

Vol 156 (6) ◽

pp. 788-797 ◽

Cited By ~ 187

Author(s):

T. J. Crow

Keyword(s):

Sex Chromosome ◽

Homo Sapiens ◽

Polymorphic Marker ◽

Cerebral Dominance ◽

Homo Erectus ◽

Evolutionary Development ◽

Pseudoautosomal Region ◽

Sibling Pairs ◽

Homo Habilis ◽

Y Chromosomes

Attempts to draw a line of genetic demarcation between schizophrenic and affective illnesses have failed. It must be assumed that these diseases are genetically related. A post-mortem study has demonstrated that enlargement of the temporal horn of the lateral ventricle in schizophrenia but not in Alzheimer-type dementia is selective to the left side of the brain. This suggests that the gene for psychosis is the ‘cerebral dominance gene‘, the factor that determines the asymmetrical development of the human brain. That the psychosis gene is located in the pseudoautosomal region of the sex chromosomes is consistent with observations that sibling pairs with schizophrenia are more often than would be expected of the same sex and share alleles of a polymorphic marker at the short-arm telomeres of the X and Y chromosomes above chance expectation. That the cerebral dominance gene also is pseudoautosomal is suggested by the pattern of verbal and performance deficits associated with sex-chromosome aneuploidies. The psychoses may thus represent aberrations of a late evolutionary development underlying the recent and rapid increase in brain weight in the transition fromAustralopithecusthroughHomo habilisandHomo erectustoHomo sapiens.

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Responses of Stuttering and Non-Stuttering Children to a Dichotic Listening Task

Perceptual and Motor Skills ◽

10.2466/pms.1974.38.1.263 ◽

1974 ◽

Vol 38 (1) ◽

pp. 263-264 ◽

Cited By ~ 17

Author(s):

L. Gruber ◽

R. L. Powell

Keyword(s):

High School ◽

School Children ◽

Dichotic Listening ◽

Cerebral Dominance ◽

Dichotic Listening Task ◽

Listening Task

Performance on a dichotic listening task of 28 normally speaking and 28 stuttering elementary and high school children showed no significant inter-ear differences. These results do not support the idea that stuttering results from lack of cerebral dominance for speech.

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