Dendritic organization of the anterior speech area

Scheibel, Arnold B.; Paul, Linda; Fried, Itzhak; Forsythe, Alan B.; Tomiyasu, Uwamie; Wechsler, Adam F.; Kao, Albert; Slotnick, J.

doi:10.1016/0014-4886(85)90137-2

Cited by 205 publications

(48 citation statements)

References 16 publications

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“…In humans, however, only preliminary investigations with limited sample sizes have explored such regional variation. One series of studies documented greater dendritic complexity in the classical language regions of Broca and Wernicke than in sensorimotor cortices (Scheibel et al, 1985;Simonds and Scheibel, 1989;Jacobs et al, 1993a). Another pioneering investigation found that dendritic profiles in different cortical regions roughly reflected the computational tasks performed by those areas: dendritic arbors in two association cortices (areas 9 and 39) and in the finger region of the primary sensory strip were typically more complex than in the corresponding thoracic region (Scheibel et al, 1990).…”

Section: Regional Differences In Dendritic Systemsmentioning

confidence: 96%

Life-span dendritic and spine changes in areas 10 and 18 of human cortex: A quantitative golgi study

Jacobs

Driscoll

Schall³

1997

J. Comp. Neurol.

369

246

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Dendritic neuropil is a sensitive indicator of the aging process and may exhibit regional cortical variations. The present study examined regional differences and age-related changes in the basilar dendrites/spines of supragranular pyramidal cells in human prefrontal (area 10) and secondary occipital (area 18) cortices. Tissue was obtained from the left hemisphere of 26 neurologically normal individuals ranging in age from 14 to 106 years (M(age) = 57 +/- 22 years; 13 males, 13 females). In tissue prepared by a modified rapid Golgi technique, ten neurons were sampled from each cortical region (N = 520) and were evaluated according to the following parameters: total dendritic length, mean segment length, dendritic segment count, dendritic spine number, and dendritic spine density. The effects of age and Brodmann areas were analyzed with a nested multiple analysis of variance design. Despite considerable interindividual variation, several clear findings emerged: 1) Dendritic systems were significantly larger in area 10 than in area 18 across the sampled life span, presumably because of the more integrative function of area 10 neurons. 2) There was a significant age effect, with a substantial decline in dendritic neuropil from the younger (< or =50 years) group to the older (>50 years) group, especially in spine measures, which decreased almost 50%. 3) Dendritic values were relatively stable after 40 years of age, suggesting that dendritic/spine degeneration in older, relatively healthy individuals may not be an inevitable consequence of the aging process. These findings underscore the importance of life-long commitment to a cognitively invigorating environment.

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Section: Regional Differences In Dendritic Systemsmentioning

confidence: 96%

Life-span dendritic and spine changes in areas 10 and 18 of human cortex: A quantitative golgi study

Jacobs

Driscoll

Schall³

1997

J. Comp. Neurol.

369

246

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“…Lateralized differences in, for example, neuronal number and connectivity (e.g. [25,26,61]) as well as in neurotransmitter distribution and sensitivity to hormones (e.g. [42,65]) then cause these sensory inputs to be analyzed somewhat differently in the two hemispheres.…”

Section: Introductionmentioning

confidence: 99%

Picture the difference: electrophysiological investigations of picture processing in the two cerebral hemispheres

2002

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The nature of semantic memory and the role of the two cerebral hemispheres in meaning processing were examined using event-related brain potentials (ERPs) elicited by pictures in sentences. Participants read sentence pairs ending with the lateralized presentation of three target types: (1) expected pictures, (2) unexpected pictures from the expected semantic category, and (3) unexpected pictures from an unexpected category. ERPs to contextually unexpected pictures were more negative 350-500 ms (larger N400s) than those to expected pictures in both visual fields. However, while N400s to the two types of unexpected items did not differ with left visual field presentations, they were smaller to the unexpected items from the expected category with right visual field presentations. This pattern, previously observed to words [Brain Language 62 (1998) 149], suggests general differences in how the two hemispheres use context on-line. Other aspects of the N400 response-and effects on earlier ERP components-reveal differences between pictures and words, suggesting that semantic memory access is not modality-independent. The P2 component varied with ending type for right but not left visual field presentations, suggesting that the left hemisphere may use contextual information to prepare for the visual analysis of upcoming stimuli. Furthermore, there was clear evidence for an earlier negativity ("N300"), which varied with ending type but, unlike the N400, was unaffected by visual field of presentation. Overall, the results support our hypothesis that the left hemisphere actively uses top-down information to preactivate perceptual and semantic features of upcoming stimuli, while the right hemisphere adopts a "wait and see" integrative approach.

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“…Brodmann's areas 44 and 45 (Brodmann 1909), are of considerable interest in functional imaging studies of language. It is a long-standing matter of discussion whether or not anatomical features are associated with the functional lateralization of speech (Galaburda 1980;Hayes & Lewis 1995Jacobs et al 1993;Simonds & Scheibel 1989;Scheibel et al 1985). Furthermore, the precise position and extent of both areas in stereotaxic space and their inter-subject variability still remain to be analysed, since Brodmann's delineation is highly schematic, not documented in su¤cient detail and does not contain any statement about inter-subject variability.…”

Section: (B) Post-mortem Cryosectioned Materials (I) Data Acquisitionmentioning

confidence: 99%

A probabilistic atlas and reference system for the human brain: International Consortium for Brain Mapping (ICBM)

Mazziotta

Toga²,

Evans

et al. 2001

Phil. Trans. R. Soc. Lond. B

2,325

1,753

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Motivated by the vast amount of information that is rapidly accumulating about the human brain in digital form, we embarked upon a program in 1992 to develop a four-dimensional probabilistic atlas and reference system for the human brain. Through an International Consortium for Brain Mapping (ICBM) a dataset is being collected that includes 7000 subjects between the ages of eighteen and ninety years and including 342 mono-and dizygotic twins. Data on each subject includes detailed demographic, clinical, behavioural and imaging information. DNA has been collected for genotyping from 5800 subjects. A component of the programme uses post-mortem tissue to determine the probabilistic distribution of microscopic cyto-and chemoarchitectural regions in the human brain. This, combined with macroscopic information about structure and function derived from subjects in vivo, provides the ¢rst large scale opportunity to gain meaningful insights into the concordance or discordance in micro-and macroscopic structure and function. The philosophy, strategy, algorithm development, data acquisition techniques and validation methods are described in this report along with database structures. Examples of results are described for the normal adult human brain as well as examples in patients with Alzheimer's disease and multiple sclerosis. The ability to quantify the variance of the human brain as a function of age in a large population of subjects for whom data is also available about their genetic composition and behaviour will allow for the ¢rst assessment of cerebral genotype^phenotype^behavioural correlations in humans to take place in a population this large. This approach and its application should provide new insights and opportunities for investigators interested in basic neuroscience, clinical diagnostics and the evaluation of neuropsychiatric disorders in patients.

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Dendritic organization of the anterior speech area

Cited by 205 publications

References 16 publications

Life-span dendritic and spine changes in areas 10 and 18 of human cortex: A quantitative golgi study

Life-span dendritic and spine changes in areas 10 and 18 of human cortex: A quantitative golgi study

Picture the difference: electrophysiological investigations of picture processing in the two cerebral hemispheres

A probabilistic atlas and reference system for the human brain: International Consortium for Brain Mapping (ICBM)

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