Cross-species cortical alignment identifies different types of anatomical reorganization in the primate temporal lobe.
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ABSTRACT:
SUBMITTER: Eichert N
PROVIDER: S-EPMC7180052 | biostudies-literature | 2020 Mar
REPOSITORIES: biostudies-literature
Publications
Cross-species cortical alignment identifies different types of anatomical reorganization in the primate temporal lobe.
Eichert Nicole N Robinson Emma C EC Bryant Katherine L KL Jbabdi Saad S Jenkinson Mark M Li Longchuan L Krug Kristine K Watkins Kate E KE Mars Rogier B RB
eLife 20200323
Evolutionary adaptations of temporo-parietal cortex are considered to be a critical specialization of the human brain. Cortical adaptations, however, can affect different aspects of brain architecture, including local expansion of the cortical sheet or changes in connectivity between cortical areas. We distinguish different types of changes in brain architecture using a computational neuroanatomy approach. We investigate the extent to which between-species alignment, based on cortical myelin, ca ...[more]
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Project description:BackgroundFunctional MRI was used to study the impact of temporal lobe epilepsy (TLE) and anterior temporal lobectomy (ATL) on the cortical language network in patients with medically refractory TLE.MethodsNineteen patients with medically refractory TLE and 11 healthy control subjects were enrolled in this study. Ten patients underwent left ATL (mean age 35.2 +/- 3.8 years), and 9 underwent right ATL (mean age 35.9 +/- 2.6 years). The subjects silently generated verbs in response to a series of visually presented nouns inside the scanner. Correlation analysis was performed between the subjects' performance on the clinical language tests and their neural response in the a priori cortical regions.ResultsPreoperative data revealed that the patients with TLE showed increased neural activity in the right inferior frontal gyri (IFG) and middle frontal gyri (MFG). The right TLE patients demonstrated strong correlation between their language performance and the level of cortical activation within the typical language areas. However, such a correlation was absent in the left TLE patients. After the ATL surgery, the left TLE patients showed reduced activation in the left MFG and right IFG, whereas no difference was observed in the right TLE patients. In the right TLE patients, the correlation between language performance and neural response shifted from the typical language areas to the anterior cingulate cortex.ConclusionThis study demonstrates that the cortical language network is affected differently by the left and right temporal lobe epilepsy and is reorganized after anterior temporal lobectomy.
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