(JHBI TS/第10回) 2022年8月23日(火)15:00

スケジュール

15:00 - 15:05 Opening Remarks and announcements 
15:05 - 15:20

Talk 1: Marino Kawamoto 

 (Chair:Akiko Uematsu)

15:20 - 15:35

Talk 2:Takumi Mitsuhashi 
(Chair: Akiko Uematsu)

15:35 - 16:20

Lecture:Stephanie Forkel (Donders Research Institute)

(Chair: Ryuta Aoki)

16:20 - 

Free discussion between speakers and attendees

Open Discussion 

 

講演者

Talk 1:  Marino Kawamoto 
Tokyo Medical and Dental University/Tamagawa University

Parental rejection in childhood is related to smaller hippocampal volume and low social cognitive abilities in healthy adults.

Childhood abuse reduces the hippocampus and amygdala volumes, and impairs social cognition, such as ability to recognize facial expressions. However, these associations have been studied primarily in individuals with a history of severe abuse and psychiatric symptoms, and thus, it is unclear whether it is also observed in healthy adults. We analyzed a dataset of 409 healthy adults collected at Tamagawa University. Parental rejection reflecting childhood abuse was assessed with the short form of Egna Minnen av Barndoms Uppfostran (s-EMBU), and social cognition was assessed with “Fake Smile Detection Task (FSDT)”. The hippocampus and amygdala volumes were extracted from T1-weighted MRI data using FreeSurfer. We found that greater parental rejection resulted in smaller hippocampal and amygdala volumes and lower performance on the FSDT. Hippocampal volume mediated the effect of maternal rejection on performance on the FSDT. These findings are in line with the facts that structural and functional connectivity is found between the hippocampus and amygdala, and that these brain regions jointly involve in social cognition. Our results suggest that parental rejection may affect hippocampal and amygdala volumes and social cognitive function even in adults without apparent psychiatric symptoms. 

 

Talk 2:  Takumi Mitsuhashi
Juntendo University

Dynamic tractography-based localization of spike sources and animation of spike

Intracranially-recorded spike discharges are suggested to have clinical utility. Previous intracranial electroencephalography (iEEG) studies reported that resection of electrode sites generating spikes frequently or those preceding others was predictive of successful seizure control. However, one cannot completely rule out the possibility that the true spike generator may have been unsampled by intracranial electrodes. In the present study of mono-synaptic spike propagations in patients with drug-resistant temporal lobe epilepsy (TLE), we identified the events of interictal spikes that propagated to other regions on iEEG recording and had a supporting white matter tract on diffusion-weighted imaging tractography. We estimated the source/origin of spike discharges using the tractography-based streamline length of white matter tracts from intracranial electrode sites and observed spike latencies at given sites. We then built a movie, named “dynamic tractography”, animating the spike propagating from the estimated source through the white matter. As result, the estimated spike sources in medial TLE patients with good seizure outcomes were more likely to be in the resected area and in the medial temporal lobe region than those associated with poor outcomes. The dynamic tractography successfully animated spike propagations.

 

Lecture:  Stephanie Forkel
Donders Research Institute for Brain, Cognition and Behaviour 

Anatomical variability in cognitive and clinical neuroscience

A large amount of variability exists across human brains; revealed initially on a small scale by postmortem studies and, more recently, on a larger scale with the advent of neuroimaging. Here we compared structural variability between human and macaque monkey brains using grey and white matter magnetic resonance imaging measures. The monkey brain was overall structurally as variable as the human brain, but variability had a distinct distribution pattern, with some key areas showing high variability. We also report the first evidence of a relationship between anatomical variability and evolutionary expansion in the primate brain. This suggests a relationship between variability and stability, where areas of low variability may have evolved less recently and have more stability, while areas of high variability may have evolved more recently and be less similar across individuals. We showed specific differences between the species in key areas, including the amount of hemispheric asymmetry in variability, which was left-lateralized in the human brain across several phylogenetically recent regions. This suggests that cerebral variability may be another useful measure for comparison between species and may add another dimension to our understanding of evolutionary mechanisms.