Topological Re-Organisation of the Brain Connectivity During Olfactory Adaptation - an EEG Functional Connectome Study

Perception of olfactory stimuli involves complex brain processing which can be directly associated with cognition and emotion. Neural structures embedded deep within the brain and several cortical entities collaborate for the processing of this unique sensory modality. In this study, we investigate the dynamic changes in the neural responses associated with prolonged and repeated exposure to pleasant odor stimuli. Graph metrics computed from EEG functional connectivity like clustering coefficient (p = 0.0008), characteristic path length (p = 0.014) and local efficiency (p = 0.0005) were seen to undergo statistically significant changes, indicating inhibition in the global and local information processing that can be attributed to olfactory adaptation. Moreover, dominant but diminishing activity was observed in the left cerebral hemisphere, signifying recruitment of various neuronal ensembles associated with complex cognitive processes for perception of pleasant odor stimuli.

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