Characterization of Short-term memory induced dynamics in functional brain networks using minimum connected components
Presenter: Sushil Chandra
Authors(s): Sushil Chandra, Kaushik, Ronnie V Daniel, Vishal Pandey, Akash K Rao, Ramsingh NegiĀ 
Organization: Institute of Nuclear Medicine and Allied Sciences, DRDO, Delhi, India
It is very vital to identify the variations in the brain activations and visualize the extent of interaction between brain areas to arrive at logical interpretations regarding neuronal dynamics during higher-order cognitive functioning. Most cognitive functions are based on interactions between neuronal assemblies distributed across different cerebral regions. Recent advances in computational neuroscience have enabled interdisciplinary researchers to address challenging problems such as identification and characterization of the cognitive functions of the brain. In this paper, we propose a graph theoretical method called the Minimum Connected Component (MCC) to detect continual changes in the dynamics related to short-term memory based functional brain networks using a 64-electrode eegoTMsports EEG system. 30 participants performed a computerized version of the Corsi-block tapping test, a standard psychological test widely used for assessing visuo-spatial short-term memory. The results clearly demonstrated that MCC-based analysis of the functional brain networks was successfully able to quantify the neuronal dynamics and changes across the scalp in response to the changes in task performance. We also obtained a significant positive correlation between the MCC-based neuronal descriptors and the task performance descriptor, clearly demonstrating the sensitivity of the MCC to subtle changes occurring in functional brain networks. We plan to extend the use of this measure in assessing the neural underpinnings of executive functions as well.