Choa, Fow-SenRoopan, Roopan2021-09-012021-09-012020-01-0112221http://hdl.handle.net/11603/22916This study evaluates brain state activation differences in old vs the young individuals using energy-landscape analysis based on the resting-state fMRI data. The aim is to study brain Intra- and inter-network interaction differences between two age group subjects with a large age gap between them. The first-order interactions, based on a binary quantization approximation, among different brain networks such as Default Mode Network, Frontoparietal Network, Sensorimotor Network, Salience Network, Attention Network, Visual Network, and Auditory Network were evaluated. Disconnectivity graphs and activation maps of brain states were produced, which help to indicate the correlation and anti-correlation of these networks. The findings suggest that the old brains contain more nested structures both in their intra-and internetwork activity patterns compared with those of the young brains. For inter-network interactions, the Salience network, Auditory network, and Attention network are active and inactive together in both the old and young brains, implying a general correlation among them. The Visual network and Frontoparietal network are anti-correlated for both old and young brains. Furthermore, the old brains distinguish themselves from the young brains, showing special brain connectivity, which was not found in young brains? activity maps, that is they can turn on both DMN and ATN together and shut off the visual and sensory-motor networks. Such a brain state may represent the ability to allow a person'sinternal model, DMN, dominating the imagination or brain working-memory manipulation. A state of deeper mind or deeper thought without external interruptions.application:pdfBoltzmann fittingEnergy Landscapefunctional magnetic resonance imagingIsing modelstatistical physicsText