The Role of Transcranial
Magnetic Stimulation as a Network Moderator with Precision Intrinsic System
Mapping
Cognitive control regulates thoughts and aids action selection as well as guides switching, directing, and manipulating between actions. Deficits of cognitive control have been implicated in various afflictions associated with disordered thought such as, Alzheimer’s Disease, binge eating disorder, anxiety, schizophrenia, and Parkinson’s Disease. Functional connectivity is the temporal relationship of different brain regions and can show how the brain is connected and how it communicates. Understanding functional connectivity between and within networks and their responses to perturbation is crucial to increase wellbeing of those with cognitive impairments by being able to target specific regions with deficits. Using functional magnetic resonance imaging (fMRI) data, cognitive functional networks were obtained utilizing an individualized functional brain parcellation. Transcranial magnetic stimulation (TMS) was performed at three individualized targets for each individual subject (n=20). The targets were the frontoparietal control network (FPCN) associated with task switching, the dorsal attention network (DAN) associated with alerting and integration of external attention, and the vertex which acted as a control location. All subjects participated in three sessions where intermittent theta-burst stimulation (iTBS) was administered to a different network for each session in a randomized-counterbalanced manner. The subjects completed three tasks: the Navon, the Stroop, and the n-back that test switching, inhibiting, and working memory respectively before and after stimulation. A statistical analysis using mixed-effects modeling was completed to determine the effects of TMS on behavior and to examine functional connectivity within and between the specified networks on a trial-level basis. Preliminary results show that TMS has an excitatory effect on the networks that causes an increase in associated behaviors such as faster response times and improved accuracy. Further understanding of how networks communicate with each other to bring about behavior and how they can be perturbed can allow for the creation of treatment options in those with cognitive deficits. Furthermore, through our individualized techniques, these treatment targets have shown a possibility that they can be customized to the specific person.
Cognitive control regulates thoughts and aids action selection as well as guides switching, directing, and manipulating between actions. Deficits of cognitive control have been implicated in various afflictions associated with disordered thought such as, Alzheimer’s Disease, binge eating disorder, anxiety, schizophrenia, and Parkinson’s Disease. Functional connectivity is the temporal relationship of different brain regions and can show how the brain is connected and how it communicates. Understanding functional connectivity between and within networks and their responses to perturbation is crucial to increase wellbeing of those with cognitive impairments by being able to target specific regions with deficits. Using functional magnetic resonance imaging (fMRI) data, cognitive functional networks were obtained utilizing an individualized functional brain parcellation. Transcranial magnetic stimulation (TMS) was performed at three individualized targets for each individual subject (n=20). The targets were the frontoparietal control network (FPCN) associated with task switching, the dorsal attention network (DAN) associated with alerting and integration of external attention, and the vertex which acted as a control location. All subjects participated in three sessions where intermittent theta-burst stimulation (iTBS) was administered to a different network for each session in a randomized-counterbalanced manner. The subjects completed three tasks: the Navon, the Stroop, and the n-back that test switching, inhibiting, and working memory respectively before and after stimulation. A statistical analysis using mixed-effects modeling was completed to determine the effects of TMS on behavior and to examine functional connectivity within and between the specified networks on a trial-level basis. Preliminary results show that TMS has an excitatory effect on the networks that causes an increase in associated behaviors such as faster response times and improved accuracy. Further understanding of how networks communicate with each other to bring about behavior and how they can be perturbed can allow for the creation of treatment options in those with cognitive deficits. Furthermore, through our individualized techniques, these treatment targets have shown a possibility that they can be customized to the specific person.