The talk will provide examples of use of MRI in humans to monitor effects of neuromodulation (using feedback or brain stimulation). This can be used to provide insights into healthy brain function and also to develop novel interventions for use in neurological or neuropsychiatric disorders.
MRI of neuromodulation: examples from brain stimulation and neurofeedback
Target audience: Brain imagers, including those with an interest in brain structure and function such as neuroscientists, physiologists and psychologists. Individuals with an interest in developing and applying novel therapeutic interventions in brain disorders, including psychologists, neurologists and psychiatrist, Finally, those with interests in developing new methods to monitor neuromodulation, such as MR physicists and image analysts
Outcome/objectives: Attendees will learn examples of how to MRI to monitor effects of neuromodulation interventions including brain stimulation and neurofeedback.
Purpose: The talk will provide examples of use of MRI in humans to monitor effects of neuromodulation (using feedback or brain stimulation). This can be used to provide insights into healthy brain function and also to develop novel interventions for use in neurological or neuropsychiatric disorders.
Methods: The focus will be on assessing neuromodulation using MRI. Neuromodulation examples will include brain stimulation and neurofeedback. MRI neurofeedback signals can reflect different features of the imaging signal such as amplitude of task-related activity in a single brain region, strength of functional connectivity between two regions, or classification accuracy between two stimulus types within a region of interest. Neuromodulation can also be achieved through non-invasive brain stimulation methods such as transcranial magnetic stimulation or transcranial direct current stimulation. Other MRI methods (task FMRI, resting FMRI, structural MRI), as well as behavioural measures, can be used to assess the effects of neuromodulation.
Results: Example results from real time FMRI neurofeedback will demonstrate that healthy people can effectively use this feedback signal to modulate their brain activity and that this approach potentially has clinical utility. For example, healthy people can alter the laterality of movement-related activity in motor cortex. Examples will also be given of where neurofeedback has been applied to clinical questions. For example, a proof of principle clinical study will demonstrate that these chronic stroke patients are also able to modulate laterality of their brain activity, providing rationale for further testing to assess whether this might have clinical utility. Other examples will illustrate how imaging the effects of neurofeedback manipulations can give insights into how neurofeedback training is affecting the brain. Examples will also be given using non-invasive brain stimulation to modulate brain activity and MRI to monitor effects of this modulation. For example, transcranial direct current stimulation applied to the motor cortex alters the activity and neurochemistry of this area and speeds learning in healthy volunteers. The same approach can be used to boost rehabilitation of motor deficits after stroke. MRI suggests that effective neuromodulation increases functional recruitment of the stroke-affected motor cortex.
Discussion These examples demonstrate how brain MRI neurofeedback and non-invasive brain stimulation can be used to effectively modulate brain activity. Other MRI methods can be used to monitor effects of neuromodulation. Evidence is emerging that these neuromodulation approaches can be applied to clinical questions, for example to entrain optimal patterns of brain activity after stroke and to accelerate rehabilitation of motor deficits.