Figure-Eight Coils for Magnetic Stimulation: From Focal Stimulation to Deep Stimulation

This article reviews the evolution and recent developments of transcranial magnetic brain stimulation using figure-eight coils to stimulate localized areas in the human brain. Geometric variations of figure-eight coils and their characteristics are reviewed and discussed for applications in neuroscience and medicine. Recent topics of figure-eight coils, such as focality of figure-eight coils, tradeoff between depth and focality, and approaches for extending depth, are discussed.

The Effect of Sub-Concussive Impacts during a Rugby Tackling Drill on Brain Function

Concussion is known to detrimentally affect brain health. Rugby tackles commonly occur with high collision force between tackler and ball carrier, and low impact head contact is not uncommon. Cognitive deficits following a bout of soccer ball heading has been attributed to the impact and termed sub-concussion. Although soccer ball heading studies provide evidence for acute effects of sub-concussion, it is unknown whether this phenomenon occurs following rugby tackles. This study investigates the acute effects of rugby tackles on brain function and balance in rugby players. Twenty-six volunteers were assigned to either the ball carrier (9), tackler (9) or control (8) group. Controls performed running without the tackle. Outcome measures included corticomotor function using transcranial magnetic brain stimulation (TMS) and balance was assessed by a series of tasks performed on a NeuroCom Balance Master before and immediately after a tackle training drill. Following the tackling bout, the cortical silent period (cSP) increased for the tacklers with no change for ball carrier and control groups, and no differences between groups for balance measures were observed. Lengthening of cSP observed in the tacklers following the bout has been reported in studies of concussion and may indicate long term detrimental effects.

The Future of Addiction and Recovery Healing Arts

This chapter peers into the future of addiction treatment. It begins with an exploration of repetitive transcranial magnetic brain stimulation or rTMS as a treatment for SUD. The evidence and clinical data is reviewed. Findings include outcome data on the use of rTMS. Furthermore, important brain regions central to the development of SUD are examined: the ventral tegmental area and ventral striatum appear to play a central role in the binge/intoxication stage, the extended amygdala in the withdrawal/negative affect stage, and the orbitofrontal cortex-dorsal striatum, prefrontal cortex, basolateral amygdala, hippocampus, and insula in craving. The role of genomics and gene-wide associations to deliver future personalized addiction treatments is discussed as is advanced functional neural imaging. Technology for patients and consumers, including relapse prevention apps and bidirectional biometric reading is mentioned. Breakthroughs in addiction immunology, both generalized and substance specific, are discussed as potential points of future study and interventions.

The Role of Right Prefrontal and Medial Cortex in Response Inhibition: Interfering with Action Restraint and Action Cancellation Using Transcranial Magnetic Brain Stimulation

The ability of inhibiting impulsive urges is paramount for human behavior. Such successful response inhibition has consistently been associated with activity in pFC. The current study aims to unravel the differential involvement of different areas within right pFC for successful action restraint versus action cancellation. These two conceptually different aspects of action inhibition were measured with a go/no-go task (action restraint) and a stop signal task (action cancellation). Localization of relevant prefrontal activation was based on fMRI data. Significant task-related activation during successful action restraint was localized for each participant individually in right anterior insula (rAI), right superior frontal gyrus, and pre-SMA. Activation during successful action cancellation was localized in rAI, right middle frontal gyrus, and pre-SMA. Subsequently, fMRI-guided continuous thetaburst stimulation was applied to these regions. Results showed that the disruption of neural activity in rAI reduced both the ability to restrain (go/no-go) and cancel (stop signal) responses. In contrast, continuous thetaburst stimulation-induced disruption of the right superior frontal gyrus specifically impaired the ability to restrain from responding (go/no-go), while leaving the ability for action cancellation largely intact. Stimulation applied to right middle frontal gyrus and pre-SMA did not affect inhibitory processing in neither of the two tasks. These findings provide a more comprehensive perspective on the role of pFC in inhibition and cognitive control. The results emphasize the role of inferior frontal regions for global inhibition, whereas superior frontal regions seem to be specifically relevant for successful action restraint.