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Headlines 15 Dirk has also developed the New Zealand arm of BRAI3N, the Brain Research Center for Advanced, International, Innovative and Interdisciplinary Neuromodulation. Dirk is one of the founders of BRAI3N, which aims to develop new neuromodulation treatments for conditions such as tinnitus, pain, Parkinson’s disease, depression, epilepsy, obesity, addiction, obsessive compulsive disorder, Attention Deficit Hyperactivity Disorder (ADHD), Autism, Tourette and other "tic" syndromes, and personality disorders. BRAI3N is a multidisciplinary and international collaboration between specialists in neuromodulation, neuropsychologists, audiologists, physiotherapists and neuroscientists, with labs in Ireland, the USA, New Zealand and South Korea. Since coming to New Zealand, Dirk has discovered the potential for utilising the neuroscience expertise in New Zealand to provide the theory behind proposed clinical treatments. For example, repetitive transcranial magnetic stimulation (rTMS), which involves delivering repetitive magnetic pulses to stimulate brain cells, which is currently used for stroke rehabilitation. Dirk is collaborating with a Neurological Foundation funded scientist, Professor John Reynolds from the University of Otago, Dunedin, to understand exactly how transcranial magnetic stimulation affects the brain, with the aim of enhancing the clinical application of rTMS. 1 For tinnitus research, Dirk collaborates with many international centres for human clinical research. In New Zealand specifically, he has developed collaborations with Neurological Foundation funded neuroscientists Dr Yiwen Zheng, and Professor Paul Smith from the University of Otago, Dunedin, to look for biomarkers of tinnitus. Their initial studies have shown that trauma to the auditory system can create metabolic changes that correlate with tinnitus status. 2 Obesity is also another area of concentration for Dirk and is a significant health issue in New Zealand. A particular area of the brain, the posterior cingulate cortex, has been shown to be involved in food craving in obese individuals with food We are excited to see where this new pathway will lead Dirk on his research journey and what new information his teams will discover about the human brain. addiction. In collaboration with Professor Patrick Manning in the department of endocrinology at the University of Otago, Dirk has completed a clinical trial exploring the potential therapeutic effects of Infraslow Neurofeedback (ISF-NF). Infraslow Neurofeedback is a type of neurofeedback that focuses on observing the lowest frequencies in the brain. The earliest research on these ultra-slow waves suggests ISF- NF works by regulating autonomic nervous system function, the flight, fight or freeze response. The findings from this initial small study in obese women with symptoms of food addiction showed that IFS- NF produces electrophysiological changes that may be associated with reduced food cravings. 3 This study’s findings have also been used to complete another study for the treatment of alcohol addiction in collaboration with Professor Paul Glue, Professor Patrick Manning and Dirk. In the brain, the rostrodorsal anterior cingulate cortex appears to be responsible for intense alcohol craving. Stimulating this area of the brain using implanted electrodes is showing promise for supressing alcohol craving in individuals with severe alcohol use disorder. 4 Dirk has also developed collaborations at the University of Otago looking at mild cognitive impairment with Dr Nick Cutfield, dysautonomia with Dr Luke Wilson, and pain with Drs Ramakrishnan Mani and Divya Adhia. Dirk’s most recent collaborations are looking at advanced artificial intelligence, hyper scanning, and burst stimulation. In collaboration with Professor Jeremiah Deng from Computer Sciences at the University of Otago, the goal of the advanced artificial intelligence study is to find differences between male and female brains; create objective measures for tinnitus and pain, as well as for tinnitus loudness and tinnitus related distress, and to classify different subtypes of pain and tinnitus. As of last year, Professor De Ridder is no longer the Otago Southerland Chair in Neurosurgery and the recruitment drive to fill the vacant Chair position is already underway with an enthusiastic response. Dirk has retained his Professorship at the University of Otago though and will continue his ground-breaking work in tinnitus, addiction, brain stimulation and Parkinson’s disease with fellow Neurological Foundation funded scientists and clinicians. 1 Matheson NA, Shemmell JB, De Ridder D, Reynolds JN. Understanding the Effects of Repetitive Transcranial Magnetic Stimulation on Neuronal Circuits. Front Neural Circuits. 2016;10:67. 2 He J, Zhu Y, Aa J, et al. Brain Metabolic Changes in Rats following Acoustic Trauma [published correction appears in Front Neurosci. 2017 May 08;11:260]. Front Neurosci. 2017;11:148. 3 Leong SL, Vanneste S, Lim J, Smith M, Manning P, De Ridder D. A randomised, double-blind, placebo-controlled parallel trial of closed-loop infraslow brain training in food addiction. Sci Rep. 2018;8(1):11659. 4 Leong SL, Glue P, Manning P, et al. Anterior Cingulate Cortex Implants for Alcohol Addiction: A Feasibility Study [published online ahead of print, 2020 Apr 22]. Neurotherapeutics. 2020;10.1007/s13311-020-00851-4.