This study is part of workpackage 4 of the Braintrain project (EU-FP7 n°602186), which responds to a huge clinical need for mechanism-driven therapies in psychiatry. Advances in neuroimaging and other neuroscience techniques have produced a wealth of information about the neural networks that can contribute to these disorders and their treatment (Linden, 2012). This information can now be harnessed to pinpoint both dysfunction and potential compensatory mechanisms in individual patients. It is important for the choice of neuroimaging technique that major nodes of such disordered networks are in deep regions of the brain such as subcortical nuclei (amygdala and nucleus accumbens) and/or midline cortical regions (medial prefrontal cortex, subgenual cingulate cortex, retrosplenial cortex), which are very difficult to probe via EEG alone. Through the development of fMRI-based NF (henceforth NF) techniques over the last decade by collaboration of members of this consortium (Weiskopf et al., 2004a; Weiskopf et al., 2004b), it has become a realistic proposition to train patients in the self-regulation of these networks and thus obtain clinical benefits (deCharms, 2007). In addition to this therapeutic option, NF can also take the investigation of the neural mechanisms of mental disorders to a new level because it allows the investigators to establish causal relationships by changing regional activity and assessing effects on behaviour and mental states in real-time.

In the current study, the investigators aim to provide proof of concept for using NF with adolescents with varying anxiety levels aged 14-17 years. Anxiety disorders are common, having an estimated lifetime prevalence of 10-25%, and often begin in late childhood/early adolescence. There are currently no effective prevention programmes and current treatments yield variable outcomes. Improving our understanding of the mechanisms by which anxiety disorders first develop can inform the design of effective and targeted interventions for prevention. The transition to adolescence may mark one such developmentally-sensitive juncture for the onset of lifelong persistent anxiety problems, where new interventions such as NF may be particularly effective (Cohen Kadosh et al., 2013). Particularly, it has been suggested that increased emotionality and ongoing development in the neuro-cognitive bases of emotion regulation abilities during adolescence may be one of the factors contributing to the increased risk of anxiety disorders in this age group (Haller et al., in press).

This study builds on previous work by the investigators, which has established the suitability of using NF with paediatric populations (Cohen Kadosh et al., in preparation). Specifically, here, the investigators will use NF to train 50 adolescent girls with varying anxiety levels to increase effective connectivity in the neural networks involved in emotion regulation abilities (Cohen Kadosh et al., in preparation; Kohn et al., 2014; Ruiz et al., 2013). The rationale for this approach is that by improving the information flow in these brain regions, emotion regulation abilities will also improve. Moreover, the investigators hope to be able to show that in turn, improvements in emotion regulation abilities will affect overall anxiety levels. Last, by recruiting participants across a wide range of anxiety levels, the investigators will also be able to assess variations in regulation success as a function of individual anxiety levels.