Abstracts

Rationale: Emotional disturbance can precipitate epileptic seizures. Gowers (1885) described “Of all the immediate causes of epilepsy the most potent are psychical–fright, excitement, anxiety”. Autonomic nervous system is strongly coupled to emotional state. In epilepsy, autonomic activity is typically discussed in relation to Sudden Unexpected Death (SUDEP). However, the autonomic contribution to the generation and suppression of epileptic seizures is largely over looked. In recent years, autonomic biofeedback has shown promising effects both for seizure management and for emotional regulation (Nagai et al., 2004a,b, Nagai et al., 2015, Nagai et al., 2016). Neuroimaging of the mechanisms of autonomic biofeedback for epilepsy demonstrates a link between seizure frequency reduction and functional neural connectivity changes particularly between amygdala and prefrontal cortex (Nagai et al., 2016). In the current presentation, we report changes in patients’ subjective scoring of overall seizure severity and changes in quality of life after the autonomic biofeedback therapy intervention and interaction between seizure frequency changes. Moreover, we describe neural connectivity changes and patients’ subjective feeling of anxiety/depression.  Methods: Forty patients with temporal lobe epilepsy were allocated to either therapy active (EDA biofeedback) or to control (treatment as usual) group. In the biofeedback group, the patients were given 45 minutes therapy three times a week for four weeks (12 sessions). Patients’ percentage seizure change was calculated in both groups, from seizure diaries prior to and after the therapy. Patients completed State and Trait Anxiety Inventory (STAI), Beck Depression Inventory (BDI), Seizure severity questionnaire and Quality of life questionnaire (QOLIE -10-P). Scanning (1.5T fMRI) was performed at the first session and at the last session. Resting state fMRI was processed using SPM8. Seed-based analysis was conducted with VMPFC/OFC ROI (selected from the previous finding; Nagai et al., 2004c).  Results: There was a significant difference in percentage reduction of seizure frequency between the biofeedbacktherapy and control groups (pp < 0.001: Wilcoxon Signed Rank Test) following GSR biofeedback , with a mean seizure reduction of 43%. No significant seizure reduction was observed in the control group (mean increase in seizure frequency of 31%). T-tests showed no group difference in either intensity or bothersomeness score at the beginning of the study. The patients in the therapy group showed significant reductions in seizure intensity score (p = 0.025,) and bothersomeness score (p = 0.001). Changes in amygdala functional connectivity to OFC was strongly associated with reduction in seizure frequency changes, but not with changes in anxiety score or other psychological variables.  Conclusions: Autonomic biofeedback represents an effective, non-invasive intervention. Our recent data is consistent with our previous neuroimaging studies suggesting that effect of an autonomic biofeedback is primarily physiological and subsequentlyperceived as a significant changes in seizure severity and their quality of life.  Funding: Nagai Y, et al. Epilepsy & Behaviour 2004a, 5: 216-223.Nagai Y, et al. Epilepsy Res 2004b, 58:185-193.Nagai Y, et al. Neuroimage 2004c, 22:243-251.Nagai Y, et al. Frontiers Neuroscience 2015, 17.Nagai Y et al. AES abstract, 2016