LAUSR

In this project, we studied the efficacy of focused inhibitory stimulation using continuous theta burst stimulation (cTBS) repetitive transcranial magnetic stimulation (rTMS) on an easily accessible region of the default mode network (DMN). As reported elsewhere, we found that cTBS improved brain connectivity and objectively measured sleep. However, there is little known about the side effects of rTMS in the treatment of insomnia, so here we evaluated the effects on verbal memory recall. Twenty adults with clinical insomnia completed this study (Mage=26.90, SD=6.56). Participants conducted two overnight visits during the study; one where they received active cTBS and one where they received a sham cTBS prior to sleep. Participants completed the California Verbal Learning Test (CVLT) before stimulation and again completed the recall portion following a night of laboratory monitored sleep. We analyzed CVLT recall performance with a repeated measures ANOVA with factors of condition (active cTBS vs. sham cTBS) and session (Short Recall, Long Recall, Cued Recall, and Recognition). Contrary to our hypothesis, our analyses indicate there was no significant effects on recall performance due to active cTBS. There was no main effect of condition on recall scores post-TMS administration (F(1, 18)=1.162, p=.220, ηp2 = 0.082). There was no interaction effect of active or sham cTBS on recall performance (F(4, 15)=.828, p=.528, ηp2=0.181). Posthoc pairwise comparisons demonstrated that there was no significant difference post-TMS administration between active cTBS and sham cTBS conditions on long recall, cued recall, or recognition (p>.05). There was no significant difference post-TMS administration on short-term recall performance. Participants scored lower on short term recall after receiving active cTBS (M=12.632; SD=2.910) than after sham cTBS administration (M=13.42 ;SD=2.545) (p=.048). Compared to sham, active cTBS was not associated with any significant difference in long-term recall performance after TMS administration. While the results demonstrate there are short term effects to recall after administration, recall scores bounce back shortly after. While participants didn’t necessarily improve with active cTBS, it is beneficial to know there are no long-term harmful effects of active cTBS on recall as side effect of insomnia treatment. W81XWH2010173