Relationship between neural responses to stress and mental health symptoms in psychogenic nonepileptic seizures after traumatic brain injury.

OBJECTIVE: To utilize traumatic brain injury (TBI) as a model for investigating functioning during acute stress experiences in psychogenic nonepileptic seizures (PNES) and to identify neural mechanisms underlying the link between changes in processing of stressful experiences and mental health symptoms in PNES. METHODS: We recruited 94 participants: 50 with TBI only (TBI-only) and 44 with TBI and PNES (TBI + PNES). Participants completed mood (Beck Depression Inventory-II), anxiety (Beck Anxiety Inventory), and posttraumatic stress disorder (PTSD) symptom (PTSD Checklist-Specific Event) assessments before undergoing functional magnetic resonance imaging during an acute psychosocial stress task. Linear mixed-effects analyses identified clusters of significant interactions between group and neural responses to stressful math performance and stressful auditory feedback conditions within limbic brain regions (volume-corrected α = .05). Spearman rank correlation tests compared mean cluster signals to symptom assessments (false discovery rate-corrected α = .05). RESULTS: Demographic and TBI-related measures were similar between groups; TBI + PNES demonstrated worse clinical symptom severity compared to TBI-only. Stressful math performance induced relatively greater reactivity within dorsomedial prefrontal cortex (PFC) and right hippocampal regions and relatively reduced reactivity within left hippocampal and dorsolateral PFC regions for TBI + PNES compared to TBI-only. Stressful auditory feedback induced relatively reduced reactivity within ventral PFC, cingulate, hippocampal, and amygdala regions for TBI + PNES compared to TBI-only. Changes in responses to stressful math within hippocampal and dorsal PFC regions were correlated with increased mood, anxiety, and PTSD symptom severity. SIGNIFICANCE: Corticolimbic functions underlying processing of stressful experiences differ between patients with TBI + PNES and those with TBI-only. Relationships between these neural responses and symptom assessments suggest potential pathophysiologic mechanisms in PNES.

Intermittent Theta Burst Stimulation (iTBS) for Treatment of Chronic Post-Stroke Aphasia: Results of a Pilot Randomized, Double-Blind, Sham-Controlled Trial.

BACKGROUND Research indicates intermittent theta burst stimulation (iTBS) is a potential treatment of post-stroke aphasia. MATERIAL AND METHODS In this double-blind, sham-controlled trial (NCT01512264) participants were randomized to receive 3 weeks of sham (G0), 1 week of iTBS/2 weeks of sham (G1), 2 weeks of iTBS/1 week of sham (G2), or 3 weeks of iTBS (G3). FMRI localized residual language function in the left hemisphere; iTBS was applied to the maximum fMRI activation in the residual language cortex in the left frontal lobe. FMRI and aphasia testing were conducted pre-treatment, at ≤1 week after completing treatment, and at 3 months follow-up. RESULTS 27/36 participants completed the trial. We compared G0 to each of the individual treatment group and to all iTBS treatment groups combined (G1₋3). In individual groups, participants gained (of moderate or large effect sizes; some significant at P<0.05) on the Boston Naming Test (BNT), the Semantic Fluency Test (SFT), and the Aphasia Quotient of the Western Aphasia Battery-Revised (WAB-R AQ). In G1₋3, BNT, and SFT improved immediately after treatment, while the WAB-R AQ improved at 3 months. Compared to G0, the other groups showed greater fMRI activation in both hemispheres and non-significant increases in language lateralization to the left hemisphere. Changes in IFG connectivity were noted with iTBS, showing differences between time-points, with some of them correlating with the behavioral measures. CONCLUSIONS The results of this pilot trial support the hypothesis that iTBS applied to the ipsilesional hemisphere can improve aphasia and result in cortical plasticity.

Constraint-Induced Aphasia Therapy for Treatment of Chronic Post-Stroke Aphasia: A Randomized, Blinded, Controlled Pilot Trial.

BACKGROUND: To provide a preliminary estimate of efficacy of constraint-induced aphasia therapy (CIAT) when compared to no-intervention in patients with chronic (>1 year) post-stroke aphasia in order to plan an appropriately powered randomized controlled trial (RCT). MATERIAL AND METHODS: We conducted a pilot single-blinded RCT. 24 patients were randomized: 14 to CIAT and 10 to no-intervention. CIAT groups received up to 4 hours/day of intervention for 10 consecutive business days (40 hours or therapy). Outcomes were assessed within 1 week of intervention and at 1 and 12 weeks after intervention and included several linguistic measures and a measure of overall subjective communication abilities (mini-Communicative Abilities Log (mini-CAL)). Clinicians treating patients (CIAT group) did not communicate with other team members to maintain blinding and the testing team members were blinded to treatment group assignment. RESULTS: Overall, the results of this pilot RCT support the results of previous observational studies that CIAT may lead to improvements in linguistic abilities. At 12 weeks, the treatment group reported better subjective communication abilities (mini-CAL) than the no-intervention group (p=0.019). Other measures trended towards better performance in the CIAT group. CONCLUSIONS: In this pilot RCT intensive language therapy led to an improvement in subjective language abilities. The effects demonstrated allow the design of a definitive trial of CIAT in patients with a variety of post-stroke aphasia types. In addition, our experiences have identified important considerations for designing subsequent trial(s) of CIAT or other interventions for post-stroke aphasia.

White matter and neurite morphology differ in psychogenic nonepileptic seizures.

OBJECTIVE: To further evaluate the relationship between the clinical profiles and limbic and motor brain regions and their connecting pathways in psychogenic nonepileptic seizures (PNES). Neurite Orientation Dispersion and Density Indices (NODDI) multicompartment modeling was used to test the relationships between tissue alterations in patients with traumatic brain injury (TBI) and multiple psychiatric symptoms. METHODS: The sample included participants with prior TBI (TBI; N = 37) but no PNES, and with TBI and PNES (TBI + PNES; N = 34). Participants completed 3T Siemens Prisma MRI high angular resolution imaging diffusion protocol. Statistical maps, including fractional anisotropy (FA), mean diffusivity (MD), neurite dispersion [orientation dispersion index (ODI)] and density [intracellular volume fraction (ICVF), and free water (i.e., isotropic) volume fraction (V-ISO)] signal intensity, were generated for each participant. Linear mixed-effects models identified clusters of between-group differences in indices of white matter changes. Pearson's r correlation tests assessed any relationship between signal intensity and psychiatric symptoms. RESULTS: Compared to TBI, TBI + PNES revealed decreases in FA, ICVF, and V-ISO and increases in MD for clusters within cingulum bundle, uncinate fasciculus, fornix/stria terminalis, and corticospinal tract pathways (cluster threshold α = 0.05). Indices of white matter changes for these clusters correlated with depressive, anxiety, PTSD, psychoticism, and somatization symptom severity (FDR threshold α = 0.05). A follow-up within-group analysis revealed that these correlations failed to reach the criteria for significance in the TBI + PNES group alone. INTERPRETATION: The results expand support for the hypothesis that alterations in pathways comprising the specific PNES network correspond to patient profiles. These findings implicate myelin-specific changes as possible contributors to PNES, thus introducing novel potential treatment targets.

A feasibility study of combined intermittent theta burst stimulation and modified constraint-induced aphasia therapy in chronic post-stroke aphasia.

PURPOSE: The purpose of this feasibility study was to assess whether combined intermittent theta burst suppression (iTBS) applied to the ipsilesional hemisphere and modified constraint-induced aphasia therapy (mCIAT) are safe and logistically feasible within the time interval associated with iTBS induced long-term potentiation in patients with post-stroke aphasia. We also wanted to determine whether combining priming with iTBS and CIAT improves language functions after treatment. METHODS: Twelve participants received fMRI (semantic decision/tone decision task) and neuropsychological testing of language skills at three time points - before starting the iTBS/mCIAT intervention (T1), immediately after completing 2-week long course of intervention (T2), and at 3-months follow-up (T3). ITBS was applied to the individually determined fMRI language "hot spot" located in the left fronto-temporal regions. RESULTS: There were no serious adverse events, and all mCIAT group therapy sessions (3-4 subjects each) were initiated within 30 minutes of the first group subject receiving iTBS. Neuropsychological assessments of language showed a significant effect of session on Western Aphasia Battery aphasia quotient (WAB-AQ; p = 0.04) and spontaneously correct responses on Boston Naming Test (BNT; p = 0.002), with improvement noted at T2 (p = 0.002) and T3 (p = 0.05) versus T1. FMRI showed significant changes between all timepoints. Post-hoc correlations showed associations between improvements in WAB-AQ from T2 to T3 and decreased BOLD signal in left inferior parietal lobe, and improvements in BNT from T1 to T3 with decreased signal in right inferior frontal gyrus. CONCLUSION: This study shows feasibility and safety for combining behavioral and neurostimulation interventions for chronic post-stroke aphasia. Observed changes in linguistic measures were relatively small. However, they were statistically significant and associated with parallel changes observed in the neuroimaging. Our findings support further development and testing of the combined mCIAT and iTBS protocol and comparisons to either CIAT/mCIAT or iTBS applied alone for the treatment of post-stroke aphasia.