Background: Repetitive transcranial magnetic stimulation (rTMS) has been used experimentally to facilitate naming abilities in individuals with chronic post-stroke aphasia. However, little is known about how rTMS confers clinical improvement, hampering its therapeutic value. The present study investigated the characteristics of naming failure that improve following administration of continuous theta burst stimulation (cTBS)-an inhibitory form of rTMS-to the right pars triangularis (rPTr) in persons with chronic aphasia.

Objective: Sudden unexpected death in epilepsy (SUDEP) is a significant cause of mortality in epilepsy. The aim of this study is to evaluate the validity of the SUDEP-7 inventory and its components as tools for predicting SUDEP risk, and to develop and validate an improved inventory. Methods: The study included 28 patients who underwent video-electroencephalography (EEG) monitoring and later died of SUDEP, and 56 age-and sex-matched control patients with epilepsy. The SUDEP-7 score, its individual components, and an alternative inventory were examined as predictors of SUDEP. Results: SUDEP-7 scores were significantly higher among SUDEP patients compared with controls, both at time of admission (p = 0.024) and most recent follow-up (p = 0.016). SUDEP-7 scores declined only among controls, who demonstrated reduced seizure frequency. Seizure freedom after epilepsy surgery was also associated with survival. Several components of the SUDEP-7 inventory were independently associated with higher risk of SUDEP, including more than three generalized tonicclonic (GTC) seizures (p = 0.002), one or more GTC seizures (p = 0.001), or one or more seizures of any type within the last year (p = 0.013), and intellectual disability (p = 0.031). In stepwise regression models, SUDEP-7 scores did not enhance the prediction of SUDEP over either GTC seizure frequency or seizure frequency alone. A novel SUDEP-3 inventory comprising GTC seizure frequency, seizure frequency, and intellectual disability (p < 0.001) outperformed the SUDEP-7 inventory (p = 0.010) in predicting SUDEP. Significance: Our findings demonstrate the limitations of the SUDEP-7 inventory.We propose a new three-item SUDEP-3 inventory, which predicts SUDEP better than the SUDEP-7.

Recent work has combined cognitive neuroscience and control theory to make predictions about cognitive control functions. Here, we test a link between whole-brain theories of semantics and the role of the left inferior frontal gyrus (LIFG) in controlled language performance using network control theory, a branch of systems engineering. Specifically, we examined whether two properties of node controllability -boundary and modal controllability -were linked to semantic selection and retrieval on sentence completion and verb generation tasks. We tested whether the controllability of the left IFG moderated language selection and retrieval costs and the effects of continuous theta burst stimulation (cTBS), an inhibitory form of transcranial magnetic stimulation (TMS) on behavior in 41 human subjects (25 active, 16 sham). We predicted that boundary controllabilitya measure of the theoretical ability of a node to integrate and segregate brain networkswould be linked to word selection in the contextually-rich sentence completion task. In contrast, we expected that modal controllabilitya measure of the theoretical ability of a node to drive the brain into specifically hard-to-reach stateswould be linked to retrieval on the low-context verb generation task. Boundary controllability was linked to selection and to the ability of TMS to reduce response latencies on the sentence completion task. In contrast, modal controllability was not linked to performance on the tasks or TMS effects. Overall, our results suggest a link between the network integrating role of the LIFG and selection and the overall semantic demands of sentence completion. Significance StatementOur understanding of language systems and responses to neural stimulation is incomplete. Here, we demonstrate that the effects of neuromodulation (transcranial magnetic stimulation, TMS) on verbal language production are linked to the role of the left inferior frontal gyrus in mediating communication across white matter anatomical networks. We replicate prior findings in weighted anatomical networks, and further identify a link between the role of the LIFG in word selection demands. These findings provide a critical basis to reconcile local and whole brain models of language in the brain.

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