Impairments in processing speed under conditions of increasing cognitive load have been reported in individuals with mild traumatic brain injury (mTBI). In other conditions that are also associated with white matter disruption, both psychological distress and fatigue have been shown to underlie this impairment. Objective: the current study aimed to investigate whether slowing of processing abilities under conditions of greater cognitive load is independent of fatigue and psychological status in premorbidly healthy individuals with subacute mTBI. Method: using a prospective observational design, we examined 84 individuals with mTBI approximately 8 weeks after injury and 47 healthy control (HC) participants. They were assessed with the Symbol Digit Modality Test, an n-back task and a rate of gain of information choice reaction time task that conforms to Hick’s law. Participants were also assessed with measures of fatigue and psychological status. Results: as expected, findings revealed no group differences on simple reaction time tasks, but as task complexity increased, the mTBI group performed more slowly than the HC group. This group difference occurred independently of fatigue and psychological distress levels and was associated with a moderate effect size. Conclusions: during the subacute period after mTBI, premorbidly healthy individuals demonstrate impairment in their ability to rapidly process information as the cognitive load of the task increases beyond simple reaction time requirements. Examination of whether these changes affect resumption of premorbid roles is warranted.

ObjectiveCortical stimulation is an important component of stereoelectroencephalography (SEEG). Despite this, there is currently no standardized approach and significant heterogeneity in the literature regarding cortical stimulation practices. Via an international survey of SEEG clinicians, we sought to examine the spectrum of cortical stimulation practices to reveal areas of consensus and variability.MethodsA 68‐item questionnaire was developed to understand cortical stimulation practices including neurostimulation parameters, interpretation of epileptogenicity, functional and cognitive assessment and subsequent surgical decisions. Multiple recruitment pathways were pursued, with the questionnaire distributed directly to 183 clinicians.ResultsResponses were received from 56 clinicians across 17 countries with experience ranging from 2 to 60 years (M = 10.73, SD = 9.44). Neurostimulation parameters varied considerably, with maximum current ranging from 3 to 10 mA (M = 5.33, SD = 2.29) for 1 Hz and from 2 to 15 mA (M = 6.54, SD = 3.68) for 50 Hz stimulation. Charge density ranged from 8 to 200 μC/cm2, with up to 43% of responders utilizing charge densities higher than recommended upper safety limits, i.e. 55 μC/cm2. North American responders reported statistically significant higher maximum current (P < 0.001) for 1 Hz stimulation and lower pulse width for 1 and 50 Hz stimulation (P = 0.008, P < 0.001, respectively) compared to European responders. All clinicians evaluated language, speech, and motor function during cortical stimulation; in contrast, 42% assessed visuospatial or visual function, 29% memory, and 13% executive function. Striking differences were reported in approaches to assessment, classification of positive sites, and surgical decisions guided by cortical stimulation. Patterns of consistency were observed for interpretation of the localizing capacity of stimulated electroclinical seizures and auras, with habitual electroclinical seizures induced by 1 Hz stimulation considered the most localizing.SignificanceSEEG cortical stimulation practices differed vastly across clinicians internationally, highlighting the need for consensus‐based clinical guidelines. In particular, an internationally standardized approach to assessment, classification, and functional prognostication will provide a common clinical and research framework for optimizing outcomes for people with drug‐resistant epilepsy.

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IntroductionPrenatal exposure to certain antiseizure medications (ASMs) has been associated with increased risk of adverse neurodevelopmental outcomes in offspring. While the cognitive and intellectual outcomes of ASM-exposed offspring have been well-described, the long-term behavioural and functional sequalae in these children have received less attention. This systematic review aims to synthesise evidence on the relationship between prenatal ASM exposure and postnatal adverse neurodevelopmental outcomes, focusing on non-cognitive and intellectual domains of neurodevelopment including reduced social, emotional, behavioural, and adaptive functioning, as well as the frequency of neurodevelopmental and psychiatric disorders. This will have meaningful clinical implications for how we counsel women taking ASMs in pregnancy.Methods and analysisStudies reporting predefined neurodevelopmental outcomes will be identified by electronic searches of MEDLINE, PsychINFO, EMBASE, as well as additional manual and grey literature searches. Eligible studies will report outcomes of offspring exposed to ASMs in utero either prospectively or retrospectively from 1990 to present, with screening performed in duplicate. We will use the Newcastle-Ottawa Scale to conduct methodological quality assessments of included observational studies. A narrative synthesis will be used to report on the review findings. Meta-analysis is not anticipated.Ethics and disseminationEthics clearance is not required for the current study. The systematic review will be prepared as a journal article and published in a peer-reviewed journal upon completion.PROSPERO registration numberPROSPERO CRD42021281919Article SummaryStrengths and limitations of this studyThis protocol was developed and written according to the PRISMA-P guidelinesPublication of this protocol ensures transparency and reproducibility of the methods of the systematic review, as well as reduces the likelihood of review duplicationRestricting publications to English only may introduce bias whereby some relevant data is not includedMeta-analysis is not likely to be possible due to heterogeneity in study methodology, reducing the strength of the conclusions that can be drawnTargeting psychosocial and behavioural outcomes allows for a more nuanced understanding of the long-term clinical consequences of prenatal ASM-exposure