Cognitive impairment is one of the most common symptoms of anti-leucine rich glioma inactivated 1 (anti-LGI-1) encephalitis, but little is known about the cognitive profile of these patients. This study characterized the cognitive profile of patients with anti-LGI-1 encephalitis and compared patterns of impairment to healthy controls and other patient groups with known temporal lobe/limbic involvement.

A retrospective analysis of adult patients with anti-LGI-1 encephalitis who underwent neuropsychological assessment was conducted. Performance patterns of anti-LGI-1 patients were compared to patients deemed cognitively healthy (HC), as well as patients with amnestic mild cognitive impairment (aMCI) and temporal lobe epilepsy (TLE).

Among 10 anti-LGI encephalitis patients (60% male, median age 67.5 years) who underwent neuropsychological testing (median = 38.5 months from symptom onset), cognitive deficits were common, with 100% of patients showing impairment (≤1.5 SD below mean) on 1+ measures and 80% on 2+ measures. Patients with anti-LGI-1 encephalitis performed worse than controls on measures of basic attention, vigilance, psychomotor speed, complex figure copy, and aspects of learning/memory. Of measures which differed from controls, there were no differences between the anti-LGI-1 and TLE patients, while the anti-LGI-1 patients exhibited higher rates of impairment in basic attention and lower rates of delayed verbal memory impairment compared to the aMCI patients.

Long-term cognitive deficits are common in patients with anti-LGI-1 encephalitis and involve multiple domains. Future research in larger samples is needed to confirm these findings.

Despite the importance of social cognitive functions to mental health and social adjustment, examination of these functions is absent in routine assessment of epilepsy patients. Thus, this review aims to provide a comprehensive overview of the literature on four major aspects of social cognition among temporal and frontal lobe epilepsy, which is a critical step toward designing new interventions.

Papers from 1990 to 2021 were reviewed and examined for inclusion in this study. After the deduplication process, a systematic review and meta-analysis of 44 and 40 articles, respectively, involving 113 people with frontal lobe epilepsy and 1482 people with temporal lobe epilepsy were conducted.

Our results indicated that while patients with frontal or temporal lobe epilepsy have difficulties in all aspects of social cognition relative to nonclinical controls, the effect sizes were larger for theory of mind (g = .95), than for emotion recognition (g = .69) among temporal lobe epilepsy group. The frontal lobe epilepsy group exhibited significantly greater impairment in emotion recognition compared to temporal lobe. Additionally, people with right temporal lobe epilepsy (g =  1.10) performed more poorly than those with a left-sided (g = .90) seizure focus, specifically in the theory of mind domain.

These data point to a potentially important difference in the severity of deficits within the emotion recognition and theory of mind abilities depending on the laterlization of seizure side. We also suggest a guide for the assessment of impairments in social cognition that can be integrated into multidisciplinary clinical evaluation for people with epilepsy

Surgical treatment of drug-resistant temporal lobe epilepsy (TLE) depends on proper identification of the seizure onset zone (SOZ) and differentiation of mesial, temporolimbic seizure onsets from temporal neocortical seizure onsets. Noninvasive source imaging using electroencephalography (EEG) and magnetoencephalography (MEG) can provide accurate information on interictal spike localization; however, EEG and MEG have low sensitivity for epileptiform activity restricted to deep temporolimbic structures. Moreover, in mesial temporal lobe epilepsy (MTLE), interictal spikes frequently arise in neocortical foci distant from the SOZ, rendering interictal spike localization potentially misleading for presurgical planning.

In this study, we used two different beamformer techniques applied to the MEG signal of ictal events acquired during EEG-MEG recordings in six patients with TLE (three neocortical, three MTLE) in whom the ictal source localization results could be compared to ground truth SOZ localizations determined from intracranial EEG and/or clinical, neuroimaging, and postsurgical outcome evidence.

Beamformer analysis proved to be highly accurate in all cases and was able to identify focal SOZs in mesial, temporolimbic structures. In three patients, interictal spikes were absent, too complex for dipole modeling, or localized to anterolateral temporal neocortex distant to a mesial temporal SOZ, and thus unhelpful in presurgical investigation.

MEG beamformer source reconstruction is suitable for analysis of ictal events in TLE and can complement or supersede the traditional analysis of interictal spikes. The method outlined is applicable to any type of epileptiform event, expanding the information value of MEG and broadening its utility for presurgical recording in epilepsy.

Adults with temporal lobe epilepsy (TLE) have been found to have a fairly characteristic pattern of neuropsychological performance, but there is considerably less research and more variability in findings with children. Because the cognitive domains included in most studies with children have been limited, the current study attempted to better characterize the cognitive phenotype of children with TLE using a broader neuropsychological battery.

The study included 59 children with TLE (59% male) age 7 to 16 (M = 12.67; SD = 3.12) who underwent comprehensive neuropsychological evaluation. Patient results were grouped into cognitive domains (reasoning, language, visuoperceptual, verbal memory, executive function, and motor function) based upon their test performance. These factor scores were subjected to Ward’s hierarchical clustering method with squared Euclidean distance.

Cluster analysis revealed three distinct cognitive profiles: (1) normal functioning (20% of sample); (2) delayed verbal memory and motor weaknesses (61% of the sample); and (3) global impairment (19% of the sample). Cluster 3 had longer epilepsy duration and a higher incidence of hippocampal sclerosis (HS) compared to Cluster 1 (p < .05). There were no significant differences among the three cluster groups on demographic characteristics or remaining clinical characteristics.

Children with TLE present with distinct cognitive phenotypes ranging from average performance to global impairment. Results partially support previous hypotheses highlighting the cumulative neurobiological burden on the developing brain in the context of chronic epilepsy and provide a preliminary framework for the cognitive domains most vulnerable to the TLE disease process.

We present the case of a 34-year-old female patient with no prior psychiatric record who was treated in our outpatient department due to persecutory delusions of recent onset. The patient had a history of refractory temporal epilepsy since adolescence and underwent a temporal lobe resection 4 month prior to the appearance of her symptoms.

Temporal lobe resection is a well-established technique to treat refractory temporal lobe epilepsy in which psychotic symptoms are an infrequent complication; the most frequent being cognitive sequelae, visual field defects and depression. According to several sources, this symptomatology may be underdiagnosed and undereportend and there have been a number of case reports and series of cases which describe the aforementioned entity.

A case report is presented alongside a review of the relevant literature regarding cases of secondary psychosis after brain surgery.

During her treatment we administered olanzapine up to doses of 7.5mg per day because of the risk of reducing the convulsive threshold. We observed a marked improvement and the disappearance of the delusions. The dose of olanzapine has been maintained for a year with no important side-effects and without a relapse in symptoms.

Psychotic symptoms as a complication of temporal lobe resection may be more frequent than what was thought in the past. It is important to study this phenomenon more in-depth because the symptoms may remain undetected and present worse outcomes given that there are effective treatments which could ameliorate the condition.

No significant relationships.

Recent literature documents a trend of gradual decline in temporal lobe (resective) epilepsy surgery over the past decade. Amongst these, a large scale, comprehensive survey done in selected European, Australian and American centres documents trends of resective temporal epilepsy surgery across two decades. Montreal Neurological Institute has been the leading epilepsy surgery centre for more than 50 years now. It has been at the forefront of investigating and managing epilepsy in Canada. We have looked into the trends of epilepsy surgery in our institute in the past 44 years.

The records of all adult epilepsy surgery procedures (excluding reoperations) performed by the senior authors were analysed from 1971 to 2015. Data retrieved for analysis included type of surgery (intracranial recording, resective, and neuromodulatory) and the specific surgical target for resection. Procedures were grouped into temporal resective, extratemporal (ET) resective and placement of intracranial electrodes (stereotactic electroencephalogram (SEEG)).

A total of 2,078 new procedures were performed from 1971 to 2015 at the Montreal Neurological Institute. Temporal procedures constituted the bulk of the proportion of all procedures each year and the entire study period. SEEG group shows linear increase in the number of cases over the years catching up with the total number of temporal procedures.

Our study involving a homogenous dataset spanning nearly 50 years shows a decline in temporal lobe surgeries and an increase in intracranial investigations despite the class I evidence of its effectiveness. This corroborates the trends in epilepsy surgery practice profiles in tertiary centres of developed countries.

We investigated motor cortical excitability (CE) in unilateral temporal lobe epilepsy (TLE) and its relationship to bilateral tonic-clonic seizure (BTCS) using paired-pulse transcranial magnetic stimulation (TMS).

In this cross-sectional study, we enrolled 46 unilateral TLE patients and 16 age-and sex-matched healthy controls. Resting motor thresholds (RMT); short-interval intracortical inhibition (SICI, GABAA receptor-mediated); facilitation (ICF, glutamatergic-mediated) with interstimulus intervals (ISIs) of 2, 5, 10, and 15 ms; and long-interval intracortical inhibition (LICI, GABAB receptor-mediated) with ISIs of 200–400 ms were measured via paired-pulse TMS. Comparisons were made between controls and patients with TLE, and then among the TLE subgroups (no BTCS, infrequent BTCS and frequent BTCS subgroup).

Compared with controls, TLE patients had higher RMT, lower SICI and higher LICI in both hemispheres, and higher ICF in the ipsilateral hemisphere. In patients with frequent BTCS, cortical hyperexcitability in the ipsilateral hemisphere was found in a parameter-dependent manner (SICI decreased at a stimulation interval of 5 ms, and ICF increased at a stimulation interval of 15 ms) compared with patients with infrequent or no BTCS.

Our results demonstrate that motor cortical hyper-excitability in the ipsilateral hemisphere underlies the epileptogenic network of patients with active BTCS, which is more extensive than those with infrequent or no BTCS.

“Temporal plus” epilepsy (TPE) is a term that is used when the epileptogenic zone (EZ) extends beyond the boundaries of the temporal lobe. Stereotactic electroencephalography (SEEG) has been essential to identify additional EZs in adjacent structures that might be part of the temporal lobe/limbic network.

We present a small case series of temporal plus cases successfully identified by SEEG who were seizure-free after resective surgery.

We conducted a retrospective analysis of 156 patients who underwent SEEG in 5 years. Six cases had TPE and underwent anterior temporal lobectomy (ATL) with additional extra-temporal resections.

Five cases had a focus on the right hemisphere and one on the left. Three cases were non-lesional and three were lesional. Mean follow-up time since surgery was 2.9 years (SD ± 1.8). Three patients had subdural electrodes investigation prior or in addition to SEEG. All patients underwent standard ATL and additional extra-temporal resections during the same procedure or at a later date. All patients were seizure-free at their last follow-up appointment (Engel Ia = 3; Engel Ib = 2; Engel Ic = 1). Pathology was nonspecific/gliosis for all six cases.

TPE might explain some of the failures in temporal lobe epilepsy surgery. We present a small case series of six patients in whom SEEG successfully identified this phenomenon and surgery proved effective.