大貫 良幸

OBJECTIVE: Patients with temporal lobe epilepsy (TLE) suffer from epileptic seizures and memory decline. While focal resection eliminates seizures in 60-70% of patients, surgery carries the risk of further compromising memory. We hypothesized that hippocampal neurofeedback (NF) will induce targeted brain activity associated with memory function. METHODS: Patients with intracranial electrodes implanted in bilateral hippocampi performed a memory NF task, developed specifically for this project. The NF task involved real-time analysis of hippocampal activity using the electrode in the less-affected hippocampus while conducting a memory task. Changes in theta activity and task performance were assessed. RESULTS: The NF task was conducted in seven TLE patients. In five patients, theta activity increased significantly in the targeted hippocampus (Mann-Kendall test; p < 0.05). Mixed linear model analysis across all sessions revealed a significant increase in theta activity in the targeted hippocampus (p = 0.0032), with no significant change contralaterally (p = 0.19). Three additional TLE patients underwent random NF to assess if theta activity was induced merely by the encoding process, but none of them showed significant changes in theta activity. CONCLUSION: Memory NF task effectively induced targeted hippocampal activity in TLE patients. SIGNIFICANCE: Hippocampal NF may enhance memory function in TLE patients prior to focal resection.

BACKGROUND: Redo awake surgery is ideal for recurrent malignant gliomas in the language-dominant hemisphere, but it may not always be optimal because of inadequate awake mapping. In this report, the authors describe a case of recurrent language-dominant frontal glioma in which a super-selective Wada (ssWada) test and super-selective cone-beam CT angiography (ssCBCTA) enabled successful tumor removal under general anesthesia after awake surgery. OBSERVATIONS: A woman in her 30s underwent awake surgery for left frontal glioma recurrence 2 years after the initial resection. Three years after another recurrence, the ssWada test and ssCBCTA revealed that the tumor-supplying artery did not perfuse the functional cortex, allowing safe and maximal resection under general anesthesia. Postoperatively, she had mild motor aphasia but recovered quickly with minimal sequelae. LESSONS: The combined use of the ssWada test and ssCBCTA enables precise preoperative language mapping and safe tumor resection. Originally developed for epilepsy surgery, the ssWada test is valuable for functional mapping and, when paired with ssCBCTA, provides a 3D understanding of the lesions. This combination serves as a critical preoperative tool for tumors in the language-dominant hemisphere. https://thejns.org/doi/10.3171/CASE25384.

OBJECTIVE: This study aimed to evaluate the dynamics of the neutrophil-to-lymphocyte ratio (NLR) during the initial hospitalization of patients with eating disorders (EDs) and to assess its potential as a biomarker for monitoring disease severity and treatment response. METHODS: A retrospective chart review was conducted with 55 patients aged ≤ 16 years diagnosed with anorexia nervosa or avoidant/restrictive food intake disorder and admitted to Jichi Medical University Hospital between 2015 and 2021. Sociodemographic and clinical characteristics including sex, age, rate of weight gain, percentage of ideal body weight (%IBW), tube feeding treatment, and NLR were obtained. Statistical analyses used a mixed model for repeated measures to assess NLR changes regarding %IBW and other clinical factors. RESULTS: The NLR at admission was lower in the malnourished state but increased with weight recovery. MMRM revealed that tube feeding treatment (β = 0.538) and restoration of %IBW (β = 0.029) significantly predicted an increase in the NLR. The interaction between tube feeding and the quadratic term of %IBW was also significant, indicating distinct patterns of NLR changes: without tube feeding, NLR increased linearly with weight recovery, whereas with tube feeding, NLR exhibited a non-linear, upward-convex parabolic trend. DISCUSSION: These findings suggest that NLR may offer an objective recovery marker less influenced by patient self-report. Monitoring NLR before and after tube feeding may help distinguish true physiological recovery from transient stress responses, providing complementary information to conventional assessments. Further research is warranted to establish its clinical relevance.

Delusional misidentification, a rare syndrome in which a patient displays persistent delusional misidentification of individuals or objects, occurs in several types of dementia. However, the pathology of delusional misidentification is still unclear, and there was no data pertaining to striate-frontal projection. Here, we report a case of delusional misidentification following frontotemporal dementia in which complex striate-frontal and some specific frontal gyrus dysfunction were observed. In our presented case, delusional misidentification progressed following frontal atrophy. Believing that her actual daughter had been replaced by her niece, her symptoms of delusional misidentification and frontal atrophy progressed in the short term, and social arrangement was necessary three months after the onset. There were no abnormal neurological findings including parkinsonism and general cognitive function test scores were preserved. Validated by dopamine transporter single-photon emission computed tomography, right unilateral striatal uptake decreased significantly without parkinsonism or Parkinson's disease. In addition, of specific concern, functional magnetic resonance images showed left opercular inferior frontal gyrus and right superior frontal gyrus dysfunctions. Our case study highlights complex striate-frontal projection and specific frontal gyrus dysfunctions associated with the pathology of delusional misidentification syndrome.

The action observation network (AON) has been extensively studied using short, isolated motor acts. How activity in the network is altered when these isolated acts are embedded in meaningful sequences of actions remains poorly understood. Here we utilized intracranial electrocorticography to characterize how the exchange of information across key nodes of the AON-the precentral, supramarginal, and visual cortices-is affected by such embedding and the resulting predictability. We found more top-down beta oscillation from precentral to supramarginal contacts during the observation of predictable actions in meaningful sequences compared to the same actions in randomized, and hence less predictable, order. In addition, we find that expectations enabled by the embedding lead to a suppression of bottom-up visual responses in the high-gamma range in visual areas. These results, in line with predictive coding, inform how nodes of the AON integrate information to process the actions of others.