Practical approach to the child presenting with acute generalised weakness.

Acute generalised muscle weakness in children is a paediatric emergency with a broad differential diagnosis. A careful history and neurologic examination guides timely investigation and management. We review some of the more common causes of acute generalised muscle weakness in children, highlighting key history and examination findings, along with an approach to lesion localisation to guide differential diagnosis and further investigation.

A nationwide survey of facial onset sensory and motor neuronopathy in Japan.

The epidemiology and etiology of facial onset sensory and motor neuronopathy (FOSMN), a rare syndrome that initiates with facial sensory disturbances followed by bulbar symptoms, remain unknown. To estimate the prevalence of FOSMN in Japan and establish the characteristics of this disease, we conducted a nationwide epidemiological survey. In the primary survey, we received answers from 604 facilities (49.8%), leading to an estimated number of 35.8 (95% confidential interval: 21.5-50.2) FOSMN cases in Japan. The secondary survey collected detailed clinical and laboratory data from 21 cases. Decreased or absent corneal and pharyngeal reflexes were present in over 85% of the cases. Electrophysiological analyses detected blink reflex test abnormalities in 94.1% of the examined cases. Immunotherapy was administered in 81% of cases and all patients received intravenous immunoglobulin. Among them, 35.3% were judged to have temporary beneficial effects evaluated by the physicians in charge. Immunotherapy tended to be effective in the early stage of disease. The spreading pattern of motor and sensory symptoms differed between cases and the characteristics of the motor-dominant and sensory-dominant cases were distinct. Cases with motor-dominant progression appeared to mimic amyotrophic lateral sclerosis. This is the first nationwide epidemiological survey of FOSMN in Japan. The clinical course of FOSMN is highly variable and motor-dominant cases developed a more severe condition than other types of cases. Because clinical interventions tend to be effective in the early phase of the disease, an early diagnosis is desirable.

WHIGET and TETRAS Ratings of Action Tremor in Patients with Essential Tremor: Substantial Association and Agreement.

Background: Evaluating tremor severity is a critical component of diagnosing and clinically managing patients with essential tremor (ET). We examined the comparability of tremor severity ratings derived from two frequently used tremor rating scales: the Washington Heights-Inwood Genetic Study of Essential Tremor (WHIGET) rating scale and the Tremor Research Group Essential Tremor Rating Scale (TETRAS). Methods: A trained assistant administered and videotaped a neurological examination, including eight items assessing upper limb action tremor (arms outstretched, arms in the wingbeat position, finger-nose-finger maneuver, and drawing of Archimedes spirals). An experienced movement disorders neurologist reviewed the videos and assigned WHIGET and TETRAS ratings. We calculated associations between TETRAS and WHIGET ratings using Spearman rank order correlations. Subsequently, we collapsed these ratings into four tremor severity categories (absent, mild, moderate, severe) and then two broader tremor severity categories (absent/mild, moderate/severe). We calculated weighted Kappa coefficients to assess agreement between category assignments based on the TETRAS and the WHIGET. Results: Spearman's r' s were significant for all items (p's ≤ 0.001, mean r = 0.89). Weighted Kappa's revealed substantial to near perfect agreement for all eight items (mean k = 0.86, range = 0.64 to 1.00). Conclusion: Analyses revealed substantial strength of association and substantial to near perfect agreement between items rated with the WHIGET and TETRAS scales. These data indicated that ratings provided by each scale are highly comparable.

Realness of face images can be decoded from non-linear modulation of EEG responses.

Artificially created human faces play an increasingly important role in our digital world. However, the so-called uncanny valley effect may cause people to perceive highly, yet not perfectly human-like faces as eerie, bringing challenges to the interaction with virtual agents. At the same time, the neurocognitive underpinnings of the uncanny valley effect remain elusive. Here, we utilized an electroencephalography (EEG) dataset of steady-state visual evoked potentials (SSVEP) in which participants were presented with human face images of different stylization levels ranging from simplistic cartoons to actual photographs. Assessing neuronal responses both in frequency and time domain, we found a non-linear relationship between SSVEP amplitudes and stylization level, that is, the most stylized cartoon images and the real photographs evoked stronger responses than images with medium stylization. Moreover, realness of even highly similar stylization levels could be decoded from the EEG data with task-related component analysis (TRCA). Importantly, we also account for confounding factors, such as the size of the stimulus face's eyes, which previously have not been adequately addressed. Together, this study provides a basis for future research and neuronal benchmarking of real-time detection of face realness regarding three aspects: SSVEP-based neural markers, efficient classification methods, and low-level stimulus confounders.

Translation and measurement properties of the Portuguese-Brazil version of the Hammersmith Infant Neurological Examination (HINE-Br).

OBJECTIVE: The current study aimed to translate the Hammersmith Infant Neurological Examination (HINE) into Brazilian Portuguese and analyze the reliability of the translated version for a population of Brazilian infants. METHODS: This was a methodological study, approved by the Ethics Committee, carried out between June 2020 and May 2021. HINE is a standardized clinical neurological examination used for the early detection of cerebral palsy. The quantitative section, "neurological examination", contains 26 items scored from 0 to 3 points, divided into five categories: cranial nerve function, posture, movements, muscle tone and reflexes, and reactions. The HINE translation followed four steps: translation, synthesis, back-translation, and evaluation by an expert committee. To verify the reliability of the HINE-Br (Portuguese-Brazil version) two independent examiners evaluated 43 infants, between 3 and 22 months of age. Internal consistency was verified by Cronbach's Alpha coefficient and interrater reliability by the intraclass correlation coefficient (ICC). RESULTS: The translated version was similar to the original version and a few semantic and idiomatic adjustments were necessary. Appropriate internal consistency (Alpha=0.91) was found for the 26 items of the HINE-Br, as well as strong interrater reliability for the total score (ICC2.1=0.95), and also for the five categories (ICC2.1=0.83-0.95). CONCLUSIONS: The HINE-Br presents adequate rates of internal consistency and interrater reliability, and can be used for the evaluation of children at risk for cerebral palsy, between 3 and 24 months of age, by pediatricians and pediatric physical therapists.

Validation of the Slovenian version of the Montreal Cognitive Assessment Scale as a screening tool for the detection of mild cognitive impairment.

OBJECTIVE: The Montreal cognitive assessment scale (MoCA) is commonly used for detecting individuals with mild cognitive impairment (MCI). The aim of the present study was to evaluate the validity of the Slovenian MoCA as a screening tool for MCI and to determine the optimal cut-off point to detect MCI in the elderly population. METHODS: Mini-Mental State Examination (MMSE), MoCA, and neuropsychological testing assessment were conducted on 93 individuals aged ≥ 60 years. MCI was found in 35 individuals with 58 cognitively asymptomatic controls. Cut-off values, sensitivity, and specificity of MoCA were calculated with the receiver operating characteristic curve. RESULTS: MCI and healthy individuals did not differ with respect to age and education. Healthy individuals (M = 24.5, SD = 1.7) performed significantly better on MoCA compared to MCI individuals (M = 21.4, SD = 3.2) (p < 0.001). The Cronbach's α of MoCA as an index of internal consistency was 0.64. MoCA distinguished between healthy controls and MCI individuals with a sensitivity of 77% and specificity of 74%, using a cut-off of 23/24 points. CONCLUSION: The Slovenian version of MoCA demonstrates an optimal cut-off value of 23/24 points for detecting older individuals with MCI. As a screening tool for MCI, its better diagnostic accuracy makes it preferable to using MMSE.

Reliability of the Montreal Cognitive Assessment in people with stroke.

This study examined the relative and absolute reliability of the Taiwanese version of the MoCA (MoCA-T) in people with stroke. The study recruited 114 individuals who were at least 3 months after the onset of a first-ever unilateral stroke. The MoCA-T was administered twice, at a 6-week interval, to all participants. The relative reliability was assessed using the intraclass correlation coefficient (ICC), and the absolute reliability was assessed using standard error of measurement (SEM), the smallest real difference (SRD), the SRD percentage, and the Bland-Altman method. The ICC analysis showed the MoCA-T was highly reliable (ICC = 0.85). The absolute reliability was between an acceptable and excellent level, where the SEM and the SRD at the 95% confidence interval were 1.38 and 3.83, respectively. The Bland-Altman analyses showed no systematic bias between repeated measurements. The range of the 95% limits of agreement was narrow, indicating a high level of stability over time. These findings suggest that the MoCA-T has high agreement between repeated measurements without systematic bias. The threshold to detect real change stands between an acceptable and excellent level. The MoCA-T is a reliable tool for cognitive screening in stroke rehabilitation.

Effects of motion type on motion-onset and steady-state visual evoked potentials: rotation vs. flicker.

The underlying mechanisms of information processing for two basic motion types, rotation and flicker, are not fully understood. Rotational and flickering animations at four speeds - 7 frames per second (fps), 8 fps, 11 fps, and 12 fps, respectively - are presented as visual stimuli. The motion-onset visual evoked potentials (VEPs) and steady-state VEPs (SSVEP) elicited by these motion stimuli were compared between the rotation and flicker motion types at time windows of 0-500 ms and 1000-5000 ms post-stimulus, respectively. The standardized low-resolution electromagnetic tomography (sLORETA) source localization was investigated as well. Four motion speeds had no effect on the whole VEP waveform in either the rotation or the flicker groups. Significant differences in motion-onset VEPs and sLORETA source localization were found between the rotation and the flicker motion types at time windows of 200-500 ms post-stimulus. For the time windows of 1000-5000 ms post-stimulus, both the rotation and flicker groups all demonstrated the characteristics of SSVEP, with the peak spectral topographies showing at the four different frequencies, which correspond to the four motion speeds. Additionally, a higher power of spectral topography at each of the four motion speeds was found in the rotation relative to the flicker stimulation. The perceptual and cognitive processes are distinct for two types of motion: rotation and flicker. In terms of motion-onset VEPs and the characteristics of SSVEP, rotating visual stimulation is superior to flicker stimulation and may be more appropriate for clinical and engineering applications.

Migraine in children and adolescents: Assessment and diagnosis.

Migraine is a complex, multifactorial brain disorder, and its presentation, complications, and response to treatment often follow the biopsychosocial model. Therefore, assessment and management include the wider aspects of the child's life within the family, at school, with peers, and in relation to his/her neurologic and emotional development. The diagnosis of headache disorders in children relies heavily on taking a careful clinical history, carrying out an appropriate physical and neurologic examination and a skilled interpretation of the findings. This chapter discusses the peculiarities of migraine in children, the differences in presentation from that in adults, and the skills that are needed in assessing the children and adolescents with headache. There is also a brief review of the epidemiology of headache and migraine in children and adolescents and an introduction of the principles of a comprehensive clinical assessment of the impact of migraine on child's quality of life. Several important elements of the clinical history and the physical and neurologic examination will be illustrated to help in the early detection of red flags that may necessitate further assessment and/or investigations. At the end of the assessment, the clinicians will be able to employ the International Classification of headache Disorders and make the correct diagnosis.

Agreement between Hammersmith Neonatal Neurological Examination (HNNE) and Test of Infant Motor Performance (TIMP) in neurodevelopmental assessment of preterm infants <32 weeks' gestation at term corrected age.

OBJECTIVES: To determine the agreement between HNNE and TIMP at TCA for preterm infants born <32+0 weeks' gestation, and to evaluate their correlation to PDMS-2 at 12-month corrected age (CA). METHODS: Infants born between November 2013 to June 2022 who had both HNNE and TIMP performed at TCA of 37+0-41+6 weeks gestation, and motor outcome assessed using the PDMS-2 at 12-month old were enrolled. The HNNE and 12-month PDMS-2 findings were categorized as optimal vs sub-optimal. TIMP was categorized as typical vs atypical. Cohen's kappa was used to determine the agreement between HNNE and TIMP. Sensitivity analysis and Receiver Operating Characteristic (ROC) curves were used to evaluate the predictive values of HNNE and TIMP on motor outcome at CA of 12-months. RESULTS: HNNE and TIMP done on 125 infants at TCA do not show reliable agreement. HNNE demonstrated slight and fair agreement with the 12-month Total Motor Quotient (TMQ) and Fine Motor Quotient (FMQ) of the PDMS-2 respectively. TIMP at TCA demonstrated fair agreement with all sub-domains of motor function on PDMS-2 at 12-months. In comparison with TIMP, HNNE at TCA is more sensitive at predicting suboptimal total, gross and fine motor outcomes at 12-month CA with sensitivity of 68.4 %, 51.9 %, and 83.3 % vs 44.4 %, 31.8 % and 53.3 % respectively. Atypical TIMP at TCA is more specific for suboptimal total, gross and fine motor outcomes at 12-month CA with specificity of 90.3 %, 89 % and 90.5 % respectively. Neurobehavioral assessments at TCA using HNNE and TIMP were predictive of suboptimal fine motor quotient at CA of 12-months with AUC of 0.760 (p = 0.011) and 0.718 (p = 0.032) respectively. The difference in AUC between the 2 instruments of 0.042 was not statistically significant (p = 0.741). CONCLUSIONS: While the HNNE and TIMP done at TCA did not demonstrate significant agreement, suboptimal HNNE and atypical TIMP at TCA were predictive of suboptimal FMQ on PDMS-2 at 12-month CA.

Diagnostic accuracy of the Clock Drawing Test in screening for early post-stroke neurocognitive disorder: the Nor-COAST study.

BACKGROUND: Post-stroke neurocognitive disorder, though common, is often overlooked by clinicians. Moreover, although the Montreal Cognitive Assessment (MoCA) has proven to be a valid screening test for neurocognitive disorder, even more time saving tests would be preferred. In our study, we aimed to determine the diagnostic accuracy of the Clock Drawing Test (CDT) for post-stroke neurocognitive disorder and the association between the CDT and MoCA. METHODS: This study is part of the Norwegian Cognitive Impairment After Stroke study, a multicentre prospective cohort study following patients admitted with acute stroke. At the three-month follow-up, patients were classified with normal cognition, mild neurocognitive disorder, or major neurocognitive disorder according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition criteria. Any neurocognitive disorder compromised both mild- and major neurocognitive disorder. The CDT at the three-month assessment was given scores ranging from 0 to 5. Patients able to complete the CDT and whose cognitive status could be classified were included in analyses. The CDT diagnostic accuracy for post-stroke neurocognitive disorder was identified using receiver operating characteristic curves, sensitivity, specificity, positive predictive value, and negative predictive value. The association between the MoCA and CDT was analysed with Spearman's rho. RESULTS: Of 554 participants, 238 (43.0%) were women. Mean (SD) age was 71.5 (11.8) years, while mean (SD) National Institutes of Health Stroke Scale score was 2.6 (3.7). The area under the receiver operating characteristic curve of the CDT for major neurocognitive disorder and any neurocognitive disorder was 0.73 (95% CI, 0.68-0.79) and 0.68 (95% CI, 0.63-0.72), respectively. A CDT cutoff of < 5 yielded 68% sensitivity and 60% specificity for any neurocognitive disorder and 78% sensitivity and 53% specificity for major neurocognitive disorder. Spearman's correlation coefficient between scores on the MoCA and CDT was 0.50 (95% CI, 0.44-0.57, p < .001). CONCLUSIONS: The CDT is not accurate enough to diagnose post-stroke neurocognitive disorder but shows acceptable accuracy in identifying major neurocognitive disorder. Performance on the CDT was associated with performance on MoCA; however, the CDT is inferior to MoCA in identifying post-stroke neurocognitive disorder. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02650531). Retrospectively registered January 8, 2016.

Neurological examination of clinically healthy pigeons (Columba livia domestica), mute swans (Cygnus olor), common buzzards (Buteo buteo), common kestrels (Falco tinnunculus) and northern goshawks (Accipiter gentilis).

BACKGROUND: A neurological examination is essential for determining the localisation of neurological lesions. However, in avian species, quantitative data regarding the practicability and feasibility of neurological tests are very limited. Therefore, the aim of this study was to establish normative data for the neurological examination of clinically healthy birds of different species. METHODS: Forty-two domestic and feral pigeons (Columba livia domestica), 42 mute swans (Cygnus olor), 12 common buzzards (Buteo buteo), 24 common kestrels (Falco tinnunculus) and six northern goshawks (Accipiter gentilis) were examined. All birds underwent a predefined neurological examination. Interobserver variations between three examiners were investigated in 11 pigeons and 11 mute swans. RESULTS: All postural reaction tests, except for the drop and flap reaction in mute swans, provoked a consistent response in pigeons and mute swans, whereas postural reaction tests of the legs in raptors were often not performable. Cranial nerve tests and most of the spinal reflexes revealed variable responses in all birds. The gastrocnemius reflex was not provokable in any bird. Interobserver agreement was almost perfect (Gwet's AC1 coefficient ≥0.81) for 16 of 21 parameters in the examination in pigeons and for 14 of 21 in mute swans. LIMITATIONS: The inclusion of free-ranging birds, which were not used to handling and for which limited information regarding age, history of previous diseases, etc. was available, may have influenced the results. CONCLUSION: The normative neurological examination data provided in this study will help improve clinicians' interpretation of neurological examination results in the respective bird species.

Tactile stimulation of the perigenital region during manual bladder expression improved the urine stream in cats affected by upper motor neuron injury.

OBJECTIVE: The aim of the study was to evaluate whether the tactile stimulation of the perigenital region together with manual bladder expression (MBE) facilitated the urine stream in cats with acute or chronic upper motor neuron injury (UMNI). ANIMALS: 34 cats with UMNI having urinary retention. METHODS: All the cats had a complete neurologic examination, which determined the localization of the UMNI between T3 and L3. They were classified as chronic UMNI if the injury had occurred more than 3 days previously. The cats were divided equally into 2 groups: the M group (n = 17) managed with only MBE, and the MT group (17) managed with MBE and tactile stimulation. RESULTS: In both groups, all the cats affected by chronic UMNI resumed urination. The time required to obtain a urine stream in the chronic UMNI was 9.3 seconds in the M group and 3.1 seconds in the MT group (P < .05). In the cats affected by acute UMNI, a urine stream was achieved in 54% of the M group and 100% of the MT group (P < .05). The time to obtain a urine stream in the acute UMNI cats was 7.8 seconds in the M group and 3.75 seconds in the MT group (P < .05). CLINICAL RELEVANCE: Adding tactile stimulation of the perigenital region to the MBE improved the urine stream in cats affected by UMNI.

The semicircular canal function is preserved with little impact on falls in patients with mild Parkinson's disease.

INTRODUCTION: Postural instability is a cardinal symptom of Parkinson's disease (PD), which suggests the vestibular system may be affected in PD. This study aimed to determine whether vestibular dysfunction is associated with the risk of falls in PD. METHODS: We prospectively recruited patients with de-novo PD at a tertiary medical center between December 2019 and March 2023. During initial assessment, each patient was queried about falls within the preceding year. All patients underwent evaluation of video head-impulse tests (video-HITs), motion analysis, mini-mental state examination (MMSE), and Montreal Cognitive Assessment (MOCA). We determined whether head impulse gain of the vestibulo-ocular reflex (VOR) was associated with clinical severity of PD or risk of falls. RESULTS: Overall, 133 patients (mean age ± SD = 68 ± 10, 59 men) were recruited. The median Movement Disorder Society-Unified Parkinson's Disease Rating Scale motor part (MDS-UPDRS-III) was 23 (interquartile range = 16-31), and 81 patients (61 %) scored 2 or less on the Hoehn and Yahr scale. Fallers were older (p = 0.001), had longer disease duration (p = 0.001), slower gait velocity (p = 0.009), higher MDS-UPDRS-III (p < 0.001) and H&Y scale (p < 0.001), lower MMSE (p = 0.018) and MOCA scores (p = 0.001) than non-fallers. Multiple logistic regression showed that MDS-UPDRS-III had a positive association with falling (p = 0.004). Falling was not associated with VOR gain (p = 0.405). The VOR gain for each semicircular canal showed no correlation with the MDS-UPDRS-III or disease duration. CONCLUSIONS: The semicircular canal function, as determined by video-HITs, is relatively spared and has little effect on the risk of falls in patients with mild-to-moderate PD.

A Single Dermatome Clinical Prediction Rule for Independent Walking 1 Year After Spinal Cord Injury.

OBJECTIVE: To derive and validate a simple, accurate CPR to predict future independent walking ability after SCI at the bedside that does not rely on motor scores and is predictive for those initially classified in the middle of the SCI severity spectrum. DESIGN: Retrospective cohort study. Binary variables were derived, indicating degrees of sensation to evaluate predictive value of pinprick and light touch variables across dermatomes. The optimal single sensory modality and dermatome was used to derive our CPR, which was validated on an independent dataset. SETTING: Analysis of SCI Model Systems dataset. PARTICIPANTS: Individuals with traumatic SCI. The data of 3679 participants (N=3679) were included with 623 participants comprising the derivation dataset and 3056 comprising the validation dataset. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Self-reported ability to walk both indoors and outdoors. RESULTS: Pinprick testing at S1 over lateral heels, within 31 days of SCI, accurately identified future independent walkers 1 year after SCI. Normal pinprick in both lateral heels provided good prognosis, any pinprick sensation in either lateral heel provided fair prognosis, and no sensation provided poor prognosis. This CPR performed satisfactorily in the middle SCI severity subgroup. CONCLUSIONS: In this large multi-site study, we derived and validated a simple, accurate CPR using only pinprick sensory testing at lateral heels that predicts future independent walking after SCI.

Hammersmith Infant Neurological Examination Subscores Are Predictive of Cerebral Palsy.

BACKGROUND: The Hammersmith Infant Neurological Examination (HINE) is a standardized assessment that identifies early signs of cerebral palsy (CP). In practice, the clinician performs this assessment in its entirety, yielding a global score. This study aimed to investigate the individual HINE subscores and "asymmetries" as predictive indicators of CP. METHODS: In this retrospective nested case-control study, a pediatric neurologist performed the HINE on a cohort of three- to four-month-old former neonatal intensive care unit infants. The infants' neurodevelopmental outcomes were determined by chart review when they were aged two to three years. We performed univariate and multivariable logistic regression analyses to yield the accuracy of the global HINE score, HINE subscores, and "asymmetries" in classifying infants with and without CP. RESULTS: Of the 108 infants on whom HINE was performed, 50 were either discharged due to normal developmental progress or were lost to follow-up. Of the remaining 58 subjects, 17 had CP and 41 did not. Receiver operator characteristic (ROC) curves of univariate models yielded the following area under the curve (AUC) scores: global HINE score (AUC = 0.75), "reflexes and reactions" (AUC = 0.80), "cranial nerve function" (AUC = 0.76), "asymmetries" (AUC = 0.75), and "movements" (AUC = 0.71). The ROC for our multivariable model (AUC = 0.91) surpassed the global HINE score's predictive value for CP. CONCLUSIONS: The weighted combination of HINE subscores and "asymmetries" outperforms the global HINE score in predicting CP. These findings suggest the need for revisiting HINE, but further validation with a larger dataset is required.

Performance of Large Language Models on a Neurology Board-Style Examination.

Importance: Recent advancements in large language models (LLMs) have shown potential in a wide array of applications, including health care. While LLMs showed heterogeneous results across specialized medical board examinations, the performance of these models in neurology board examinations remains unexplored. Objective: To assess the performance of LLMs on neurology board-style examinations. Design, Setting, and Participants: This cross-sectional study was conducted between May 17 and May 31, 2023. The evaluation utilized a question bank approved by the American Board of Psychiatry and Neurology and was validated with a small question cohort by the European Board for Neurology. All questions were categorized into lower-order (recall, understanding) and higher-order (apply, analyze, synthesize) questions based on the Bloom taxonomy for learning and assessment. Performance by LLM ChatGPT versions 3.5 (LLM 1) and 4 (LLM 2) was assessed in relation to overall scores, question type, and topics, along with the confidence level and reproducibility of answers. Main Outcomes and Measures: Overall percentage scores of 2 LLMs. Results: LLM 2 significantly outperformed LLM 1 by correctly answering 1662 of 1956 questions (85.0%) vs 1306 questions (66.8%) for LLM 1. Notably, LLM 2's performance was greater than the mean human score of 73.8%, effectively achieving near-passing and passing grades in the neurology board examination. LLM 2 outperformed human users in behavioral, cognitive, and psychological-related questions and demonstrated superior performance to LLM 1 in 6 categories. Both LLMs performed better on lower-order than higher-order questions, with LLM 2 excelling in both lower-order and higher-order questions. Both models consistently used confident language, even when providing incorrect answers. Reproducible answers of both LLMs were associated with a higher percentage of correct answers than inconsistent answers. Conclusions and Relevance: Despite the absence of neurology-specific training, LLM 2 demonstrated commendable performance, whereas LLM 1 performed slightly below the human average. While higher-order cognitive tasks were more challenging for both models, LLM 2's results were equivalent to passing grades in specialized neurology examinations. These findings suggest that LLMs could have significant applications in clinical neurology and health care with further refinements.

Performance of Empirical Mode Decomposition for Frequency Identification in SSVEP Based BCI.

Empirical mode decomposition based conventional correlation (EMDCC) method is proposed to identify the frequency components in steady state visual evoked potentials (SSVEP) in electroencephalogram(EEG).The main aim of the proposed EMDCC method is to recognise narrow band frequency components that are present in SSVEP. The study is evaluated on two datasets. The first one is a 40 target benchmark dataset obtained from 35 subjects and the second is a 4 class Inhouse dataset collected from 10 healthy participants. The mean detection accuracy of the conventional correlation method is 85.64 % for the benchmark dataset and it is improved to 93.79 % in the proposed method. The mean detection accuracy of the conventional correlation method is 67.5 % for the Inhouse dataset and it is increased to 82.5 % in the proposed method. The mean detection accuracy of the proposed EMDCC method is also compared to time-weighting canonical correlation analysis (TWCCA) for the benchmark dataset. The mean detection accuracy of TWCCA is 91.04 %. Hence the results show better detection accuracies in the proposed EMDCC method than the simple conventional correlation method and also the existing TWCCA method.

Experimental validation on dual-frequency outperforms single-frequency SSVEP with large numbers of targets within a given frequency range.

Multi-frequency steady-state visual evoked potential (SSVEP) aims to increase the number of targets in SSVEP-based brain-computer interfaces. However, the effectiveness of multi-frequency SSVEP when there is a large number of targets compared to traditional single-frequency SSVEP has not been demonstrated to date. It is also unclear the degree to which multi-frequency SSVEP outperforms single-frequency SSVEP as the number of targets increases. This study directly compares single-frequency and dual-frequency SSVEPs for different numbers of targets within a fixed (5 Hz) frequency range. Our results demonstrate that dual-frequency SSVEP maintains its performance at a high level of accuracy in the range while single-frequency SSVEP performance falls as the number of targets becomes very high within the given frequency range. In this particular study, dual-frequency SSVEP has a clear advantage when there are more than 120 targets in a 5 Hz frequency range.