Modulation of the somatosensory blink reflex under fear.

OBJECTIVE: This study evaluated the isolated and combined effects of fear and PPS paradigms on SBR. METHOD: The prospective study was conducted with healthy participants. After stimulation of the right median nerve at the wrist, bilateral recordings were randomized under the following conditions: First experiment (with the right hand on the chair armrest): i. baseline recordings, ii. while watching fearful facial expressions from the Karolinska Emotional Faces battery (fear), iii. post-watching (post-fear), iv. while watching neutral facial expressions from the same battery (neutral), v. Immediately after viewing (post-neutral). Second experiment (right hand 2 cm away from the right eye, PPS): i. reference condition (PPS), ii. while watching fearful facial expressions (PPS-fear), iii. while watching neutral facial expressions (PPS-neutral). In each condition, SBR latency, area, duration, and amplitudes were measured and compared between conditions. RESULTS: We included 16 participants. SBR could be recorded in 11 (mean age:30.7 ± 5.2, F/M:5/6). First experiment: SBR amplitude was significantly reduced in fear condition (p = 0.008), and SBR area was reduced considerably in fear and post-fear conditions (p = 0.004) compared to the baseline. Second experiment: The SBR area was higher in the PPS (p = 0.009) compared to the baseline and even higher in the fearPPS compared to the PPS (p = 0.038). In neutral or PPS-neutral conditions, the area of the SBR did not change significantly. CONCLUSION: Fear suppressed SBR, but fear increased SBR when a threat stimulus was present. The findings were unrelated to habituation or attention, indicating cortical-amygdala-bulbar connections.

West Nile virus meningitis presenting with migrainous headache.

West Nile Virus (WNV) infection is a clinical picture that is transmitted from wild birds, its natural host, to humans through mosquitoes and generally shows an asymptomatic course. Influenza-like WNV fever is frequently seen in symptomatic individuals, and a neuroinvasive course is more rarely observed. Neuroinvasive WNV has a broad-spectrum profile of neurological signs and symptoms. WNV meningitis is one of the most common neuroinvasive forms of WNV, and it does not differ clinically and radiologically from other viral meningitis. Secondary headaches, which can mimic primary headaches, are an infectious factor that should be kept in mind in the etiology, especially in cases presenting in the summer months. In this study, a case of WNV meningitis presenting with a headache of migrainous character is presented.

Erdheim-Chester disease of brain parenchyma without any systemic involvement: A case report and review of literature.

Erdheim-Chester disease is a non-Langerhans cell histiocytosis syndrome characterised by histiocytic infiltration of different organs and systems in the body. Erdheim-Chester disease with isolated central nervous system (CNS) involvement causes diagnostic difficulties due to the absence of systemic findings and may result in misdiagnosis and inaccurate treatment choices. The case discussed in this report exemplifies how challenging it is to diagnose Erdheim-Chester disease with isolated CNS involvement. This case, which presented with progressive pyramidocerebellar syndrome, was clinically and radiologically resistant to all immunosuppressive and immunomodulatory treatments administered. The presence of false negative results in repeated histopathological investigations and the absence of evidence for systemic disease hindered the diagnosis and treatment work-up. In this study, we reviewed and discussed the prominent features of the presented case in light of the relevant literature.

Parainfectious autoimmune encephalitis related to SARS-CoV-2 infection, presenting with catatonia.

OBJECTIVE: SARS-CoV-2 infection commonly affects both the central and peripheral nervous systems, resulting in a variety of neurological and psychiatric symptoms. Whereas the effects of SARS-CoV-2 on neuronal structures in the short and long-term are still controversial, neurological involvement secondary to SARS-CoV- 2 is heterogeneous in terms of clinical presentation, treatment response, and prognosis. METHOD: A case of autoimmune encephalitis developing after SARS-CoV-2 is described in this article. RESULTS: The patient was admitted to the clinic with classical signs of catatonia and encephalopathy. The emergence of neuropsychiatric problems after the relief of SARS-CoV-2 symptoms suggests that symptoms were primarily related to immune processes. This patient demonstrated a good clinical response to symptomatic catatonia treatment and immune-modulatory agents and recovered both physically and cognitively without sequelae. CONCLUSION: SARS-CoV-2 infection may involve encephalitic involvement and psychological symptoms (including catatonia) after the infection by triggering autoimmune pathways.

A review of rheumatoid meningitis with case studies.

Rheumatoid arthritis (RA) is an autoimmune disease involving synovial joints, and it is known that extra-articular manifestations that may affect the central and peripheral nervous systems may develop during its course. Rheumatoid meningitis is very rare among all neurological involvements. In this study, cases diagnosed as rheumatoid meningitis with clinical, imaging, laboratory, and histopathological features are presented, and the aim of the study is to present current approaches in the diagnosis and treatment of rheumatoid meningitis in the light of case studies and current literature. The data of the patients who were followed up with the diagnosis of rheumatoid meningitis in neurology clinic between 2017 and 2021 were reviewed retrospectively. Three cases diagnosed with rheumatoid meningitis are presented in detail. In the first case, the diagnosis was reached by clinical, imaging, and laboratory findings as well as treatment response, while the diagnosis was made by histopathological verification in the second case. The third case shows that spontaneous remission can be observed in the course of rheumatoid meningitis. Rheumatoid meningitis, which is one of the rarest involvements in the course of RA, may present with headaches, focal neurological deficits, seizures, and altered consciousness. A meningeal biopsy is recommended when the differential diagnosis cannot be ruled out with imaging and laboratory findings. In the differential diagnosis Mucobacterium tuberculosis, syphilis, neuro-sarcoidosis, immunoglobulin G4-related disease, lymphoproliferative diseases, and systemic metastasis should be kept in mind. Aggressive RA management is recommended for treatment.

Ataxia in a Movement Disorders Outpatient Clinic: a Single-Center Experience in Turkey.

The etiology may not be determined in patients with ataxia despite detailed evaluations. The aim of this study was to investigate the clinical and laboratory characteristics of a large cohort of patients with adult-onset ataxia of different etiologies, particularly, undetermined etiologies despite extensive clinical, genetic, laboratory, electrophysiological, and imaging investigations. The medical records of all patients diagnosed with ataxia of subacute-chronic onset between January 2011 and March 2021 were reviewed retrospectively. The records of patients with symptom onset after 16 years of age were included in the study. In all patients, clinical and demographic findings were noted. Etiologies were classified as acquired, hereditary, degenerative (multiple system atrophy-cerebellar, MSA-C), functional, and undetermined. During the study period, we determined 74 patients with ataxia and 59 (35 males) patients met the study criteria. The age range was 22-87 years. The etiologies were hereditary (n = 19), acquired (n = 14), MSA-C (n = 9), functional (n = 2), and undetermined (n = 15). The patients with hereditary etiologies and undetermined causes were significantly younger at admission and at symptom onset (p = 0.001 and p = 0.000). There was a significant delay until diagnosis in patients with hereditary etiologies compared to other etiologies. In acquired etiologies, axial findings (71.4%) were more prominent whereas extremity and axial findings were more common in patients with hereditary etiologies (83.3%, p = 0.030). There were systemic and radiological indicators such as hearing loss, juvenile cataract, or dentate hyperintensity in certain disorders. Hereditary etiologies are as common as acquired or degenerative etiologies in adults. However, they have an earlier onset and delayed diagnosis. Therefore, we should recognize the extracerebellar neurological, systemic, and neuroimaging findings.

Cutaneous silent period in patients with spinal muscular atrophy type 2 and type 3.

OBJECTIVE: The aim of this study was to examine cutaneous silent periods (CSPs) in spinal muscular atrophy (SMA) type 2 and type 3 patients. METHODS: Fourteen patients with SMA and 14 healthy subjects were included. CSPs were recorded from thenar muscles after painful stimulation of the index finger during slight thumb abduction. CSP parameters (including onset latency, duration, index of suppression, long-loop reflex, and post-inhibitory rebound activity) were measured. All parameters were compared between SMA patients and healthy subjects using the Mann-Whitney U test. We then correlated CSP parameters to Hammersmith Functional Motor Scale Expanded (HFMSE) scores in SMA patients by Spearman-rho testing. RESULTS: No CSP parameter except E3% (i.e., the post-inhibitory rebound activity relative to pre-stimulus baseline) differed significantly between SMA patients and healthy subjects. E3% was significantly smaller in patients than healthy individuals. HFMSE scores of SMA patients correlated negatively with CSP duration and positively with E3%. DISCUSSION: Smaller E3%, correlating with longer CSP duration, in SMA patients with more severe clinical findings and therefore more marked motoneuron loss suggests that the E3 component following the CSP is directly affected by motoneuron loss.