NeuroSci, Volume 4, Issue 3 (September 2023) – 6 articles

The aim of the present study was to investigate the deficits in timing reproduction in individuals with non-fluent aphasia after a left hemisphere lesion including the inferior frontal gyrus, in which Broca’s region is traditionally localised. Eighteen stroke patients with non-fluent aphasia and twenty-two healthy controls were recruited. We used a finger-tapping Test, which consisted of the synchronisation and the continuation phase with three fixed intervals (450 ms, 650 ms and 850 ms). Participants firstly had to tap simultaneously with the device’s auditory stimuli (clips) (synchronisation phase) and then continue their tapping in the same pace when the stimuli were absent (continuation phase). Patients with aphasia demonstrated less accuracy and greater variability during reproduction in both phases, compared to healthy participants. More specifically, in the continuation phase, individuals with aphasia reproduced longer intervals than the targets, whereas healthy participants displayed accelerated responses. Moreover, patients’ timing variability was greater in the absence of the auditory stimuli. This could possibly be attributed to deficient mental representation of intervals and not experiencing motor difficulties (due to left hemisphere stroke), as the two groups did not differ in tapping reproduction with either hand. Given that previous findings suggest a potential link between the IFG, timing and working memory, we argue that patients’ extra-linguistic cognitive impairments should be accounted for, as possible contributing factors to timing disturbances. Full article

Multiple sclerosis (MS) is an immune inflammatory disease that causes demyelination of the white matter of the central nervous system. It is generally accepted that the etiology of MS is multifactorial and believed to be a complex interplay between genetic susceptibility, environmental factors, and infectious agents. While the exact cause of MS is still unknown, increasing evidence suggests that disease development is the result of interactions between genetically susceptible individuals and the environment that lead to immune dysregulation and CNS inflammation. Genetic factors are not sufficient on their own to cause MS, and environmental factors such as viral infections, smoking, and vitamin D deficiency also play important roles in disease development. Several pathogens have been implicated in the etiology of MS, including Epstein–Barr virus, human herpesvirus 6, varicella-zoster virus, cytomegalovirus, Helicobacter pylori, Chlamydia pneumoniae, and Borrelia burgdorferi. Although vastly different, viruses and bacteria can manipulate host gene expression, causing immune dysregulation, myelin destruction, and neuroinflammation. This review emphasizes the pathogenic triggers that should be considered in MS progression. Full article

The effects of corticomuscular connectivity during object manipulation tasks with different haptic sensations have not been quantitatively investigated. Connectivity analyses enable the study of cortical effects and muscle responses during movements, revealing communication pathways between the brain and muscles. This study aims to examine the corticomuscular connectivity of three Electroencephalography (EEG) channels and five muscles during object manipulation tasks involving contact surfaces of Sandpaper, Suede, and Silk. The analyses included 12 healthy subjects performing tasks with their right hand. Power-Based Connectivity (PBC) and Mutual Information (MI) measures were utilized to evaluate significant differences in connectivity between contact surfaces, EEG channels, muscles, and frequency bands. The research yielded the following findings: Suede contact surface exhibited higher connectivity; Mu and Gamma frequency bands exerted greater influence; significant connectivity was observed between the three EEG channels ($C3$, $Cz$, $C4$) and the Anterior Deltoid (AD) and Brachioradialis (B) muscles; and connectivity was primarily involved during active movement in the AD muscle compared to the resting state. These findings suggest potential implementation in motor rehabilitation for more complex movements using novel alternative training systems with high effectiveness. Full article

Background: Low back pain (LBP) has been shown to have various biological, psychological, and social factors that affect prognosis. However, it is unclear how personality may influence self-reported outcome measures and therapeutic alliance (TA). Methods: Eysenck’s personality inventory was used to assess personality, while the numeric pain rating scale (NPRS), Oswestry Disability Index (ODI), Tampa Scale of Kinesiophobia (TSK), Global Rating of Change (GROC), and the Working Alliance Inventory (WAI) measured patient progress and relationship strength. All outcome measures were formulated in a single survey that both the therapist and patient completed electronically. Results: Sixty-seven patients with LBP and twenty-two licensed physical therapists participated. For personality measures, there was a significant positive correlation between neuroticism and GROC (rho = 0.295, p = 0.015) and a significant negative correlation between extraversion and WAI (rho = −0.243, p = 0.048). Significant correlations were found between ODI and TSK (rho = 0.462, p ≤ 0.001) and between ODI and GROC (rho = −0.416, p ≤ 0.001). A significant negative correlation was found between TSK and GROC (rho = −0.301, p = 0.013). Conclusions: Patients with higher levels of disability seemed to report higher levels of kinesiophobia and less overall improvement in physical therapy. Patients classified as neurotic reported higher levels of improvement while extraverted patients demonstrated a weaker therapeutic alliance with their therapist. Full article

Autism in humans is a lifelong behavioral disorder that typically manifests in early infancy, primarily affecting boys. It arises from neurodevelopmental changes that significantly impact social behavior, with the cerebellum being one of the principal affected regions. In this study, we investigated the cerebellum in an autism animal model, recording the multiunit activity of cerebellar vermis lobules 6 and 7 (L6 and L7) in male rats with autism-like behavior induced by postnatal valproate treatment. Two groups were formed: control (Ctrl) and experimental (VPA) males, which were further divided based on their living conditions into standard (Std) or enriched environments (EE). Social arenas were used for recording purposes. Both groups and lobules showed increased multiunit amplitude during social interaction (SI) and vertical exploration (VE), with higher amplitudes observed in VPA males. Interestingly, the EE significantly reduced the amplitude during SI, suggesting that EE promotes neural plasticity, resulting in improved social responses with fewer activated neurons, meaning improved activity with less energy consumption. Consequently, EE proves to be a valuable strategy for addressing the challenges associated with autism behavior. Full article

Despite the available literature on traumatic brain injury (TBI) biomarkers elsewhere, data are limited or non-existent in sub-Saharan Africa (SSA). The aim of the study was to analyse associations in acute TBI between the admission serum biomarker concentrations and TBI severity, CT-scan findings, and outcome, as well as to explore the influence of concurrent Toxoplasma gondii infection. The concentrations of serum biomarkers (GFAP, NFL Tau, UCH-L1, and S100B) were measured and Toxoplasma gondii were detected in the samples obtained <24 h post injury. GOSE was used to evaluate the 6-month outcome. All of the biomarker levels increased with the severity of TBI, but this increase was significant only for NFL (p = 0.01). The GFAP values significantly increased (p = 0.026) in those with an unfavourable outcome. The Tau levels were higher in those who died (p = 0.017). GFAP and NFL were sensitive to CT-scan pathology (p values of 0.004 and 0.002, respectively). The S100B levels were higher (p < 0.001) in TBI patients seropositive to Toxoplasma gondii. In conclusion, NFL was found to be sensitive to TBI severity, while NFL and GFAP were predictive of CT intracranial abnormalities. Increased levels of GFAP and Tau were associated with poorer outcomes 6 months after TBI, and the S100B levels were significantly affected by concurrent T. gondii infection in TBI patients compared with the seronegative patients. Full article