Basic and Clinical Neuroscience最新文献

Introduction: Gait impairment is one of the consequences of cerebral palsy (CP) as a permanent neurological disorder. The therapy-induced neuroplasticity should be accompanied by functional improvement to have a persistent treatment effect. In this regard, we aimed to determine the correlation between brain functional activity changes and walking capacity improvement following treatments in children with hemiplegic CP (HCP).

Methods: Twenty-one spastic HCP children (7-12 years old) were randomly divided into 3 groups. Occupational therapy (OT) was performed for the first group. The second group received repetitive transcranial magnetic stimulation (rTMS) treatment, and the third group underwent anti-gravity treadmill (AlterG system) training. AlterG training and OT were provided for 45 minutes, and rTMS was applied for 20 minutes per session, 3 times per week for 8 weeks. Brain functional activity while executing passive tasks involving knee flexion/extension and ankle plantarflexion/dorsiflexion over the range of motion was quantified using functional magnetic resonance imaging (fMRI). Walking capacity was indexed by clinical measures. Clinical and fMRI evaluations were performed pre- and post-training.

Results: Our results indicate that intensive OT, rTMS, and AlterG training enhance brain functional activity and walking capacity in pediatrics with CP. Also, our results reveal a robust correlation between the corpus callosum (CC) functional activity changes and walking capacity improvement.

Conclusion: Regardless of the type of treatment, the improvement in gait function in children with CP may reflect an increase in brain functional activity in callosal neurons, which may reveal an increase in interhemispheric coupling.

Introduction: Aphasia is one of the most severe post-stroke deficits affecting speech, comprehension, reading, and writing modalities. In some patients, speech is severely impaired, so choosing an alternative or complementary approach for communication seems necessary. Writing has the closest characteristics to verbal language. So, it can be a substitute or facilitate speech and improve the quality of communication. Therefore, this study aimed to design a writing treatment protocol for Persian stroke patients and investigate its effect on improving communication skills.

Methods: First, the writing treatment protocol was designed by considering the characteristics of the Persian written language, and an expert panel determined its validity. Then, a single-subject study with ABA design was performed on 6 stroke patients suffering from chronic aphasia, non-fluent with limited speech. After the baseline phase, treatment sessions using the developed protocol were conducted for one hour twice weekly for 10 sessions. Finally, a follow-up was performed to evaluate the stability of the treatment.

Results: The results showed that patients' improvement was limited to trained words, which were treated using the developed protocol, and no generalization was observed for untrained words. The effect size indices (improvement rate difference, percentage of non-overlapping data, and percentage of overlapping data) showed the acceptable effect of treatment, its effectiveness, and the very high impact of writing therapy in all patients.

Conclusion: Writing treatment using the developed Persian protocol can improve patients' writing performance and communication. An essential outcome of this study is introducing a writing treatment approach as a new intervention for Persian patients with limited speech.

Introduction: Individuals with autism spectrum disorder (ASD) have impairments in emotion processing, including recognizing facial emotions. There is a significant need for medication to improve core symptoms of ASD. Bumetanide is one of the most recently used drugs in some studies of ASD to address this need. This study aimed to evaluate the effect of bumetanide on the brain response of youth with ASD while they were recognizing facial emotions using the event-related potentials (ERPs).

Methods: Fifteen children with ASD aged between 7 to 16 years were evaluated using the childhood autism rating scale (CARS), schedule for affective disorders and schizophrenia for school-age children-present and lifetime version, social responsiveness scale, Wechsler intelligence scale for children-revised form, and standard blood tests. The electrical brain response was measured while they were doing a facial emotion recognition task (FERT). After 3 months of treatment, they were assessed again regarding core symptoms and ERPs.

Results: The behavioral problems of the participants decreased significantly based on CARS. With regard to behavioral performance on FERT, the accuracy of detecting emotions increased, and reaction time decreased significantly. The amplitude of N170, EPN, and N250 increased, and latency for N170 and N250 decreased significantly in some electrodes. There were no serious side effects.

Conclusion: In this study, bumetanide improved behavioral symptoms and recognition of facial emotions. Also, brain function was improved based on the ERP components. So, bumetanide can be used safely in children and adolescents with ASD to improve the main symptoms of the disorder.

Introduction: Autism spectrum disorder (ASD) is a neurodevelopmental disorder. The pattern of eye movements during reading can significantly impact reading quality. This study aimed to examine the eye movement patterns, which are essential for reading, in children with ASD compared to their neurotypical peers.

Methods: This study focused on two crucial indicators influencing reading: Eye fixation time and saccade movement. A comparison of parameters of saccade movements and eye fixation in a sentence reading task was done between two groups using an eye tracker device. Autistic children (15 children, mean age: 102.33 months) and their neurotypical peers (17 children, mean age: 101.69 months) participated in this study.

Results: Compared to their neurotypical peers, children with ASD had lower amplitude while reading sentences (P=0.02). These children used more fixations to read the words in the sentence (P=0.02). Comparing the total time spent reading a sentence between the two groups shows that autistic children need more time to read a sentence (P=0.02).

Conclusion: These results suggest that low-level sensorimotor processes in generating accurate eye movements, such as the dorsal visual pathway and cerebellum, can significantly impact the reading quality of children with ASD.

Introduction: Glutamate plays a significant role in synaptic plasticity, which is important for learning and memory. Astrocytes are an important part of glial cells or neuroglia. They are involved in neuroinflammation and are key in maintaining glutamine/glutamate homeostasis. As astrocytes provide vital support to neurons in pathological conditions, we aimed to evaluate the effect of hippocampal astrocyte ablation induced by microinjection of L-α-aminoadipic acid (L-α-AAA) in this study. We intend to assess memory, anxiety, and the density of glial fibrillary acidic protein-immunoreactive (GFAP-ir) astrocytes in the hippocampus.

Methods: A total of 21 adult male Wistar rats were randomly assigned to control, vehicle, and experimental groups. L-α-AAA was injected into their hippocampal CA1 subfield for 3 days. Then, their memory was evaluated by an inhibitory passive avoidance test, and anxiety-related behavior using an elevated plus maze apparatus. Hippocampal sections were immunostained for GFAP, and the density of GFAP-ir astrocytes was evaluated.

Results: Microinjection of L-α-AAA into the CA1 subfield of the hippocampus significantly decreased the step-through latency time in the passive avoidance test, decreased time spent in the open arm, and increased time spent in the closed arm in the elevated plus maze test. Also, the administration of L-α-AAA significantly declined the density of GFAP-ir astrocytes in the hippocampus.

Conclusion: Inhibition of astrocytes impaired memory and increased anxiety-like behavior in male rats. Hence, the current study confirmed hippocampal astrocytes' key role in memory and anxiety-like behavior, which can be considered in future therapeutic strategies.

Introduction: The COVID-19 pandemic has increased psychological distress and impacted the diagnosis and treatment of noncommunicable diseases. This study aimed to examine the comparative effectiveness of emotionally focused therapy (EFT) and transcranial direct current stimulation (tDCS) on the anxiety and quality of life (QoL) in patients with coronary artery disease (CAD) during the COVID-19 pandemic.

Methods: A total of 45 participants who met the criteria for a current episode of CAD, referred to Shahid-Rajaee Heart Hospital in Tehran City, Iran, were chosen by convenience sampling method. They were randomly assigned to a 9-week/60-minute EFT (n=15) group therapy, a 5-week/20-minute tDCS (n=15) experimental group, and one control group (n=15). They were assessed at pre-test, post-test, and 3-month follow-up. The study subjects completed the self-reported reliable and valid Persian version of questionnaires, Beck anxiety inventory (BAI), and health-related quality of life (HRQOL). Then, repeated measures analysis of variance was used to measure inferential statistics.

Results: There were significant improvements in anxiety and QoL scores in both EFT and tDCS groups over the post-test and follow-up period (P≤0.01). However, a difference was found when EFT had a greater effect on the anxiety and QoL.

Conclusion: These results showed that EFT and tDCS have effective interventions in reducing anxiety and improving the QoL of CAD patients, but improvements with EFT were greater than those with tDCS.

Introduction: Mirror neurons' function is thought to be enhanced by emotion processing. There is some evidence that the valence of an emotional presentation (positive or negative) can influence subsequent mirror neuron activity differently. Additionally, mirror neurons are claimed to provide the mechanism necessary for the embodied simulation of others' mental states. Therefore, there is an assumption that relational emotion processing may manipulate mirror neuron functions.

Methods: Via transcranial magnetic stimulation (TMS) of the primary motor cortex (PMC) and electromyography recording from contralateral hand muscles, 20 participants viewed videos of either a static hand or a transitive hand action preceded by either neutral or general (negative and positive) and relational (negative and positive) images.

Results: Corticospinal excitability facilitation during action observation was significantly greater following the positive general than negative general emotion stimuli. Regarding relational emotions, we observed an increased mirror neuron system (MNS) activity following relational negative compared to relational positive, relational negative compared to general negative, and general positive compared to relational positive stimuli.

Conclusion: This finding supports the assumption that relational content interferes with mentalizing capacity.

Introduction: The study of brain functional networks in attention deficit hyperactivity disorder (ADHD) has provided useful information about the hyper- or hypo-connectivity between distinct brain regions. Nevertheless, the impact of negative links (antisynchrony) and their topology on the stability of the network still must be investigated.

Methods: In this study, we hypothesized that the effect of dysconnectivity and antisynchrony should mainly be local and may not influence the overall stability and flexibility of the network in ADHD. Therefore, differences in brain functional organization of ADHD individuals were compared to a typically developed group using the structural balance theory.

Results: Our results did not show any significant differences in the balance-energy of the resting-state network between healthy individuals and three subtypes of ADHD. However, a negative correlation was found between behavioral measures of ADHD and balance energy, highlighting that the higher disorder index may push the network to a less flexible (more balanced) state.

Conclusion: We hope these findings enhance our understanding of the systemic mechanism behind ADHD.

Introduction: Epilepsy is characterized by recurrent seizures associated with cognitive, mental, and social issues. Exercise has been well known as a non-pharmacological or complementary remedy that reduces the effective dose and side effects of pharmacological therapies. Orexin signaling pathway and brain-derived neurotrophic factor (BDNF) have an essential role in the pathogenesis of epilepsy. In this study, we investigated the effect of exercise on the modulation of the orexin-A (OXA) and BDNF signaling pathways in epileptic rats.

Methods: Male Wistar rats were divided into 5 groups: Normal saline (NS), seizure, physical activity (PA), PA + pentylenetetrazol (PTZ), and PA-PTZ. Assessment of seizure behaviors was done 30 min after each PTZ injection in the seizure, PA+PTZ, and PA-PTZ groups. Seizure behavior score (SBS) was monitored in seizure, PA+PTZ, and PA-PTZ. The expression of the OXA and BDNF in the CA1, CA3, and cortex was assayed by immunohistochemistry staining. The correlations between the OXA and BDNF were evaluated in the study groups.

Results: SBC was reduced in the epileptic rats that had exercised. Seizure and PA increased the OXA expression in the seizure and PA groups. Compared to the seizure group, the OXA expression decreased in the CA1 and CA3 of the PA+PTZ, PA-PTZ, and cortex of the PA+PTZ group. OXA was up-expressed in the PA-PTZ group compared to the PA+PTZ group. Seizure decreased the BDNF expression in the seizure group compared to the NS group. PA elevated the BDNF expression in the CA1, CA3, and cortex of the PA group. BDNF was up-expressed in the cortex of the PA+PTZ and the CA1, CA3, and cortex of PA-PTZ. BDNF expression increased in the CA1 and CA3 of the PA-PTZ compared to the PA+PTZ group. There was a significant correlation between the OXA and BDNF expression in the CA1, CA3, and cortex of the NS and seizure groups and the CA1 and cortex of the PA group.

Conclusion: Our results indicate that PA had an amelioration effect on the severity of the seizure. Our findings suggest that the effect of PA on seizure might not arise from the interaction of the OXA and BDNF expression in epileptic rats.

Introduction: Stress disorders have multidimensional effects. How we respond to these situations is different, depending on our individual differences and gender. Reports suggest that females are more susceptible to stress disorders compared to males in the same age group. The serotonin receptor system is an important mechanism involved in the regulation of stress and anxiety in males and females.

Methods: The current study incorporates a rodent model to study the sex-dependent role of serotonin receptors under chronic restrained stress conditions. A chronic restrained stress protocol was used to find the stress difference between male and female Sprague-Dawley (SD) rats. The molecular identification was done using quantitative real-time PCR and immunohistochemistry for serotonin 5HT-1B receptor in rat brains.

Results: Interestingly, the 5HT-1B receptor, one of the most important serotonin receptors, exhibits a sex-dependent difference in stress response in male and female rats. Most importantly, the trio partners (amygdala, hippocampus, and prefrontal cortex) exhibit a region-specific sex dependent difference in 5HT-1B receptor expression, which was correlated with the difference in the level of stress response. This biased serotonin 5HT-1B receptor function might be why females face more stress than males.

Conclusion: Overall, the results exhibit a sex-dependent difference for stress conditions in male and female rats, which was correlated with the spatial expression of the serotonin 5HT-1B receptor in the brain.