Publications by authors named "Shapour Jaberzadeh"

This study aimed to investigate the corticospinal drive modulation to Agonist and Antagonist arm muscles following Strength training and detraining, as neural adaptations are critical for early strength gains. Seventeen healthy, untrained young adults underwent four weeks of unilateral dumbbell curl training (60-80% of one-repetition maximum) followed by four weeks of detraining. Transcranial magnetic stimulation (TMS) assessed corticospinal excitability and inhibition across multiple intensities (100-200% rMT).

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Background and PurposeParkinson's impairs movement control and proprioception. This pilot randomized controlled trial investigated whether anodal transcranial direct current stimulation (a-tDCS) combined with proprioceptive exercises improves these functions in people with Parkinson's.MethodsTwenty-four people with Parkinson's were randomly assigned (1:1) to either active a-tDCS (2mA, 20 minutes, 3 sessions/week for 2 weeks) or sham stimulation, followed by standardized proprioceptive training.

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The effects of 400 Hz anodal and cathodal transcranial pulsed current stimulation of the primary motor cortex (400 Hz a-tPCS, 400 Hz c-tPCS) on corticospinal excitability (CSE) and corticocortical excitability (CCE) and hand dexterity remain underexplored. This study examined the effects of a single session of 400 Hz a-tPCS, 400 Hz c-tPCS, and sham stimulation on CSE, CCE, and hand dexterity, providing insights for potential clinical applications in motor deficits. In this double-blinded, randomized, counterbalanced crossover trial, 26 healthy young adults completed three experimental sessions: 400 Hz a-tPCS, 400 Hz c-tPCS, and sham stimulation, spaced 48 h apart.

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To identify cognitive domains predictive of dynamic balance performance in older adults and inform targeted cognitive-motor interventions aimed at improving balance and reducing fall risk. This cross-sectional study used hierarchical multiple regression to analyze relationships between cognitive domains and dynamic balance among 62 community-dwelling older adults (≥65 years). Balance was assessed using the Y Balance Test (YBT) and Timed Up and Go Test (TUG), while cognitive function was measured using the Mini-Mental State Examination (global cognition), Stroop Test (inhibition), N-back Test (working memory), and Deary-Liewald Reaction Time Test (processing speed).

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The mechanism underlying transcranial pulsed current stimulation (tPCS) as a non-invasive neuromodulation technique has garnered considerable attention in recent years. However, the effects of anodal tPCS (a-tPCS) at low frequencies remain unexplored. This study aimed to investigate the a-tPCS effects at 0.

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Corticospinal excitability (CSE) is the responsiveness of the corticospinal and brain-to-muscle pathway, assessed using motor-evoked potentials (MEPs) via transcranial magnetic stimulation (TMS). It provides crucial insight into motor control, neuroplasticity, and neurological conditions. The use of TMS-induced MEPs in clinical and research contexts is contingent upon their intra- and intersession reliability.

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With the widespread adoption of smartphones, concerns about increased exposure to non-ionizing radiofrequency have emerged. This scoping review examines the effects of mobile phone exposure on neural oscillations and cortical excitability, focusing on both motor and non-motor regions of the cerebral cortex. A scoping review identified seventy-eight studies that involved healthy individuals and employed electroencephalography and only two studies that investigated transcranial magnetic stimulation as primary technical tools.

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Objective: To explore the possible association of balance and trunk extensor strength in chronic low back pain (CLBP) patients having tightened hamstring muscle.

Methods: In this correlational study, a total of forty-five patients with CLBP (mean age 38.80 ± 11.

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Repeated transcranial magnetic stimulation (rTMS) is a technique used to enhance motor learning in older adults. Some studies have shown that applying rTMS to the primary motor cortex (M1) and the cerebellum enhances motor learning. This study investigates the effects of M1 rTMS and cerebellar rTMS on motor learning in older adults.

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Background: Acupuncture is widely used in modulating brain excitability and motor function, as a form of complementary and alternative medicine. However, there is no existing meta-analysis evaluating the effectiveness and safety of acupuncture on corticospinal excitability (CSE), and the credibility of the evidence has yet to be quantified.

Objective: This study was designed to assess the efficacy and safety of electroacupuncture (EA) and manual acupuncture (MA) in enhancing brain excitability, specifically focusing on CSE as measured by transcranial magnetic stimulation (TMS).

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Transcranial direct current stimulation (tDCS) is an effective rehabilitation strategy that promotes motor learning. The related studies reported different findings through different modalities of tDCS over different brain regions. This study aimed to identify the optimal effects of tDCS on motor learning through a systematic review and network meta-analysis, focusing on determining the best electrode montage and assessing the efficacy of various tDCS configurations.

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Inconsistent results are observed in the effects of transcranial direct current stimulation (tDCS) with different montages on motor learning. This study aimed to compare the effects of anodal and cathodal tDCS (c-tDCS) over primary motor cortex (M1) at different intensities on motor learning in healthy young adults. The participants were randomly divided into: (1) 1 mA M1 c-tDCS, (2) 1 mA M1 anodal tDCS (a-tDCS), (3) 2 mA M1 c-tDCS, (4) 2 mA M1 a-tDCS and (5) M1 sham tDCS groups.

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Article Synopsis
  • Transcranial direct current stimulation (tDCS) shows promise for improving cognitive functions and treating cognitive disorders, but variable outcomes raise concerns about its safety and effectiveness due to unclear neural mechanisms.
  • The study investigates tDCS effects on macaque monkeys' cognitive abilities and neuron activity, revealing that tDCS reduced practice-related response slowdowns and altered neuron firing patterns compared to sham stimulation.
  • After tDCS, changes in behavior and neuron activity were observed to persist, indicating potential lasting effects, but tDCS did not significantly alter baseline neuron firing rates across multiple applications.
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Aim: The aging global population poses increasing challenges related to falls and dementia. Early identification of cognitive decline, particularly before noticeable symptoms manifest, is crucial for effective intervention. This review aims to determine the dynamic balance test most closely associated with executive function, potentially serving as a biomarker for cognitive decline.

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Considering the advantages of brain stimulation techniques in detecting the role of different areas of the brain in human sensorimotor behaviors, we used anodal transcranial direct-current stimulation (a-tDCS) over three different brain sites of the frontoparietal cortex (FPC) in healthy participants to elucidate the role of these three brain areas of the FPC on reaction time (RT) during a sequential visual isometric pinch task (SVIPT). We also aimed to assess if the stimulation of these cortical sites affects the transfer of learning during SVIPT. A total of 48 right-handed healthy participants were randomly assigned to one of the four a-tDCS groups: (1) left primary motor cortex (M1), (2) left dorsolateral prefrontal cortex (DLPFC), (3) left posterior parietal cortex (PPC), and (4) sham.

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Background: Impairment in both the motor and cognitive aspects of postural control is a critical issue in patients with chronic low back pain (CLBP) who experience high pain anxiety (HPA).

Objective: This study aimed to compare the effects of cathodal and anodal transcranial direct current stimulation (c-tDCS and a-tDCS) over the dorsolateral prefrontal cortex (DLPFC) on postural control during cognitive postural tasks in CLBP patients with HPA.

Methods: This study included 66 patients randomly assigned to three groups: DLPFC a-tDCS, DLPFC c-tDCS, and sham tDCS.

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The rating of perceived exertion (RPE) is a widely used method for monitoring the load during training, as it provides insight into the subjective intensity of effort experienced during exercises. Considering the role of brain in monitoring and perception of the effort, several studies explored the effect of transcranial direct current stimulation (tDCS) on RPE in different populations. The aim of current study is to review the studies that investigated the effect of tDCS on RPE in three groups including healthy untrained people, physically active persons, and athletes.

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Transcranial pulsed current stimulation (tPCS) is a noninvasive brain stimulation technique that has aroused considerable attention in recent years. This review aims to provide an overview of the existing literature on tPCS, examine the scope and nature of previous research, investigate its underlying mechanisms, and identify gaps in the literature. Searching online databases resulted in 36 published tPCS studies from inception until May 2023.

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The role of cognition in balance control suggests that mental fatigue may negatively affect balance. However, cognitive involvement in balance control varies with the type or difficulty of the balance task and age. Steady-state balance tasks, such as quiet standing, are well-learned tasks executed automatically through reflex activities controlled by the brainstem and spinal cord.

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Background: Various brain stimulation devices capable of generating high-frequency currents are readily available. However, our comprehension of the potential side or therapeutic effects associated with high-frequency transcranial pulsed current stimulation (tPCS), particularly concerning the new 400 Hz tPCS device, AscenZ-IV Stimulator, developed by AscenZion Neuromodulation Co. Pte.

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Objectives: To synthesise the literature on the efficacy of primary motor cortex anodal transcranial direct current stimulation (M1-a-tDCS), as a standalone or priming technique, for pain reduction in people with knee osteoarthritis (KOA).

Methods: The systematic literature search was conducted in MEDLINE, CINAHL, Embase and CENTRAL according to PRISMA statement.

Results: Fourteen studies involving 740 people with KOA were included.

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Many studies have shown that low back pain (LBP) is associated with psychosomatic symptoms which may lead to brain changes. This study aimed to investigate the effect of the concurrent application of cognitive behavioral therapy (CBT) and transcranial direct electrical stimulation (tDCS) over the left dorsolateral prefrontal cortex (DLPFC) on fear of pain, fear of movement, and disability in patients with nonspecific LBP. This study was performed on 45 LBP patients (23 women, 22 men; mean age 33.

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Purpose Of Review: This review aims to explore which cognitive domain is more closely associated with which type of balance (static or dynamic).

Resent Finding: Based on recent reviews, inhibitory control, a part of cognition, plays a crucial role in balance performance. Previous reviews report significant links between cognition, mobility, and physical function in older adults.

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Deficits in postural stability in response to environmental challenges are seen in chronic low back pain (CLBP) patients with high fear of pain (HFP). Hence, it is essential to follow effective approaches to treat postural stability deficits and improve the health status of these patients. The current study aimed to compare the effects of cathodal and anodal transcranial direct current stimulation (c-tDCS and a-tDCS) over the left dorsolateral prefrontal cortex (DLPFC) on postural stability in non-specific CLBP patients with HFP.

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Uni-hemispheric concurrent dual-site anodal transcranial direct current stimulation (UHCDS a-tDCS) of the primary motor cortex (M) and the dorsolateral prefrontal cortex (DLPFC) may enhance the efficacy of a-tDCS after stroke. However, the cellular and molecular mechanisms underlying its beneficial effects have not been defined. We aimed to investigate the effect of a-tDCS on brain metabolite concentrations (N-acetyl aspartate (NAA), choline (Cho)) in stroke patients using magnetic resonance spectroscopy (MRS).

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