Alterations in brain white matter contributing to age-related slowing of task switching performance: The role of radial diffusivity and magnetization transfer ratio.

Successfully switching between tasks is critical in many daily activities. Age-related slowing of this switching behavior has been documented extensively, but the underlying neural mechanisms remain unclear. Here, we investigated the contribution of brain white matter changes associated with myelin alterations to age-related slowing of switching performance.

Subcortical volumetric changes across the adult lifespan: subregional thalamic atrophy accounts for age-related sensorimotor performance declines.

Even though declines in sensorimotor performance during healthy aging have been documented extensively, its underlying neural mechanisms remain unclear. Here, we explored whether age-related subcortical atrophy plays a role in sensorimotor performance declines, and particularly during bimanual manipulative performance (Purdue Pegboard Test). The thalamus, putamen, caudate and pallidum of 91 participants across the adult lifespan (ages 20-79 years) were automatically segmented.

Optimization of the transcranial magnetic stimulation protocol by defining a reliable estimate for corticospinal excitability.

The goal of this study was to optimize the transcranial magnetic stimulation (TMS) protocol for acquiring a reliable estimate of corticospinal excitability (CSE) using single-pulse TMS. Moreover, the minimal number of stimuli required to obtain a reliable estimate of CSE was investigated. In addition, the effect of two frequently used stimulation intensities [110% relative to the resting motor threshold (rMT) and 120% rMT] and gender was evaluated.

A single session of 1 mA anodal tDCS-supported motor training does not improve motor performance in patients with multiple sclerosis.

Purpose: To assess the effects of atDCS on motor performance in patients with multiple sclerosis (MS). Previously, anodal transcranial direct current stimulation (atDCS) has been shown to improve motor performance in healthy subjects and neurodegenerative populations. However, the effect of atDCS on motor performance is not examined in MS.

Anodal tDCS increases corticospinal output and projection strength in multiple sclerosis.

The application of anodal transcranial direct current stimulation (atDCS) to the human brain has been shown to elicit corticospinal (CS) excitability changes. This study evaluated the effect of a single session of atDCS on CS excitability in patients with multiple sclerosis (MS). atDCS and sham tDCS (stDCS) were applied to the primary motor cortex (M1) contralateral to the more severely impaired hand for 20min in a double-blinded crossover design.

Is motor learning mediated by tDCS intensity?

Although tDCS has been shown to improve motor learning, previous studies reported rather small effects. Since physiological effects of tDCS depend on intensity, the present study evaluated this parameter in order to enhance the effect of tDCS on skill acquisition. The effect of different stimulation intensities of anodal tDCS (atDCS) was investigated in a double blind, sham controlled crossover design.

Age-related differences in corticospinal excitability during a choice reaction time task.

Age-related declines in central processing may affect corticospinal (CS) excitability that underlies the emergence of voluntary responses to external stimuli. We used single-pulse transcranial magnetic stimulation (TMS) over the primary motor cortex to explore the evolution of CS excitability in 14 young and ten elderly healthy right-handed participants. Motor-evoked potentials (MEPs) were elicited in the right or left first dorsal interosseus (FDI) during the preparatory and premotor periods of a choice reaction time (CRT) task, which required selection of left or right index finger responses.

Active versus passive training of a complex bimanual task: is prescriptive proprioceptive information sufficient for inducing motor learning?

Perceptual processes play an important role in motor learning. While it is evident that visual information greatly contributes to learning new movements, much less is known about provision of prescriptive proprioceptive information. Here, we investigated whether passive (proprioceptively-based) movement training was comparable to active training for learning a new bimanual task.

Neuromuscular electrical stimulation as a possible means to prevent muscle tissue wasting in artificially ventilated and sedated patients in the intensive care unit: A pilot study.

Objective: The aim of this study was to explore if electrical stimulation could prevent muscle atrophy.

Material And Methods: Patients were hospitalized for postoperative coronary artery bypass graftin, chronic obstructive pulmonary disease, ventilatory failure, or acute cerebro-vascular accident, and were divided into an intervention group or a control group. The intervention group underwent daily 30 minute training with an intermittent neuromuscular electrical stimulation applied to the right quadriceps muscle.

Age-related differences in human corticospinal excitability during simple reaction time.

Age-related declines in central processing may delay the facilitation of corticospinal (CS) tracts that underlie emergence of voluntary responses to external stimuli. To explore this effect, single pulse transcranial magnetic stimulation (TMS) was applied to the left motor cortex at different latencies from the go-signal (auditory tone) during a simple reaction time (SRT) task with the right or left thumb [i.e.

The effect of long-term TENS on persistent neuroplastic changes in the human cerebral cortex.

The long-term effect of daily somatosensory stimulation with transcutaneous electrical nerve stimulation (TENS) on reorganization of the motor cortex was investigated in a group of neurologically intact humans. The scalp representation of the corticospinal projection to the finger (APB, ADM) and forearm (FCR, ECR) muscles was mapped by means of transcranial magnetic stimulation (TMS) before and after a 3-week intervention period, using map area and volume, and topographical overlaps between the cortical motor representations of these muscles as primary dependent measures. Findings revealed a significant increase in cortical motor representation of all four muscles for the TENS group from pre to posttest (all, P ≤ 0.

Long-term TENS treatment improves tactile sensitivity in MS patients.

Background: Transcutaneous electrical nerve stimulation (TENS) is commonly used in neurorehabilitation for the treatment of pain and spasticity.

Objective: The long-term effects of sensory stimulation by means of TENS on hand sensitivity were investigated in patients with multiple sclerosis (MS).

Methods: TENS was applied for 3 weeks (1 hour per day) on the median nerve region of the dominant hand.