Search results for "cortex"

Repetitive TMS temporarily alters brain diffusion

2004

The authors investigated whether repetitive transcranial magnetic stimulation (rTMS) at 1 Hz (12 minutes; 90% of motor threshold) to the primary motor cortex (M1) leads to changes in diffusion-weighted imaging (DWI). After the rTMS train, there was a temporary small restriction in diffusion within the targeted left M1 that disappeared after 5 minutes. These findings provide a physiologic correlate to the reported behavioral consequences of off-line 1-Hz rTMS and reveal the transitory nature of the effects.

P27-S Sex differences and cortical excitability in healthy adolescents

2019

Background Sex is known to influence brain development. However, sex differences in cortical excitability and their relationship to motor functions is unclear. Aim We examined the sex related differences in the degree of handedness, left and right motor cortex excitability and manual dexterity. Methods 28 healthy adolescents (age 16–19 years,19 girls) were studied. The degree of right-handedness was determined by the Waterloo Handedness Questionnaire. Motor threshold (MT) of the abductor pollicis brevis was measured on both hemispheres. Box and block test (BBT) was used for manual dexterity. Independent samples t-test was used in statistical analysis. Results There were no differences betwe…

Translational Model of Cortical Premotor-Motor Networks.

2021

Abstract Deciphering the physiological patterns of motor network connectivity is a prerequisite to elucidate aberrant oscillatory transformations and elaborate robust translational models of movement disorders. In the proposed translational approach, we studied the connectivity between premotor (PMC) and primary motor cortex (M1) by recording high-density electroencephalography in humans and between caudal (CFA) and rostral forelimb (RFA) areas by recording multi-site extracellular activity in mice to obtain spectral power, functional and effective connectivity. We identified a significantly higher spectral power in β- and γ-bands in M1compared to PMC and similarly in mice CFA layers (L) 2/…

The frontal agranular cortex and the organization of purposeful movements

1985

A critical review of the traditional concepts of cortical association and motor areas is followed by a description of the functional organization and intrinsic and extrinsic cortical connectivity of the arcuate premotor area (APA). It is concluded that the frontal cortical organization of externally triggered purposeful movements is made possible by the associative character of Brodmann's area 6 and by its peculiar pattern of intra-areal connectivity.

2015

The execution of unilateral hand contractions before performance has been reported to produce behavioral aftereffects in various tasks. These effects have been regularly attributed to an induced shift in activation asymmetry to the contralateral hemisphere produced by the contractions. An alternative explanation proposes a generalized state of reduced bilateral cortical activity following unilateral hand contractions. The current experiment contrasted the above explanation models and tested the state of cortical activity after the termination of unilateral hand contractions. Twenty right-handed participants performed hand contractions in two blocks, one for each hand. Using electroencephalo…

Dissecting task-specific plasticity capacity in patients with multiple sclerosis with transcranial magnetic stimulation.

2020

Detecting nonlinear causal interactions between dynamical systems by non-uniform embedding of multiple time series.

2010

This study introduces a new approach for the detection of nonlinear Granger causality between dynamical systems. The approach is based on embedding the multivariate (MV) time series measured from the systems X and Y by means of a sequential, non-uniform procedure, and on using the corrected conditional entropy (CCE) as unpredictability measure. The causal coupling from X to Y is quantified as the relative decrease of CCE measured after allowing the series of X to enter the embedding procedure for the description of Y. The ability of the approach to quantify nonlinear causality is assessed on MV time series measured from simulated dynamical systems with unidirectional coupling (the Rössler-…

What effect can manual therapy have on a patient's pain experience?

2015

Manual therapy (MT) is a passive, skilled movement applied by clinicians that directly or indirectly targets a variety of anatomical structures or systems, which is utilized with the intent to create beneficial changes in some aspect of the patient pain experience. Collectively, the process of MT is grounded on clinical reasoning to enhance patient management for musculoskeletal pain by influencing factors from a multidimensional perspective that have potential to positively impact clinical outcomes. The influence of biomechanical, neurophysiological, psychological and nonspecific patient factors as treatment mediators and/or moderators provides additional information related to the proces…

Trait empathy modulates music-related functional connectivity

2021

It has been well established through behavioural studies that empathy significantly influences music perception. Such individual differences typically manifest as variability in whole brain functional connectivity patterns. To date, nobody has examined the modulatory effect of empathy on functional connectivity patterns during continuous music listening. In the present study, we seek to investigate the global and local connectivity patterns of 36 participants whose fMRI scanning was done by employing the naturalistic paradigm wherein they listened to a continuous piece of music. We used graph-based measures of functional connectivity to identify how cognitive and affective components of emp…

New fast mismatch negativity paradigm for determining the neural prerequisites for musical ability.

2011

Studies have consistently shown that the mismatch negativity (MMN) for different auditory features correlates with musical skills, and that this effect is more pronounced for stimuli integrated in complex musical contexts. Hence, the MMN can potentially be used for determining the development of auditory skills and musical expertise. MMN paradigms, however, are typically very long in duration, and far from sounding musical. Therefore, we developed a novel multi-feature MMN paradigm with 6 different deviant types integrated in a complex musical context of no more than 20 min in duration. We found significant MMNs for all 6 deviant types. Hence, this short objective measure can putatively be …