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[ARTICLE] Comparison of the Efficacy of a Real-Time and Offline Associative Brain-Computer-Interface – Full Text

An associative brain-computer-interface (BCI) that correlates in time a peripherally generated afferent volley with the peak negativity (PN) of the movement related cortical potential (MRCP) induces plastic changes in the human motor cortex. However, in this associative BCI the movement timed to a cue is not detected in real time. Thus, possible changes in reaction time caused by factors such as attention shifts or fatigue will lead to a decreased accuracy, less pairings, and likely reduced plasticity. The aim of the current study was to compare the effectiveness of this associative BCI intervention on plasticity induction when the MRCP PN time is pre-determined from a training data set (BCIoffline), or detected online (BCIonline). Ten healthy participants completed both interventions in randomized order. The average detection accuracy for the BCIonline intervention was 71 ± 3% with 2.8 ± 0.7 min-1 false detections. For the BCIonline intervention the PN did not differ significantly between the training set and the actual intervention (t9 = 0.87, p = 0.41). The peak-to-peak motor evoked potentials (MEPs) were quantified prior to, immediately following, and 30 min after the cessation of each intervention. MEP results revealed a significant main effect of time, F(2,18) = 4.46, p = 0.027. The mean TA MEP amplitudes were significantly larger 30 min after (277 ± 72 μV) the BCI interventions compared to pre-intervention MEPs (233 ± 64 μV) regardless of intervention type and stimulation intensity (p = 0.029). These results provide further strong support for the associative nature of the associative BCI but also suggest that they likely differ to the associative long-term potentiation protocol they were modeled on in the exact sites of plasticity.

Introduction

Since Daly et al. (2009) proposed the possibility of a Brain-Computer-Interface (BCI) designed for neuromodulation of stroke patients, the field has rapidly expanded with numerous novel BCIs being introduced and tested in the clinic (Ang et al., 2010Broetz et al., 2010Cincotti et al., 2012Li et al., 2013Ramos-Murguialday et al., 2013Mukaino et al., 2014Young et al., 2014Pichiorri et al., 2015Mrachacz-Kersting et al., 2016). To date the main focus has been on upper limb rehabilitation with relatively few targeting lower limb function (for a review see, Teo and Chew, 2014Cervera et al., 2018). In addition, only one group has investigated patients in the sub-acute phases of stroke (Mrachacz-Kersting et al., 2017b), presumably due to the relatively stable condition that a chronic stroke patient presents. Effects from the use of a BCI are thus easier to control since patients in the acute and subacute phase are prone to spontaneous biological recovery (Krakauer and Marshall, 2015).

Typically, BCIs function by collecting the brain signals during a specific state such as performing a movement or motor imagery, extracting features of interest and then translating these into commands for external device control (Daly and Wolpaw, 2008). The available non-invasive BCIs for stroke patients have implemented both electroencephalography (EEG) or near-infrared spectroscopy (NIRS) to acquire the brain signals, extracted various spectral and temporal features [e.g., sensorimotor rhythm, movement related cortical potentials (MR)] and provided diverse types of afferent feedback to the patient such as those generated from using robotic devices, virtual reality or by driving direct nerve or muscular electrical stimulation (for review see, Cervera et al., 2018).

A vital component of any BCI designed for rehabilitation of lost motor function in stroke patients, is that the physiological theories behind learning and memory must be satisfied. One of the most influential theories was proposed in 1949 by Hebb (2005) from which we know that “Cells that fire together, wire together.” Although Hebb proposed his theory on theoretical grounds, animal data later verified that if the pre-synaptic neuron is activated simultaneously with the post-synaptic cell, plasticity is induced, often referred to as long-term potentiation (for a review see, Cooke and Bliss, 2006). In 2000, a group from Rostock University were the first to demonstrate long-term potentiation like plasticity in the intact human brain (Stefan, 2000) with later applications to lower limb muscles (Mrachacz-Kersting et al., 2007). In this intervention [paired associative stimulation (PAS)], a peripheral nerve that innervates the target muscle is activated using a single electrical stimulus and once the generated afferent volley has arrived at the motor cortex, a single non-invasive transcranial magnetic stimulus (TMS) is provided to that area of the motor cortex that has a direct connection to the target muscle (for a review see, Suppa et al., 2017).

In a modified version of PAS, the TMS stimulus has been replaced by the movement related cortical potential (MRCP) (Mrachacz-Kersting et al., 2012). The MRCP, that can be readily measured using EEG, is a slow negative potential that arises approximately 1–2 s prior to movement execution or imagination and attains its peak negativity at the time of movement execution (Walter et al., 1964). This intervention, also termed an associative BCI, induces significant plasticity of the cortical projections to the target muscle and leads to significant functional improvements in chronic and subacute stroke patients (Mrachacz-Kersting et al., 20162017b). In the first phase, patients are asked to attempt 30–50 movements (dorsiflexion of the foot), timed to a visual cue and they receive no sensory feedback. The time of the peak negativity (PN) of the resulting MRCP for every trial is extracted and an average calculated. During the second phase (the actual associative BCI intervention), this time is used to trigger the electrical stimulation of the target nerve such that the generated afferent volley arrives at the motor cortex at precisely peak negativity. Typically, 30–50 such pairings are performed over 3–12 sessions. Since the trigger of the electrical stimulator is not based on the online detection of the MRCP during the second phase, this intervention does not represent a BCI in the classical sense. In the current study the aim was to compare the effects of this associative BCI intervention on plasticity induction as quantified by the motor evoked potential (MEP) following TMS when the MRCP PN time is determined from the phase one trials (BCIoffline modus) or detected during the second phase by using the phase one trials as a training data set (BCIonline modus).[…]

 

Continue —> Frontiers | Comparison of the Efficacy of a Real-Time and Offline Associative Brain-Computer-Interface | Neuroscience

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[WEB SITE] Cognitive Assessment: Neurocognitive Assessment Battery Online for the detection of cognitive deterioration (CAB).

General Cognitive Assessment Battery (CAB)

Innovative online neuropsychological test. Study brain function and complete a comprehensive online screening. Precisely evaluate a wide range of abilities and detect cognitive well-being (high-moderate-low). Identify strengths and weaknesses in the areas of memory, concentration/attention, executive functions, planning, and coordination.

WHO IS IT FOR?

    • For my own evaluation
    • For a family member
    • For my patients
    • For my students
    • For a research study

TOTAL PRICE 49.95

 

Cognitive assessment battery to study brain function and cognitive performance

  • Assess current state of the user’s cognitive skills
  • For children 7 years and older and adults.
  • The complete battery lasts about 30-40 minutes.

The General Cognitive Assessment Battery (CAB) from CogniFit is a leading professional tool that makes it possible to get study the brain function of children 7 years and older and adults in depth, using online cognitive tasks. The results from this neuropsychological tool are useful for understanding the user’s cognitive state, strengths, and weaknesses. This can help determine whether or not the cognitive changes that the user may be experiencing are normal, or if they reflect some kind of neurological disorder. Any private or professional user can easily use this cognitive assessment.

This normalized cognitive test is completely online and lasts about 30-40 minutes. After completing the evaluation, a report will automatically be generated with the user’s neurocognitive profile. This report gathers useful information and presents data in an easy-to-understand format to make it possible to understand the functioning of different cognitive skills. It also provides valuable information that can help detect the risk of some disorder or problem, recognize its severity, and identify support strategies for each case.

We recommend using this neuropsychological assessment to better understand cognitive function, or cognitive, physical, psychological, or social well-being, and where there are symptoms or difficulties related o concentration/attention, memory, reasoning, planning, or coordination. We recommend using this complete cognitive test to complement a professional diagosis, and never to substitute a clinical consultation.[…]

 

Visit Site —> Cognitive Assessment: Neurocognitive Assessment Battery Online for the detection of cognitive deterioration (CAB).

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[ARTICLE] Review of the literature on the use of social media by people with traumatic brain injury (TBI)

Abstract

Purpose: To review the literature relating to use of social media by people with a traumatic brain injury (TBI), specifically its use for social engagement, information exchange or rehabilitation.

Method: A systematic review with a qualitative meta-synthesis of content themes was conducted. In June 2014, 10 databases were searched for relevant, peer-reviewed research studies in English that related to both TBI and social media.

Results: Sixteen studies met the inclusion criteria, with Facebook™ and Twitter™ being the most common social media represented in the included studies. Content analysis identified three major categories of meaning in relation to social media and TBI: (1) risks and benefits; (2) barriers and facilitators; and (3) purposes of use of social media. A greater emphasis was evident regarding potential risks and apparent barriers to social media use, with little focus on facilitators of successful use by people with TBI.

Conclusions: Research to date reveals a range of benefits to the use of social media by people with TBI however there is little empirical research investigating its use. Further research focusing on ways to remove the barriers and increase facilitators for the use of social media by people with TBI is needed.

Implications for Rehabilitation

  • Communication disabilities following traumatic brain injury (TBI) can be wide-ranging in scope and social isolation with loss of friendships after TBI is common. For many people, social media is rapidly becoming a usual part of everyday communication and its use has the potential to increase communication and social participation for people with TBI.
  • There is emerging evidence and commentary regarding the perceived benefits and risks, barriers and facilitators and purposes of use of social media within the TBI population.
  • Risks associated with using social media, and low accessibility of social media sites, form barriers to its use. Facilitators for social media use in people with TBI include training the person with TBI and their communication partners in ways to enjoy and use social media safely.
  • There is minimal rigorous evaluation of social media use by people with TBI and scant information regarding social media use by people with communication disabilities after TBI. Further investigation is needed into the potential benefits of social media use on communication, social participation and social support with the aim of reducing social isolation in people with TBI.

via Review of the literature on the use of social media by people with traumatic brain injury (TBI) – Disability and Rehabilitation –.

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