Background: Sensory impairment has been related to age-associated cognitive decline. While these associations were investigated primarily in the auditory and visual domain, other senses such as touch have rarely been studied. Thus, it remains open whether these results are specific for particular sensory domains, or rather point to a fundamental role of sensory deficits in cognitive decline.
View Article and Find Full Text PDFBackground: Loss of sensorimotor stimulation and maladaptive plastic changes of the brain may play a major role in problematic aging phenomena such as frailty. However, it is not clear if interventions specifically targeting neuroplasticity can reverse or slow the development of frailty.
Objectives: We compared the effect of a tablet-based neuroplasticity-oriented sensorimotor training (experimental group, EG) and a tablet-based relaxation training (control group, CG) on frailty and sensorimotor brain function.
Although investigation of the brains of criminals began quite early in the history of psychophysiological research, little is known about brain plasticity of offenders with psychopathy. Building on our preliminary study reporting successful brain self-regulation using slow cortical potential (SCP) neurofeedback in offenders with psychopathy, we investigated the central nervous and autonomic peripheral changes occurring after brain self-regulation in a group of severe male offenders with psychopathy. Regarding the central nervous system, an overall suppression of the psychopathic overrepresentation of slow frequency bands was found, such as delta and theta band activity, after EEG neurofeedback.
View Article and Find Full Text PDFIntroduction: Dementia (particularly Alzheimer's disease, AD) is a major cause of impaired cognitive functions in the elderly. Amnestic mild cognitive impairment (aMCI) is a prodromal stage of AD, if substantiated by Alzheimer biomarkers. A neuroscientific model of pathological ageing emphasises the loss of brain plasticity, sensorimotor capacities and subsequent cognitive decline.
View Article and Find Full Text PDFDespite partial success, communication has remained impossible for persons suffering from complete motor paralysis but intact cognitive and emotional processing, a state called complete locked-in state (CLIS). Based on a motor learning theoretical context and on the failure of neuroelectric brain-computer interface (BCI) communication attempts in CLIS, we here report BCI communication using functional near-infrared spectroscopy (fNIRS) and an implicit attentional processing procedure. Four patients suffering from advanced amyotrophic lateral sclerosis (ALS)-two of them in permanent CLIS and two entering the CLIS without reliable means of communication-learned to answer personal questions with known answers and open questions all requiring a "yes" or "no" thought using frontocentral oxygenation changes measured with fNIRS.
View Article and Find Full Text PDFDopamine systems mediate key aspects of reward learning. Parkinson's disease (PD) represents a valuable model to study reward mechanisms because both the disease process and the anti-Parkinson medications influence dopamine neurotransmission. The aim of this pilot study was to investigate whether the level of levodopa differently modulates learning from positive and negative feedback and its electrophysiological correlate, the error related negativity (ERN), in PD.
View Article and Find Full Text PDFAmyotroph Lateral Scler Frontotemporal Degener
January 2017
Objective of this study was to evaluate attentional control mechanisms in amyotrophic lateral sclerosis (ALS) using an auditory event-related potentials (ERPs) paradigm. Fifteen mild to moderate ALS patients and 15 healthy controls were administered a brief neuropsychological test battery and an ERPs paradigm assessing selective attention. Four types of auditory stimuli were presented in random order: short standard (200 Hz, 200 ms), long standard (200 Hz, 500 ms), short deviant (1000 Hz, 200 ms) and long deviant (1000 Hz, 500 ms).
View Article and Find Full Text PDFEarly detection of movement intention could possibly minimize the delays in the activation of neuroprosthetic devices. As yet, single trial analysis using non-invasive approaches for understanding such movement preparation remains a challenging task. We studied the feasibility of predicting movement directions in self-paced upper limb center-out reaching tasks, i.
View Article and Find Full Text PDFA major clinical goal of brain-computer interfaces (BCIs) is to allow severely paralyzed patients to communicate their needs and thoughts during their everyday lives. Among others, P300-based BCIs, which resort to EEG measurements, have been successfully operated by people with severe neuromuscular disabilities. Besides reducing the number of stimuli repetitions needed to detect the P300, a current challenge in P300-based BCI research is the simplification of system's setup and maintenance by lowering the number N of recording channels.
View Article and Find Full Text PDFIn a proof-of-principle prototypical demonstration we describe a new type of brain-machine interface (BMI) paradigm for upper limb motor-training. The proposed technique allows a fast contingent and proportionally modulated stimulation of afferent proprioceptive and motor output neural pathways using operant learning. Continuous and immediate assisted-feedback of force proportional to rolandic rhythm oscillations during actual movements was employed and illustrated with a single case experiment.
View Article and Find Full Text PDFPatients in the completely locked-in state have no means of communication and they represent the target population for brain-computer interface research in the last 15 years. Although different paradigms have been tested and different physiological signals used, to date no sufficiently documented completely locked-in state patient was able to control a brain-computer interface over an extended time period. We introduce Pavlovian semantic conditioning to enable basic communication in completely locked-in state.
View Article and Find Full Text PDFDespite considerable growth in the field of brain-computer or brain-machine interface (BCI/BMI) research reflected in several hundred publications each year, little progress was made to enable patients in complete locked-in state (CLIS) to reliably communicate using their brain activity. Independent of the invasiveness of the BCI systems tested, no sustained direct brain control and communication was demonstrated in a patient in CLIS so far. This suggested a more fundamental theoretical problem of learning and attention in brain communication with BCI/BMI, formulated in the extinction-of-thought hypothesis.
View Article and Find Full Text PDFAmyotroph Lateral Scler Frontotemporal Degener
September 2013
Our objective was to investigate the relationship between brain-computer interface (BCI) communication skill and disease progression in amyotrophic lateral sclerosis (ALS). We sought also to assess stability of BCI communication performance over time and whether it is related to the progression of neurological impairment before entering the locked-in state. A three years follow-up, BCI evaluation in a group of ALS patients (n = 24) was conducted.
View Article and Find Full Text PDFBackground: Brain-computer interfaces (BCIs) allow people to control devices by translating brain signals into commands. BCIs represent a concrete solution with regard to communication and motor control disabilities of patients with amyotrophic lateral sclerosis (ALS). Most of the BCIs rely on visual interfaces in which patients must move their eyes to achieve efficient BCI control.
View Article and Find Full Text PDFWe investigated whether the covert orienting of visuospatial attention can be effectively used in a brain-computer interface guided by event-related potentials. Three visual interfaces were tested: one interface that activated voluntary orienting of visuospatial attention and two interfaces that elicited automatic orienting of visuospatial attention. We used two epoch classification procedures.
View Article and Find Full Text PDFFuture neuroprosthetic devices, in particular upper limb, will require decoding and executing not only the user's intended movement type, but also when the user intends to execute the movement. This work investigates the potential use of brain signals recorded non-invasively for detecting the time before a self-paced reaching movement is initiated which could contribute to the design of practical upper limb neuroprosthetics. In particular, we show the detection of self-paced reaching movement intention in single trials using the readiness potential, an electroencephalography (EEG) slow cortical potential (SCP) computed in a narrow frequency range (0.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 2012
The experimental findings herein reported are aimed at gaining a perspective on the complex neural events that follow lesions of the motor cortical areas. Cortical damage, whether by trauma or stroke, interferes with the flow of descending signals to the modular interneuronal structures of the spinal cord. These spinal modules subserve normal motor behaviors by activating groups of muscles as individual units (muscle synergies).
View Article and Find Full Text PDFThe paper presents some speculations on the loss of voluntary responses and operant learning in long-term paralysis in human patients and curarized rats. Based on a reformulation of the ideomotor thinking hypothesis already described in the 19th century, we present evidence that instrumentally learned responses and intentional cognitive processes extinguish as a consequence of long-term complete paralysis in patients with amyotrophic lateral sclerosis (ALS). Preliminary data collected with ALS patients during extended and complete paralysis suggest semantic classical conditioning of brain activity as the only remaining communication possibility in those states.
View Article and Find Full Text PDFBrain-computer interface (BCI) technology has been used for rehabilitation after stroke and there are a number of reports involving stroke patients in BCI-feedback training. Most publications have demonstrated the efficacy of BCI technology in post-stroke rehabilitation using output devices such as Functional Electrical Stimulation, robot, and orthosis. The aim of this review is to focus on the progress of BCI-based rehabilitation strategies and to underline future challenges.
View Article and Find Full Text PDFAim of this study is to investigate working memory functions in nondemented patients with amyotrophic lateral sclerosis (ALS) using neuropsychological testing and auditory event-related potentials. Twenty-four patients with ALS and 17 age- and education-matched controls underwent a comprehensive neuropsychological assessment, with particular emphasis on working memory functions. Event-related potentials were assessed with an active auditory oddball paradigm.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
November 2009
Production of voluntary movements relies critically on the functional integration of several motor cortical areas, such as the primary motor cortex, and the spinal circuitries. Surprisingly, after almost 40 years of research, how the motor cortices specify descending neural signals destined for the downstream interneurons and motoneurons has remained elusive. In light of the many recent experimental demonstrations that the motor system may coordinate muscle activations through a linear combination of muscle synergies, we hypothesize that the motor cortices may function to select and activate fixed muscle synergies specified by the spinal or brainstem networks.
View Article and Find Full Text PDFTo describe results of training and 1-year follow-up of brain-communication in a larger group of early and middle stage amyotrophic lateral sclerosis (ALS) patients using a P300-based brain-computer interface (BCI), and to investigate the relationship between clinical status, age and BCI performance. A group of 21 ALS patients were tested with a BCI-system using two-dimensional cursor movements. A four choice visual paradigm was employed to training and test the brain-communication abilities.
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