Temporal spectral evolution of pre-stimulus brain activity in visual and visuomotor tasks.

The aim of this study was to describe the spectral features of pre-stimulus event-related potential (ERP) components elicited in visual tasks such as the Bereitschaftspotential (BP), prefrontal negativity (pN) and visual negativity (vN). ERPs are considered time-locked and phase-locked (evoked) activity, but we have also analyzed the non-phase but time-locked (induced) activity in the same interval by applying the temporal spectral evolution (TSE) method. Participants (N = 26) were tested in a passive task, a simple response task (SRT) and a discriminative response task (DRT), where EEG activity was recorded with 64 scalp electrodes.

Analysis of Physical-Cognitive Tasks Including Feedback-Based Technology for Alzheimer's Disorder in a Randomized Experimental Pilot Study.

Introduction: Alzheimer's disease causes great changes, with the prefrontal cortex being the most frequently damaged zone; these changes affect physical and cognitive behavior and compromise autonomy.

Objective: The objective of this study was to evaluate the effects of physical-cognitive tasks on memory, attention, balance, gait, and risk of falling in Alzheimer's by using feedback-based technology.

Methods: Forty patients with Alzheimer's were recruited from an Alzheimer's Association; of these, 15 met the inclusion criteria and were included in the pilot RCT (eight in the control group; seven in the experimental group).

Effectiveness of feedback-based technology on physical and cognitive abilities in the elderly.

Aging raises a social and health challenge because the passing of time causes changes in cognitive and physical functions that impair functionality and quality of life. In addition, advancements in technology and information technology have led to the development of new techniques for retraining based on the feedback technology provides. To solve the negative consequences of aging, a randomized clinical trial was carried out to assess the effectiveness of a protocol using feedback-based technology to improve physical and cognitive functions in older adults.

Effect of the side of presentation in the visual field on phase-locked and nonphase-locked alpha and gamma responses.

Recent studies have suggested that nonphase-locked activity can reveal cognitive mechanisms that cannot be observed in phase-locked activity. In fact, we describe a concomitant decrease in nonphase-locked alpha activity (desynchronization) when stimuli were processed (alpha phase-locked modulation). This desynchronization may represent a reduction in "background activity" in the visual cortex that facilitates stimulus processing.

A systematic review of the application of machine-learning algorithms in multiple sclerosis.

Introduction: The applications of artificial intelligence, and in particular automatic learning or "machine learning" (ML), constitute both a challenge and a great opportunity in numerous scientific, technical, and clinical disciplines. Specific applications in the study of multiple sclerosis (MS) have been no exception, and constitute an area of increasing interest in recent years.

Objective: We present a systematic review of the application of ML algorithms in MS.

Attentional networks in neurodegenerative diseases: anatomical and functional evidence from the Attention Network Test.

Introduction: Understanding alterations to brain anatomy and cognitive function associated with neurodegenerative diseases remains a challenge for neuroscience today. In experimental neuroscience, several computerised tests have been developed to contribute to our understanding of neural networks involved in cognition. The Attention Network Test (ANT) enables us to measure the activity of 3 attentional networks (alertness, orienting, and executive function).

Deficits in Early Sensory and Cognitive Processing Are Related to Phase and Nonphase EEG Activity in Multiple Sclerosis Patients.

Currently, there is scarce knowledge about the relation between spectral bands modulations and the basis of cognitive impairment in multiple sclerosis (MS). In this sense, analyzing the evoked or phase activity can confirm results from traditional event-related potential (ERP) studies. However, studying the induced or nonphase activity may be necessary to elucidate hidden compensatory or affected cognitive mechanisms.

A systematic review of the application of machine-learning algorithms in multiple sclerosis.

Introduction: The applications of artificial intelligence, and in particular automatic learning or "machine learning" (ML), constitute both a challenge and a great opportunity in numerous scientific, technical, and clinical disciplines. Specific applications in the study of multiple sclerosis (MS) have been no exception, and constitute an area of increasing interest in recent years.

Objective: We present a systematic review of the application of ML algorithms in MS.

Altered phase and nonphase EEG activity expose impaired maintenance of a spatial-object attentional focus in multiple sclerosis patients.

Some of the anatomical and functional basis of cognitive impairment in multiple sclerosis (MS) currently remains unknown. In particular, there is scarce knowledge about modulations in induced EEG (nonphase activity) for diverse frequency bands related to attentional deficits in this pathology. The present study analyzes phase and nonphase alpha and gamma modulations in 26 remitting-relapsing multiple sclerosis patients during their participation in the attention network test compared with twenty-six healthy controls (HCs) matched in sociodemographic variables.

Reliability analysis of individual visual P1 and N1 maps indicates the heterogeneous topographies involved in early visual processing among human subjects.

There is a lack of studies regarding the reliability of the event-related components (ERPs) of an electroencephalogram (EEG) used to assess cognitive processing in human subjects. To explore the reliability scores for the P1 and N1 components in two sessions (separated by an average of 116 days), twenty subjects performed a visual lateralized detection paradigm and EEG recording (58 channels) were employed. The session factor did not modulate the P1/N1 latencies.

Individual test-retest reliability of evoked and induced alpha activity in human EEG data.

Diverse psychological mechanisms have been associated with modulations of different EEG frequencies. To the extent of our knowledge, there are few studies of the test-retest reliability of these modulations in the human brain. To assess evoked and induced alpha reliabilities related to cognitive processing, EEG data from twenty subjects were recorded in 58 derivations in two different sessions separated by 49.

Attentional networks in neurodegenerative diseases: anatomical and functional evidence from the Attention Network Test.

Introduction: Understanding alterations to brain anatomy and cognitive function associated with neurodegenerative diseases remains a challenge for neuroscience today. In experimental neuroscience, several computerised tests have been developed to contribute to our understanding of neural networks involved in cognition. The Attention Network Test (ANT) enables us to measure the activity of 3 attentional networks (alertness, orienting, and executive function).

[The Attention Network Test in the study of cognitive impairment of ADHD patients].

Introduction: The Attention Network Test (ANT) has been applied to the study of potential attentional impairments in diverse neuropathologies in the last years. This test allows analyzing of different networks involved in attentional processing (alerting, orientation and executive system).

Development: A specific application of ANT in ADHD patients shows that it is possible to find diverse impairments in the three attentional networks and even some studies revealed no alterations.

Multiple evoked and induced alpha modulations in a visual attention task: Latency, amplitude and topographical profiles.

Alpha event-related desynchronization (ERD) has been widely applied to understand the psychophysiological role of this band in cognition. In particular, a considerable number of publications have described spectral alterations in several pathologies using this time-frequency approach. However, ERD is not capable of specifically showing nonphase (induced) activity related to the presentation of stimuli.

Altered individual behavioral and EEG parameters are related to the EDSS score in relapsing-remitting multiple sclerosis patients.

Functional neuroanatomy of cognitive impairment in multiple sclerosis is currently still a challenge. During the progression of the disease, several cognitive mechanisms deteriorate thus diminishing the patient's quality of life. A primary objective in the cognitive assessment of multiple sclerosis (MS) patients is to find reliable measures utilizing diverse neuroimaging techniques.

Retest reliability of individual alpha ERD topography assessed by human electroencephalography.

Background: Despite the immense literature related to diverse human electroencephalographic (EEG) parameters, very few studies have focused on the reliability of these measures. Some of the most studied components (i.e.

Disentangling the attention network test: behavioral, event related potentials, and neural source analyses.

Background: The study of the attentional system remains a challenge for current neuroscience. The "Attention Network Test" (ANT) was designed to study simultaneously three different attentional networks (alerting, orienting, and executive) based in subtraction of different experimental conditions. However, some studies recommend caution with these calculations due to the interactions between the attentional networks.

Neural correlates of alerting and orienting impairment in multiple sclerosis patients.

Background: A considerable percentage of multiple sclerosis patients have attentional impairment, but understanding its neurophysiological basis remains a challenge. The Attention Network Test allows 3 attentional networks to be studied. Previous behavioural studies using this test have shown that the alerting network is impaired in multiple sclerosis.

EEG study on affective valence elicited by novel and familiar pictures using ERD/ERS and SVM-RFE.

EEG signals have been widely explored in emotional processing analyses, both in time and frequency domains. However, in such studies, habituation phenomenon is barely considered in the discrimination of different emotional responses. In this work, spectral features of the event-related potentials (ERPs) are studied by means of event-related desynchronization/synchronization computation.

Individual EEG differences in affective valence processing in women with low and high neuroticism.

Objective: In this study, individual differences in brain electrophysiology during positive and negative affective valence processing in women with different neuroticism scores are quantified.

Methods: Twenty-six women scoring high and low on neuroticism participated on this experiment. A support vector machine (SVM)-based classifier was applied on the EEG single trials elicited by high arousal pictures with negative and positive valence scores.

Retest reliability of individual p3 topography assessed by high density electroencephalography.

Background: Some controversy remains about the potential applicability of cognitive potentials for evaluating the cerebral activity associated with cognitive capacity. A fundamental requirement is that these neurophysiological parameters show a high level of stability over time. Previous studies have shown that the reliability of diverse parameters of the P3 component (latency and amplitude) ranges between moderate and high.

Cluster analysis of behavioural and event-related potentials during a contingent negative variation paradigm in remitting-relapsing and benign forms of multiple sclerosis.

Background: Event-related potentials (ERPs) may be used as a highly sensitive way of detecting subtle degrees of cognitive dysfunction. On the other hand, impairment of cognitive skills is increasingly recognised as a hallmark of patients suffering from multiple sclerosis (MS). We sought to determine the psychophysiological pattern of information processing among MS patients with the relapsing-remitting form of the disease and low physical disability considered as two subtypes: 'typical relapsing-remitting' (RRMS) and 'benign MS' (BMS).

[Attentional neural networks impairment in healthy aging].

Introduction: Diverse evidences have shown that the process of natural aging causes a decline in different cognitive functions, including among them the attentional process.

Aim: To determine how the healthy aging affects to the different attentional networks.

Subjects And Methods: Two groups: young subjects (32.

Sequential P3 effects in a Posner's spatial cueing paradigm: trial-by-trial learning of the predictive value of the cue.

The neurocognitive consequences of correct or incorrect spatial prediction in a sequential S1-S2 paradigm were assessed. Sequential dependence on previous trial outcome (valid or invalid) was assessed by late Event-Related Potentials (ERPs) and behavioral responses. Two different experiments were performed, situating the target in the vertical (Experiment 1) or in the horizontal (Experiment 2) meridian.

[Cognitive evoked potentials in remitting-relapsing and benign forms of multiple sclerosis].

Introduction: The assessment of the cognitive impairment in the multiple sclerosis disease is one of the most relevant challenges nowadays. An essential objective is to obtain diverse approaches that allow valuing objectively this impairment and its correlation with physiological variables.

Aim: To analyze the possible modulations in physiological components of the information processing (ERPs) related with an attentional deficit in diverse classes of patients with multiple sclerosis.