Publications by authors named "Lourdes Diaz-Comas"

The sensorimotor rhythm (SMR) is an electroencephalographic rhythm associated with motor and cognitive development observed in the central brain regions during wakefulness in the absence of movement, and it reacts contralaterally to generalized and hemibody movements. The purpose of this work was to characterize the SMR of 4-month-old infants, born either healthy at term or prematurely with periventricular leukomalacia (PVL). Two groups of infants were formed: healthy and premature with PVL.

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Children with learning disabilities (LD) frequently have an EEG characterized by an excess of theta and a deficit of alpha activities. NFB using an auditory stimulus as reinforcer has proven to be a useful tool to treat LD children by positively reinforcing decreases of the theta/alpha ratio. The aim of the present study was to optimize the NFB procedure by comparing the efficacy of visual (with eyes open) versus auditory (with eyes closed) reinforcers.

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Introduction: Studies of neuroplasticity have shown that the brain's neural networks change in the absence of sensory input such as hearing or vision. However, little is known about what happens when both sensory modalities are lost (deaf-blindness). Hence, this study of cortical reorganization in visually-impaired child cochlear implant (CI) candidates.

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In normal elderly subjects, the best electroencephalogram (EEG)-based predictor of cognitive impairment is theta EEG activity abnormally high for their age. The goal of this work was to explore the effectiveness of a neurofeedback (NFB) protocol in reducing theta EEG activity in normal elderly subjects who present abnormally high theta absolute power (AP). Fourteen subjects were randomly assigned to either the experimental group or the control group; the experimental group received a reward (tone of 1000 Hz) when the theta AP was reduced, and the control group received a placebo treatment, a random administration of the same tone.

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The objective of this work was to explore Neurofeedback (NFB) effects on EEG current sources in Learning Disabled (LD) children, and to corroborate its beneficial consequences on behavioral and cognitive performance. NFB was given in twenty 30-min sessions to 11 LD children to reduce their abnormally high theta/alpha ratios (Experimental Group). Another five LD children with the same characteristics received a placebo treatment (Control Group).

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The EEG of 10 normal male young adults was recorded during the performance of three different tasks: mental calculation, verbal working memory (VWM) and spatial working memory (SWM). The stimuli used in the three tasks were the same, only the instructions to the subjects were different. Narrow band analysis of the EEG and distributed sources for each EEG frequency were calculated using variable resolution electromagnetic tomography (VARETA).

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This study explores visual event-related potentials components in a group of poor readers (PRs) and control children who carried out figure and word categorization tasks. In both tasks, every child had to categorize between animal and non-animal stimuli in an odd-ball GO-GO paradigm. During the word categorization task, PRs presented longer reaction times, a poorer performance, longer and larger P2 amplitudes, and smaller amplitudes and longer P300 latencies than controls.

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In addition to their deficit in overt face recognition, patients with prosopagnosia also have difficulties in matching sequentially presented unfamiliar faces. Here we assessed the possibility that covert matching of faces was present in a case with prosopagnosia using event-related potentials (ERPs). The participants (patient FE and normal controls) were challenged with a face-identity matching task, in which they decided whether two sequentially presented photographs of unfamiliar faces represented the same person.

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