Andrés A González-Garrido

University of Guadalajara | UDG · Instituto de Neurociencias

Background: People diagnosed with substance use disorders (SUDs) are at risk for impairment of brain function and structure. However, physicians still do not have any clinical biomarker of brain impairment that helps diagnose or treat these patients when needed. The most common method to study these patients is the classical electroencephalographic...

The perception of time depends on the rhythmicity of internal and external synchronizers. One external synchronizer that affects time estimation is music. This study aimed to analyze the effects of musical tempi on EEG spectral dynamics during subsequent time estimation. Participants performed a time production task after (i) silence and (ii) liste...

Background. Sleep is an activation procedure and is considered the most potent and best-documented modulator of seizures and interictal epileptiform discharges (IEDs) on electroencephalogram (EEG). The precise role of sleep deprivation in the diagnostic process of epilepsy has not been fully clarified after more than 50 years of use. Sleep deprivat...

Fact retrieval deficits have been documented in children with mathematical learning disabilities. We assessed the retrieval of arithmetic facts in neurotypical 9-to-10-year-old children with different mathematical achievement levels using event-related potential methods while performing an arithmetic verification task (addition, subtraction, and mu...

Sex differences in cognition and their underlying brain mechanisms have attracted increasing attention. Brain electrical activity (EEG) represents a reliable, high-temporal resolution approach to assessing the neural correlates of ongoing cognitive activity. The aim of the present work was to provide a comprehensive review of the literature regardi...

Modulation of reflex responses is crucial to adapt our behavior and cognition, and this is especially difficult when biological relevant stimuli are present such as emotional faces. The aim of this study was to identify the effect of peripherally presented happy and angry facial expressions in reflexive saccades and saccadic inhibition/re-orientati...

The report of the electroencephalogram (EEG) results has traditionally been made using free-text formats with a huge variation in descriptions due to several factors. Recently, the International Federation of Clinical Neurophysiology (IFCN) endorsed the use of the Standardized Computer-based Organized Reporting of EEG (SCORE). This system has many...

Visuospatial working memory (VSWM) deficits have been demonstrated to occur during the development of type-1-diabetes (T1D). Despite confirming the early appearance of distinct task-related brain activation patterns in T1D patients compared to healthy controls, the effect of VSWM load on functional brain connectivity during task performance is stil...

Despite the recent literature on sex-related anatomic, maturational and functional brain differences, the study of significant individual developments in math learning and achievement has scarcely approached this perspective. We aimed to compare the influence of sex in functional brain connectivity and behavioral measures in a numerical comparison...

Challenges in early oral language acquisition in profoundly deaf individuals have an impact on cognitive neurodevelopment. This has led to the exploration of alternative sound perception methods involving training of vibrotactile discrimination of sounds within the language spectrum. In particular, stimulus duration plays an important role in lingu...

Brain-machine interfaces (BMIs) are useful tools for controlling assistive devices. One current approach in this field is continuous trajectory reconstruction (CTR), which decodes variables from electroencephalographic (EEG) signals. In this study, the CTR approach was applied to estimate kinetic variables from lower limb joints during pre-gait mov...

Working Memory (WM) deficits have been suggested as an endophenotypic marker for schizophrenia. This neurocognitive marker proposal has been supported by evidence of WM deficits also observed in unaffected high-risk relatives (HR) of patients with schizophrenia. Furthermore, empirical evidence suggests that working memory (WM) load and the implicit...

The infant brain tunes to acquire and understand the language in a prolonged and crucial process of vigorous neurodevelopment. Hence, early auditory deprivation may drastically affect this neurofunctional integration by compromising cognitive maturation and perceptual learning. Individuals with profound congenital deafness are impacted by sensory d...

Objective Type-1 diabetes (T1D) is a disruptive metabolic disease that has an impact on neurodevelopment through its effects on the structure and function of the brain. One of the cognitive domains affected by T1D is sustained attention. The aim of this study was to analyze this process in children with T1D and compare their results to those of hea...

This study examined Spanish spelling errors among 166 native Spanish-speaking students from Kindergarten to Grade 3 based on a spelling-to-diction task. Fifteen types of spelling errors were analyzed in a latent class analysis. Results suggested three phases of spellers: Phase 1 students had a high chance of committing almost all types of errors. P...

Resumen La esquizofrenia es considerada como un trastorno mental heterogéneo que abarca amplios rangos de expresión perceptiva, cognoscitiva, emocional, funcional, estructural y del comportamiento, que además se vincula a una importante susceptibilidad genética. Es por ello que investigar sobre esta enfermedad implique seleccionar cuidadosamente a...

Recent studies aiming to facilitate mathematical skill development in primary school children have explored the electrophysiological characteristics associated with different levels of arithmetic achievement. The present work introduces an alternative EEG signal characterization using graph metrics and, based on such features, a classification anal...

Background: Type 1 diabetes (T1D) is a metabolic disorder characterized by recurrent hypo- and hyperglycemic episodes, whose clinical development has been associated with cognitive and working memory (WM) deficits. Objective: To contrast quantitative electroencephalography (qEEG) measures between young patients with T1D and healthy controls whil...

The ability to modulate automatic responses, in order to favor voluntary actions is crucial for cognition and behavior, and this is particularly difficult when dealing with highly salient stimuli as emotional faces. The aim of this study was to evaluate the effects of angry faces on cortical activity during preparation of saccadic inhibition and vo...

Introduction: There is an essential relationship between reading development and orthographic knowledge, which varies depending on a language’s orthographic characteristics. In transparent orthographies, such as Spanish, that relationship is closer, where reading speed and orthographic knowledge reflect the automation of the process in which crucia...

The aim of this study was to compare a reconfigurable mobile electroencephalography (EEG) system (M-EMOTIV) based on the Emotiv Epoc ® (which has the ability to record up to 14 electrode sites in the 10/20 International System) and a commercial, clinical-grade EEG system (Neuronic MEDICID-05 ® ), and then validate the rationale and accuracy of reco...

El dominio del lenguaje escrito se basa en la consolidación de representaciones neurales complejas de los patro-nes ortográficos de las palabras. En virtud de explorar las características presentes en procesos neurales relaciona-dos con la especialización ortográfica, se estudiaron con métodos de imagen por resonancia magnética funcional los nivele...

The purpose of this study was to identify the effects of delayed response on inhibitory control in low- and high-impulsivity adolescents in the presence of an emotional context. Participants performed a Go/No-Go task in 4 conditions: a control context with and without delayed response, and a pleasant context with and without delayed response. The a...

Several executive functions decline with the development of type-1 diabetes (T1D), particularly working memory (WM). In adults, WM ensures efficient cognitive processing by focusing on task-relevant information while suppressing distractors. It has been well documented that WM can be influenced by emotional stimuli, which may facilitate the retenti...

Background Type 1 diabetes mellitus (T1D) affects the entire cellular network of the organism. Some patients develop cognitive disturbances due to the disease, but several authors have suggested that the brain develops compensatory mechanisms to minimize or prevent neuropsychological decline. The present study aimed to assess the effective connecti...

Este artículo no pretende realizar una revisión sistemática ni completa de la literatura, sino que tiene como objetivo ofrecer una visión crítica por parte de los autores, acerca de la organización funcional cerebral durante la lectura en personas bilingües. Primeramente se presenta un análisis crítico de diferentes propuestas teóricas acerca del p...

A close relationship between the performance on symbolic numerical comparison tasks and math achievements in children, adolescents, and young adults has been reiteratively reported. Moreover, several studies have consistently shown that children with math difficulties have an impaired ability to process numerical representations. In this context, w...

The development of neural substrates of spelling abilities is greatly influenced by the characteristics of the language. Orthographic consistency leads to the adoption of different reading strategies across languages. In this regard, it is crucial to understand the developing mechanisms underlying word recognition and reading fluency in a context i...

The aim of the study was to evaluate the neurofunctional effect of gender in Type‐1 Diabetes Mellitus (T1DM) patients during a Visual Spatial Working Memory (VSWM) task. The study included 28 participants with ages ranging from 17‐28 years. Fourteen well‐controlled T1DM patients (7 female) and 14 controls matched by age, sex, and education level we...

Motor imagery (MI)-based brain-machine interface (BMI) is a technology under development that actively modifies users’ perception and cognition through mental tasks, so as to decode their intentions from their neural oscillations, and thereby bringing some kind of activation. So far, MI as control task in BMIs has been seen as a skill that must be...

Symbolic numerical magnitude processing is crucial to arithmetic development, and it is thought to be supported by the functional activation of several brain-interconnected structures. In this context, EEG beta oscillations have been recently associated with attention and working memory processing that underlie math achievement. Due to that EEG coh...

Introduction The first rehabilitative intervention of a hearing impaired infant is hearing aid fitting. Functional gain is one of the most used measures in the verification of the prescribed parameters of hearing aids for evaluating their efficacy in achieving rehabilitation goals. This measure is defined as the relative decibel difference between...

Introduction The occlusion effect (OE) is a well known phenomenon in audiology clinical practice. It is often defined as the increase in sound pressure in front of the tympanic membrane for low frequencies through 1000 Hz, and the subsequent improvement in hearing sensitivity at these frequencies when a bone conducted signal is presented to the sku...

It has been generally accepted that skipping breakfast adversely affects cognition, mainly disturbing the attentional processes. However, the effects of short-term fasting upon brain functioning are still unclear. We aimed to evaluate the effect of skipping breakfast on cognitive processing by studying the electrical brain activity of young healthy...

The study of orthographic errors in a transparent language such as Spanish is an important topic in relation to writing acquisition because in Spanish it is common to write pseudohomophones as valid words. The main objective of the present study was to explore the possible differences in activation patterns in brain areas while processing pseudohom...

Orthographic competence allows automatic word recognition and reading fluency. To elucidate how the orthographic competence in Spanish-speaking adults might affect the neurofunctional mechanisms of visual word recognition, 32 young adults equally divided in two groups (HSS: High Spelling Skills, and LSS: Low Spelling Skills) were evaluated using fM...

Type 1 diabetes (T1D) is commonly diagnosed in childhood and adolescence, and the developing brain has to cope with its deleterious effects. Although brain adaptation to the disease may not result in evident cognitive dysfunction, the effects of T1D on neurodevelopment could alter the pattern of BOLD fMRI activation. The aim of this study was to ex...

Adolescents exhibit difficulties in behavioral regulation that become more evident when emotional contexts are involved, since these may hinder the development of socially-adaptive behaviors. The objectives of the present study were: to examine the influence of emotional contexts on adolescents’ ability to inhibit a prepotent response, evaluated by...

La existencia de una correlación entre la frecuencia cardíaca (FC), la frecuencia respiratoria (FR) y las respuestas electrodérmicas de la piel (Skin Conductance Response, SCR) ha sido reportada en la literatura, así como también el uso de estos parámetros como medida del nivel de activación del sistema nervioso autónomo. Objetivo: Este trabajo pre...

Early auditory deprivation has serious neurodevelopmental and cognitive repercussions largely derived from impoverished and delayed language acquisition. These conditions may be associated with early changes in brain connectivity. Vibrotactile stimulation is a sensory substitution method that allows perception and discrimination of sound and even s...

Children with mathematical difficulties usually have an impaired ability to process symbolic representations. Functional MRI methods have suggested that early frontoparietal connectivity can predict mathematic achievements; however, the study of brain connectivity during numerical processing remains unexplored. With the aim of evaluating this in ch...

Adolescents seem to act on the spur of the moment, with a behavior guided by emotions, especially the most impulsive ones. Delaying response could improve motor inhibition and, hence, help to avoid too rapid or unplanned responses. The purpose of this study was to measure the effect of the delay over inhibitory control when an irrelevant pleasant c...

The aim of the present study was to explore sex differences in the effects that emotional contexts exert on the temporal course of response inhibition using event-related potentials (ERP). Participants performed a Go-NoGo response inhibition task under 3 context conditions: with 1) neutral background stimuli, and 2) pleasant, and 3) unpleasant emot...

Está bien establecido que los problemas de multiplicación de un solo dígito se almacenan en memoria de largo plazo como una asociación fáctica de operación-resultado, lo que permite resolver problemas de manera automática, sin necesidad de ”operar” con los números. En la presente investigación se revisa la dificultad con la cual sujetos responden a...

Performance monitoring depends on cortical structures that are also activated in vicarious monitoring. While many experiments have shown that vicarious and on-line monitoring have a similar basis, most such experiments have focused on simple tasks. In order to assess the effect of non-contingent feedback on vicarious monitoring, 23 young volunteer...

Decision making has been found to be altered in suicide attempters, but little is known of their performance in social contexts. Twenty-seven depressed suicide attempters (DSA), 25 nonsuicidal depressed patients (DP), and 60 healthy participants (HC) were evaluated by a decision-making task in social context. Results indicated DSA and DP obtained l...

La dislexia es uno de los trastornos del desarrollo más comunes en la etapa escolar y afecta aproximadamente del 5 a 15% de la población. La comprensión en «tiempo real» de un texto requiere del procesamiento de la información visual entrante a través de una compleja serie de fijaciones cortas de la mirada y movimientos sacádicos de los ojos, así c...

Depression is a mental illness that presents alterations in brain connectivity in the Default Mode Network (DMN), the Affective Network (AN) and other cortical-limbic networks, and the Cognitive Control Network (CCN), among others. In recent years the interest in the possible effect of the different antidepressant treatments on functional connectiv...

Ictal and interictal epileptiform discharges affect brain functional dynamics, but the issue of how they occur is still under debate. The present study evaluated the brain electrical activity that underlies epileptic seizures by focusing analysis on four electroencephalographic time stages around seizure onset. The dynamics of the functional organi...

In recent years, increasing attention has been paid to the effects of Type 1 Diabetes (T1D) on cognitive functions. T1D onset usually occurs during childhood, so it is possible that the brain could be affected during neurodevelopment. We selected young patients of normal intelligence with T1D onset during neurodevelopment, no complications from dia...

Orthographic knowledge is affected by language processing, which is associated with word exposure. This study used event-related potentials (ERP) to explore this association in Spanish-speaking adults with different levels of orthographic competence (High Spelling Skills: HSS; Low Spelling Skills: LSS) while they performed a lexical decision task o...

The study of orthographic errors in a transparent language like Spanish is an important topic in relation to writing acquisition. The development of neuroimaging techniques, particularly functional magnetic resonance imaging (fMRI), has enabled the study of such relationships between brain areas. The main objective of the present study was to explo...

Feedback-related negativity (FRN) is a negative deflection that appears around 250 ms after the gain or loss of feedback to chosen alternatives in a gambling task in frontocentral regions following outcomes. Few studies have reported FRN enhancement in adolescents compared with adults in a gambling task without probabilistic reinforcement learning,...

In this paper we studied the functional neural substrates underlying the performance of homophonic spelling error detecting tasks including frequent and infrequent Spanish words- through functional Magnetic Resonance Imaging (fMRI) procedure in subjects with low orthographic performance. Method: A block design was used to administer 2 visual tasks,...

Processing and storage in visuospatial working memory (VSWM) seem to depend on attention-based mechanisms. In order to explore the effect of attention-attractive stimuli, such as emotional faces on VSWM performance, ERPs were obtained from 20 young adults while reproducing spatial sequences of six facial (happy and neutral) and non-facial control s...

Resumen: Introducción: La velocidad de denominación está estrechamente relacionada con la velocidad de la lectura y constituye un importante predictor del desempeño lector. Por otra parte, el déficit para recordar el orden en el que se presenta una secuencia de sonidos (juicio de orden temporal), se ha asociado con trastornos lectores, en particula...

Introducción: Las dificultades con el conocimiento ortográfico se consideran un problema extendido entre los jóvenes de habla española, pero no es clara la magnitud de tal problema, sus características o la relación que el pobre conocimiento ortográfico tiene con la lectura. Metodología: Se evaluó el conocimiento ortográfico de 827 estudiantes de b...