Vicente Molina

• Ph D
• Professor at University of Valladolid

Transcranial magnetic stimulation and electroencephalography (TMS-EEG) recordings are crucial to directly assess cortical excitability and inhibition in a non-invasive and task-free manner. TMS-EEG signals are characterized by TMS-evoked potentials (TEPs), which are employed to evaluate cortical function. Nonetheless, different time windows (TW) ha...

Background and Hypothesis Corollary discharge mechanism suppresses the conscious auditory sensory perception of self-generated speech and attenuates electrophysiological markers such as the auditory N1 Event-Related Potential (ERP) during Electroencephalographic (EEG) recordings. This phenomenon contributes to self-identification and seems to be al...

As we speak, corollary discharge mechanisms suppress the auditory conscious perception of the self-generated voice in healthy subjects. This suppression has been associated with the attenuation of the auditory N1 component. To analyse this corollary discharge phenomenon (agency and ownership), we registered the event-related potentials of 42 health...

As we speak, corollary discharge mechanisms suppress the auditory conscious perception of the self-generated voice in healthy subjects. This suppression has been associated with the attenuation of the auditory N1 component. To analyze this corollary discharge phenomenon (agency and ownership), we registered the Event-Related Potentials of forty-two...

As we speak, corollary discharge mechanisms suppress the auditory cortical response to the sensory perception of the self-generated voice in healthy subjects. This suppression has been associated with the attenuation of the auditory N1 component. To analyze this corollary discharge phenomenon (agency and ownership), we registered the Event-Related...

Aiming at discerning potential biotypes within the psychotic syndrome, we have recently reported the possible existence of two clusters or biotypes across schizophrenia and bipolar disorder characterized by their cognitive performance using the Brief Assessment of Cognition in Schizophrenia (BACS) instrument and validated with independent biologica...

The CACNA1C and the ZNF804A genes are among the most relevant schizophrenia GWAS findings. Recent evidence shows that the interaction of these genes with the schizophrenia diagnosis modulates brain functional response to a verbal fluency task. To better understand how these genes might influence the risk for schizophrenia, we aimed to study the int...

The KCNH2 gene, encoding for a subunit of a voltage-gated potassium channel, has been identified as a key element of neuronal excitability and a promising novel therapeutic target for schizophrenia (SZ). Nonetheless, evidence highlighting the role of KCNH2 on cognitive and brain activity phenotypes comes mainly from studies based on healthy control...

Anomalous self-experiences (ASEs) in schizophrenia have been under research for the last 20 years. However, no neuroimage studies have provided insight of the possible biological underpinning of ASEs. In this novel approach, the connectivity within the default mode network, calculated through a ROI-based analysis of functional magnetic resonance im...

Objective. Schizophrenia is a psychiatric disorder that has been shown to disturb the dynamic top-down processing of sensory information. Various imaging techniques have revealed abnormalities in brain activity associated with this disorder, both locally and between cerebral regions. However, there is increasing interest in investigating dynamic ne...

There is some consistency in previous EEG findings that patients with schizophrenia have increased resting-state cortical activity. Furthermore, in previous work, we have provided evidence that there is a deficit in the modulation of bioelectrical activity during the performance of a P300 task in schizophrenia. Our hypothesis here is that a basal h...

Introduction Recent studies support the identification of valid subtypes within schizophrenia and bipolar disorder using cluster analysis. Our aim was to identify meaningful biotypes of psychosis based on network properties of the electroencephalogram. We hypothesized that these parameters would be more altered in a subgroup of patients also charac...

Background and objectives Higher mental functions depend on global functional coordination of the brain. Our aim was to study the baseline condition and modulation of functional networks in a previously unevaluated clinical population, compare the results with a population from another country, and analyze their relationship with cognitive function...

Anomalous self-experiences (ASEs) are prevalent in schizophrenia, but its underpinnings are not completely understood. Given the likely complex substrate of the experience of the self, neurocognitive functions requiring coordinate cerebral activity may relate to ASEs. Moreover, cognitive deficits functioning may be involved in the link between self...

Mapping of Event-Related Potentials (ERP) associated with auditory and visual odd-ball paradigms has shown consistent differences between healthy controls and schizophrenia patients. It may be hypothesized that higher task attentional/cognitive demand will result in larger differences in these paradigms, which may help understanding the substrates...

Aims: This study has two main objectives: to describe the prevalence of undetected chronic obstructive pulmonary disease (COPD) in a clinical sample of smokers with severe mental illness (SMI), and to assess the value of the TIMER tool, which informs smokers of their respiratory risk and uses brief text messages to reinforce intervention. Method:...

Background and Objectives “Noise power” (NP) is a measure that allows the assessment of the fast-firing synchronization of neural oscillations. We aimed to replicate higher gamma NP values in frontal and midline regions in patients with schizophrenia and re-evaluate its specificity to this disorder. We also aimed to assess the relationship of highe...

A deficit in task-related functional connectivity modulation from electroencephalogram (EEG) has been described in schizophrenia. The use of measures of neuronal connectivity as an intermediate phenotype may allow identifying genetic factors involved in these deficits, and therefore, establishing underlying pathophysiological mechanisms. Genes invo...

Background: The synchronized activity of distributed neural assemblies — reflected in the electroencephalogram (EEG) — underpins mental function. In schizophrenia, modulation deficits of EEG spectral content during a P300 task have been replicated. The effects of treatment, chronicity and specificity in these deficits and their possible relationsh...

The identification of the cerebral substrates of psychoses such as schizophrenia and bipolar disorder is likely hampered by its biological heterogeneity, which may contribute to the low replication of results in the field. In this study we aimed to replicate in a completely new sample and supplement the results of a previous study with additional d...

The application of graph theory measures in the study of functional brain networks allows for the description of their general properties and their alterations in mental illness. Among these measures, connectivity strength (CS) estimates the degree of functional connectivity of the whole network. Previous studies in schizophrenia patients have repo...

Introduction International studies on clozapine use usually show lower than expected prescription proportions, under-dosing and delayed initiation of treatment, which has led to a number of initiatives aimed at improving its use and reducing the striking variability observed among practitioners. There are no similar studies on the Spanish populatio...

Background The study of cerebral underpinnings of schizophrenia may benefit from the high temporal resolution of electromagnetic techniques, but its spatial resolution is low. However, source imaging approaches such as low-resolution brain electromagnetic tomography (LORETA) allow for an acceptable compromise between spatial and temporal resolution...

Social cognition deficits are found in schizophrenia and bipolar disorder, but its neural underpinnings are poorly understood. Given the complexity of psychological functions underlying this kind of cognition, we hypothesized that alterations in global structural connectivity could contribute to those deficits. To test this hypothesis, we studied a...

Previous studies based on graph theory parameters applied to diffusion tensor imaging support an alteration of the global properties of structural connectivity network in schizophrenia. However, the specificity of this alteration and its possible relation with chronicity and treatment have received small attention. We have assessed small-world (SW)...

The study of the mechanisms involved in cognition is of paramount importance for the understanding of the neurobiological substrates in psychiatric disorders. Hence, this research is aimed at exploring the brain network dynamics during a cognitive task. Specifically, we analyze the predictive capability of the pre-stimulus theta activity to ascerta...

The present work studies the possible relation of parkinsonism and fronto-caudate dysconnectivity, as well as its relation to cognition in schizophrenia patients. We assessed parkinsonism using Simpson-Angus scale and prefronto-caudate connectivity using diffusion magnetic resonance in 22 schizophrenia patients (11 first-episodes) and 14 healthy co...

Our aim was to assess structural and functional networks in schizophrenia patients; and the possible prediction of the latter based on the former. The possible dependence of functional network properties on structural alterations has not been analyzed in schizophrenia. We applied averaged path‐length (PL), clustering coefficient, and density (D) me...

Background Social cognition impairments are found in schizophrenia patients and hamper their ability to form social relationships. The biological underpinnings of this social cognition impairment are poorly investigated. We hypothesize that structural disconnectivity, which is replicated in schizophrenia, might has a relevant role in social cogniti...

Background The rs3800779 polymorphism at KCNH2 gene, which encodes for a Voltage-Gated Potassium Channel Subunit, has been associated with the risk for schizophrenia (SZ) and with changes in the expression of a brain isoform with specific electrophysiological characteristics (Huffaker et al., 2009). It has been hypothesized that the KCNH2 gene vari...

Background Childhood trauma has been proposed as a risk factor for schizophrenia. Moreover, it has been related to brain abnormalities associated with cognitive functions, including social cognition. Alterations in mentalizing skills are found in both schizophrenia patients and individuals exposed to childhood trauma. We hypothesize that childhood...

Background The analysis of the information available in many countries on the use of clozapine, systematically indicates low prescription, underdosing and delay in the start of treatment. But as striking as this underutilization is the great variability between territories studied, which are related to multiple factors, and have led to various init...

Background The “dysconnection hypothesis” proposes that schizophrenia is best understood in terms of aberrant brain functional integration and synaptic neuromodulation, which may underlie illness psychopathology and cognitive decline. Impairments in the P300 potential are well documented in schizophrenia and progressive over the years with the illn...

Introduction: International studies on clozapine use usually show lower than expected prescription proportions, under-dosing and delayed initiation of treatment, which has led to a number of initiatives aimed at improving its use and reducing the striking variability observed among practitioners. There are no similar studies on the Spanish populat...

Spectral entropy (SE) allows comparing task-related modulation of electroencephalogram (EEG) between patients and controls, i.e. spectral changes of the EEG associated to task performance. A SE modulation deficit has been replicated in different schizophrenia samples. To investigate the underpinnings of SE modulation deficits in schizophrenia, we a...

Mean cortical curvature may relate to cortico-cortical connections integrity. We explored the association between prefrontal (PFC) cortical curvature and fractional anisotropy (FA) values for tracts connecting PFC and relevant cortical regions. In schizophrenia Anatomical and diffusion magnetic resonance images were obtained from 34 patients (16 of...

The aim of this study was to explore the coupling among neural oscillations in different frequency bands using two approaches: conventional phase-amplitude coupling (PAC) and a novel event-related PAC. Both measures were applied to the electroencephalographic activity from 20 healthy volunteers. The results showed that the phase of alpha band modul...

The aim of this study was to evaluate neural coupling patterns in schizophrenia (SCH) patients and healthy controls during an auditory oddball task. Two measures of functional connectivity were applied to 28 SCH patients and 51 healthy controls to characterize electroencephalographic (EEG) activity. Specifically, magnitude squared coherence (MSC) a...

Spectral entropy (SE) is a measurement from information theory field that provides an estimation of EEG regularity and may be useful as a summary of its spectral properties. Previous studies using small samples reported a deficit of EEG entropy modulation in schizophrenia during cognitive activity. The present study is aimed at replicating this fin...

The aim of this study was to introduce a novel global measure of graph complexity: Shannon graph complexity (SGC). This measure was specifically developed for weighted graphs, but it can also be applied to binary graphs. The proposed complexity measure was designed to capture the interplay between two properties of a system: the 'information' (calc...

Objective. The aim of this paper was to characterize brain non-stationarity during an auditory oddball task in schizophrenia (SCH). The level of non-stationarity was measured in the baseline and response windows of relevant tones in SCH patients and healthy controls. Approach. Event-related potentials were recorded from 28 SCH patients and 51 contr...

Schizophrenia and other psychotic disorders are associated with high morbidity and mortality, due to inherent health factors, genetic factors, and factors related to psychopharmacological treatment. Antipsychotics, like other drugs, have side-effects that can substantially affect the physical health of patients, with substantive differences in the...

Background: Spatial and biological characteristics of structural frontal disconnectivity in schizophrenia remain incompletely understood. Simultaneous streamline count (SC) and fractional anisotropy (FA) analyses may yield relevant complementary information to this end. Methods: Using 3T diffusion magnetic resonance imaging both SC and FA were c...

Objective: Higher mental functions depend on global cerebral functional coordination. Our aim was to study fast modulation of functional networks in schizophrenia that has not been previously assessed. Methods: Graph-theory was used to analyze the electroencephalographic (EEG) activity during an odd-ball task in 57 schizophrenia patients (18 fir...

Functional brain networks possess significant small-world (SW) properties. Genetic variation relevant to both inhibitory and excitatory transmission may contribute to modulate these properties. In healthy controls, genotypic variation in Neuregulin 1 (NRG1) related to the risk of psychosis (risk alleles) would contribute to functional SW modulation...

Abstract Gamma oscillations are key in coordinating brain activity and seem to be altered in schizophrenia. In previous work, we studied the spatial distribution of a noise power measure (scalp-recorded electroencephalographic activity unlocked to stimuli) and found higher magnitudes in the gamma band related to symptoms and cognition in schizophre...

Introduction: Schizophrenia and other psychotic disorders are associated with high morbidity and mortality, due to inherent health factors, genetic factors, and factors related to psychopharmacological treatment. Antipsychotics, like other drugs, have side-effects that can substantially affect the physical health of patients, with substantive diff...

The aim of this study was to characterize brain dynamics during an auditory oddball task. For this purpose, a measure of the non-stationarity of a given time-frequency representation (TFR) was applied to electroencephalographic (EEG) signals. EEG activity was acquired from 20 schizophrenic (SCH) patients and 20 healthy controls while they underwent...

The aim of this study was to assess brain complexity dynamics in schizophrenia (SCH) patients during an auditory oddball task. For this task, we applied a novel graph measure based on the balance of the node weights distribution. Previous studies applied complexity parameters that were strongly dependent on network topology. This could bias the res...

Subclinical psychotic symptoms are associated to negative life outcomes in the general population, but their relationship with cognitive performance is still not well understood. Assessing the relationship between performance in cognitive domains and subclinical psychotic symptoms in the general population may also help understand the handicap attr...

Aim: An association between deficit of electroencephalographic (EEG) modulation during an odd-ball task and psychotic symptoms has been described in clinical samples, in agreement with the proposed role for altered salience in psychosis. To discard the possible influence of medication, the relationship between psychotic-like experiences and EEG mo...

En la población general, los síntomas psicóticos subclínicos se han asociado con mayores dificultades funcionales en la vida real, pero desconocemos si estos síntomas están asociados a un peor rendimiento cognitivo. El estudio de la relación entre las alteraciones cognitivas y estos síntomas puede, además, ayudarnos a comprender mejor las dificulta...

Background: Several biologically distinct subgroups may coexist within schizophrenia, which may hamper the necessary replicability to translate research findings into clinical practice. Methods: Cortical thickness, curvature and area values and subcortical volumes of 203 subjects (121 schizophre-nia patients, out of which 64 were first episodes), 6...

The aim of the present study was to characterize the neural network reorganization during a cognitive task in schizophrenia (SCH) by means of wavelet entropy (WE). Previous studies suggest that the cognitive impairment in patients with SCH could be related to the disrupted integrative functions of neural circuits. Nevertheless, further characteriza...

In schizophrenia, both increased baseline metabolic and electroencephalographic (EEG) activities as well as decreased task-related modulation of neural dynamics have been reported. Noise power (NP) can measure the background EEG activity during task performance, and Shannon entropy (SE) is useful for quantifying the global modulation of EEG activit...

Objective. The aim of this research is to explore the coupling patterns of brain dynamics during an auditory oddball task in schizophrenia (SCH). Approach. Event-related electroencephalographic (ERP) activity was recorded from 20 SCH patients and 20 healthy controls. The coupling changes between auditory response and pre-stimulus baseline were calc...

The analysis of the interaction between novelty and relevance may be of interest to test the aberrant salience hypothesis of schizophrenia (SCH). In comparison with other neuroimaging techniques, such as functional magnetic resonance imaging, electroencephalography (EEG) provides high temporal resolution. Therefore, EEG is useful to analyze transie...

Background Neuregulins are a family of signalling proteins that orchestrate a broad range of cellular responses. Four genes encoding Neuregulins 1–4 have been identified so far in vertebrates. Among them, Neuregulin 1 and Neuregulin 3 have been reported to contribute to an increased risk for developing schizophrenia. We hypothesized that three spec...

Background: Gamma oscillations are essential for functional neural assembly formation underlying higher cerebral functions. Previous studies concerning gamma band power in schizophrenia have yielded diverse results. Methods: In this study, we assessed gamma band power in minimally treated patients with schizophrenia, their first-degree relatives...

Background: The NCAN gene codes for Neurocan, a chondroitin sulfate proteoglycan that is found in the extracellular matrix of the central nervous system. It is interacting with various cell surface structures and proteins of the extracellular matrix, by which it is believed to have an influence on neu-rite outgrowth and neuronal adhesion. In recent...

Spectral entropy (SE), also known as Shannon entropy, is a useful parameter for quantifying the global regularity of the electroencephalographic (EEG) signal. Hence, it is of interest in the assessment of the electrophysiological correlates of cognitive processing in schizophrenia. However, to date, SE has been barely used in studies comparing rest...

This study investigated whether biochemical parameters add predictive information concerning risk for weight gain associated with treatment with atypical antipsychotics (AP) to that provided by baseline weight. Weight changes were assessed in 25 patients with schizophrenia after 3-6 months of treatment. These patients were started on AP monotherapy...

Resumen El diagnóstico de las funciones cognitivas superiores mediante técnicas de cartografía eléctrica cerebral computerizada ha experimentado un enorme auge durante los últimos años debido al abaratamiento de los potentes equipos informáticos empleados en el análisis de la señal electroencefalográfica. Sin embargo, la mayor disponibilidad de est...

The aim of this research was to study the organization of the brain functional network during an auditory oddball task in schizophrenia (SZ). Electroencephalographic (EEG) activity was recorded from 31 schizophrenic patients and 38 healthy controls. In a first step, coherence was used to estimate the similarity between the spectral content of each...

Aims: The aim of this study was to assess the relation between cognition, gray matter (GM) volumes and gamma noise power (amount of background oscilla-tory activity in the gamma band) in schizophrenia. Methods: We explored the relation between cog-nitive performance and regional GM volumes using voxel-based morphometry (VBM), in order to discover i...

The aim of this study was to assess the relation between cognition, gray matter (GM) volumes and gamma noise power (amount of background oscillatory activity in the gamma band) in schizophrenia. We explored the relation between cognitive performance and regional GM volumes using voxel-based morphometry (VBM), in order to discover if the association...

a b s t r a c t The cognitive deficit profile is different among individuals with schizophrenia. We quantified the amount of electroencephalographic activity unlocked to stimuli onset (noise power) over frontal regions regarding deficit in cognitive domains. Forty-six patients with schizophrenia and 27 healthy controls underwent clinical, cognitive...

The current schizophrenia concept is built on experts' agreement on the matter, and it is basically rooted in the epidemiological and clinical evidence. However, the numerous and intensive attempts to find the biological underpinnings of this syndrome face almost constantly a low degree of replication of the results. We have reviewed previously pub...

In first-episode patients with psychosis, clozapine may be potentially valuable as an initial treatment seeking to limit early on clinical and cognitive deterioration. Nevertheless, until recently its restricted use has limited the study of this possibility. Our research group is developing a non-commercial, multicentric and open label study on the...