Nuestros investigadores

Gonzalo Arrondo Ostíz

Mente Cerebro
Instituto Cultura y Sociedad (ICS). Universidad de Navarra
Aprendizaje y Curriculum
Facultad de Educación y Psicología. Universidad de Navarra
Líneas de investigación
Toma de decisiones y función dopaminérgica, Aprendizaje y procesos de recompensa, Epistemología de la psiquiatría, Funciones ejecutivas en trastornos neurodegenerativos, Buenas prácticas en investigación, Meta-análisis y revisiones sistemáticas en psicología
Índice H
16, (Google Scholar, 16/03/2021)
12, (WoS, 16/03/2021)
13, (Scopus, 16/03/2021)

Publicaciones científicas más recientes (desde 2010)

Autores: Musullulu, H.; Bernácer María, Javier; Murillo, J.; et al.
ISSN 0924-9338  Vol. 63  2020  págs. S478 - S478
Autores: Knolle, F.; Garofalo, S. ; Viviani, R.; et al.
ISSN 2213-1582  Vol. 27  2020  págs. 102277
Objective Current research does not provide a clear explanation for why some patients with Parkinson¿s Disease (PD) develop psychotic symptoms. The `aberrant salience hypothesis¿ of psychosis has been influential and proposes that dopaminergic dysregulation leads to inappropriate attribution of salience to irrelevant/non-informative stimuli, facilitating the formation of hallucinations and delusions. The aim of this study is to investigate whether non-motivational salience is altered in PD patients and possibly linked to the development of psychotic symptoms. Methods We investigated salience processing in 14 PD patients with psychotic symptoms, 23 PD patients without psychotic symptoms and 19 healthy controls. All patients were on dopaminergic medication for their PD. We examined emotional salience using a visual oddball fMRI paradigm that has been used to investigate early stages of schizophrenia spectrum psychosis, controlling for resting cerebral blood flow as assessed with arterial spin labelling fMRI. Results We found significant differences between patient groups in brain responses to emotional salience. PD patients with psychotic symptoms had enhanced brain responses in the striatum, dopaminergic midbrain, hippocampus and amygdala compared to patients without psychotic symptoms. PD patients with psychotic symptoms showed significant correlations between the levels of dopaminergic drugs they were taking and BOLD signalling, as well as psychotic symptom scores. Conclusion Our study suggests that enhanced signalling in the striatum, dopaminergic midbrain, the hippocampus and amygdala is associated with the development of psychotic symptoms in PD, in line with that proposed in the `aberrant salience hypothesis¿ of psychosis in schizophrenia.
Autores: Aznárez Sanado, Maite (Autor de correspondencia); Artuch Garde, Raquel; Carrica Ochoa, Sarah; et al.
ISSN 1664-1078  Vol. 11  2020 
Background/objective: Adult Lower Secondary Education is an education program for basic qualifications for the labor market. Our study aimed to compare lifetime mental health problems between current Adult Lower Secondary Education students and higher Vocational Education students, as the former constitutes a highly distinct and understudied group. Methods: Findings were based on a cross-sectional self-report survey. Lifetime relative odds of occurrence of mental disorders [i.e., psychiatric disorders typically diagnosed in adults, learning difficulties or deficit hyperactivity disorder (ADHD)] were compared between Adult Lower Secondary Education students (n = 134) and Vocational Education students (n = 149). Results: While the frequency of mental health problems was high in both groups, psychiatric disorders typically diagnosed in adults were more common in Adult Lower Secondary Education students than among other students. Vocational Education students reported higher rates of ADHD. Conclusion: There is a need for additional psychological resources for Adult Lower Secondary Education students, an educational level that is the last path for many to acquire a basic degree.
Autores: Cortese, S; Solmi, M.; Arrondo Ostíz, Gonzalo; et al.
ISSN 1362-0347  Vol. 23  Nº 4  2020  págs. 135 - 139
Introduction Although several systematic reviews (SRs)/meta-analyses (MAs) on the association between specific mental disorders and specific somatic conditions are available, an overarching evidence synthesis across mental disorders and somatic conditions is currently lacking. We will conduct an umbrella review of SRs/MAs to test: 1) the strength of the association between individual mental disorders and individual somatic conditions in children/adolescents and adults; 2) to which extent associations are specific to individual mental and somatic conditions . Methods and analysis We will search a broad set of electronic databases and contact study authors. We will include SRs with MA or SRs reporting the effect size from individual studies on the association between a number of somatic and mental conditions (as per the International Classification of Diseases, 11th Revision). We will follow an algorithm to select only one SR or MA when more than one are available on the same association. We will rate the quality of included SRs/MAs using the AMSTAR-2 tool. We will assess to which extent mental disorders are selectively associated with specific somatic conditions or if there are transdiagnostic, across-spectra or diagnostic spectrum-specific associations between mental disorders and somatic conditions based on the Transparent, Reporting, Appraising, Numerating, Showing (TRANSD) recommendations. Discussion The present umbrella review will shed light on the association between mental health disorders and somatic conditions, providing useful data for the care of patients with mental health disorders, in particular for early detection and intervention. This work might also add insight to the pathophysiology of mental health conditions, and contribute to the current debate on the value of a transdiagnostic approach in psychiatry.
Autores: Arrondo Ostíz, Gonzalo (Autor de correspondencia)
ISSN 1468-1331  Vol. 27  Nº 2  2020  págs. 213 - 214
Autores: Arrondo Ostíz, Gonzalo (Autor de correspondencia); Murillo Gómez, José Ignacio (Autor de correspondencia); Bernácer María, Javier (Autor de correspondencia)
ISSN 0210-0630  Nº 501  2019  págs. 65 - 70
Revisamos la relación entre una visión integradora del concepto de hábito y el trastorno por déficit de atención e hiperactividad (TDAH), a partir de dificultades propias de esta condición para el estudio, la accidentabilidad, la dieta y el ejercicio, o los procesos adictivos. Proponemos que muchas consecuencias del TDAH pueden entenderse como una dificultad para la creación y el mantenimiento de hábitos positivos.
Autores: Arrondo Ostíz, Gonzalo (Autor de correspondencia); García-Ubasos, L.; Rodríguez-Fernández, M.;
ISSN 2253-9034  Nº 79  2019  págs. 18 - 19
Artículo de divulgación científica sobre el TDAH en adultos
Autores: Ruiz-Goikoetxea, Maite; Cortese, Samuele; Aznárez Sanado, Maite; et al.
ISSN 0149-7634  Vol. 84  2018  págs. 63-71
A systematic review with meta-analyses was performed to: 1) quantify the association between ADHD and risk of unintentional physical injuries in children/adolescents ("risk analysis"); 2) assess the effect of ADHD medications on this risk ("medication analysis"). We searched 114 databases through June 2017. For the risk analysis, studies reporting sex-controlled odds ratios (ORs) or hazard ratios (HRs) estimating the association between ADHD and injuries were combined. Pooled ORs (28 studies, 4,055,620 individuals without and 350,938 with ADHD) and HRs (4 studies, 901,891 individuals without and 20,363 with ADHD) were 1.53 (95% CI=1.40,1.67) and 1.39 (95% CI=1.06,1.83), respectively. For the medication analysis, we meta-analysed studies that avoided the confounding-by-indication bias [four studies with a self-controlled methodology and another comparing risk over time and groups (a "difference in differences" methodology)]. The pooled effect size was 0.879 (95% CI=0.838,0.922) (13,254 individuals with ADHD). ADHD is significantly associated with an increased risk of unintentional injuries and ADHD medications have a protective effect, at least in the short term, as indicated by self-controlled studie
Autores: Ruiz-Goikoetxea, M.; Cortese, S.; Magallón Recalde, Sara; et al.
ISSN 2045-2322  Vol. 8  2018  págs. 7584
Poisoning, a subtype of physical injury, is an important hazard in children and youth. Individuals with ADHD may be at higher risk of poisoning. Here, we conducted a systematic review and meta-analysis to quantify this risk. Furthermore, since physical injuries, likely share causal mechanisms with those of poisoning, we compared the relative risk of poisoning and injuries pooling studies reporting both. As per our pre-registered protocol (PROSPERO ID CRD42017079911), we searched 114 databases through November 2017. From a pool of 826 potentially relevant references, screened independently by two researchers, nine studies (84,756 individuals with and 1,398,946 without the disorder) were retained. We pooled hazard and odds ratios using Robust Variance Estimation, a meta-analytic method aimed to deal with non-independence of outcomes. We found that ADHD is associated with a significantly higher risk of poisoning (Relative Risk = 3.14, 95% Confidence Interval = 2.23 to 4.42). Results also indicated that the relative risk of poisoning is significantly higher than that of physical injuries when comparing individuals with and without ADHD (Beta coefficient = 0.686, 95% Confidence Interval = 0.166 to 1.206). These findings should inform clinical guidelines and public health programs aimed to reduce physical risks in children/adolescents with ADHD.
Autores: Ruiz Goikoetxea, M.; Cortese, S.; Soutullo Esperón, César Alejandro; et al.
ISSN 1695-4033  Vol. 88  Nº 5  2018  págs. 294 - 295
Autores: Ruiz-Goikoetxea, M.; Cortese, S.; Aznárez Sanado, Maite; et al.
Revista: BMJ OPEN
ISSN 2044-6055  Vol. 7  Nº 9  2017  págs. e018027
Attention-deficit hyperactivity disorder (ADHD) has been related to increased rates of unintentional injuries. However, the magnitude of the effect and to which extent variables such as sex, age or comorbidity can influence this relationship is unknown. Additionally, and importantly, it is unclear if, and to which degree, ADHD medications can decrease the number of unintentional injuries. Due to the amount of economic and social resources invested in the treatment of injuries, filling these gaps in the literature is highly relevant from a public health standpoint. Here, we present a protocol for a systematic review and meta-analysis to estimate the relationship between ADHD and unintentional injuries and assess the impact of pharmacological treatment for ADHD METHODS AND ANALYSIS: We will combine results from 114 bibliographic databases for studies relating ADHD and risk of injuries. Bibliographic searches and data extraction will be carried out independently by two researchers. The studies' risk of bias will be assessed using the Newcastle-Ottawa Scale. Articles reporting ORs or HRs of suffering an injury in ADHD compared with controls (or enough data to calculate them) will be combined using Robust Variance Estimation, a method that permits to include multiple non-independent outcomes in the analysis. All analyses will be carried out in Stata. Age, sex and comorbid conduct disorders will be considered as potential causes of variance and their effect analysed through meta-re
Autores: Arrondo Ostíz, Gonzalo; Bernácer María, Javier; Díaz-Robredo, Luis
ISSN 1575-1813  Vol. 18  Nº 4  2017  págs. 267 - 269
La conformación de las estructuras anatómicas es compleja en los 3 planos del espacio. Históricamente, la enseñanza de la anatomía se ha hecho a partir de representaciones bidimensionales, de modelos físicos tridimensionales o de cuerpos reales. Solo recientemente ha sido factible crear modelos anatómicos digitales tridimensionales, que pueden ser explorados en línea a través de Internet. El objetivo del presente trabajo es analizar 2 de las herramientas en línea más conocidas para la visualización anatómica (Anatomography® y BioDigital® Human), y presentar una experiencia docente de uso en el área de neurociencias. Se crearon imágenes de estructuras cerebrales animadas que se usaron en clase posteriormente, y se preguntó a los alumnos sobre su interés y utilidad. Los resultados indicaron que la utilización de este tipo de recursos es interesante por su flexibilidad, atractivo y coste.
Autores: Garofalo, S.; Justicia, A.; Arrondo Ostíz, Gonzalo; et al.
ISSN 1664-2295  Vol. 8  2017  págs. 156
Psychotic symptoms frequently occur in Parkinson's disease (PD), but their pathophysiology is poorly understood. According to the National Institute of Health RDoc programme, the pathophysiological basis of neuropsychiatric symptoms may be better understood in terms of dysfunction of underlying domains of neurocognition in a trans-diagnostic fashion. Abnormal cortico-striatal reward processing has been proposed as a key domain contributing to the pathogenesis of psychotic symptoms in schizophrenia. This theory has received empirical support in the study of schizophrenia spectrum disorders and preclinical models of psychosis, but has not been tested in the psychosis associated with PD. We, therefore, investigated brain responses associated with reward expectation and prediction error signaling during reinforcement learning in PD-associated psychosis. An instrumental learning task with monetary gains and losses was conducted during an fMRI study in PD patients with (n¿=¿12), or without (n¿=¿17), a history of psychotic symptoms, along with a sample of healthy controls (n¿=¿24). We conducted region of interest analyses in the ventral striatum (VS), ventromedial prefrontal and posterior cingulate cortices, and whole-brain analyses. There was reduced activation in PD patients with a history of psychosis, compared to those without, in the posterior cingulate cortex and the VS during reward anticipation (p¿<¿0.05 small volume corrected). The results suggest that cortical and striatal
Autores: Segarra, N.; Metastasio, A.; Ziauddeen, H.; et al.
ISSN 0893-133X  Vol. 41  Nº 8  2016  págs. 2001 - 2010
Alterations in reward processes may underlie motivational and anhedonic symptoms in depression and schizophrenia. However it remains unclear whether these alterations are disorder-specific or shared, and whether they clearly relate to symptom generation or not. We studied brain responses to unexpected rewards during a simulated slot-machine game in 24 patients with depression, 21 patients with schizophrenia, and 21 healthy controls using functional magnetic resonance imaging. We investigated relationships between brain activation, task-related motivation, and questionnaire rated anhedonia. There was reduced activation in the orbitofrontal cortex, ventral striatum, inferior temporal gyrus, and occipital cortex in both depression and schizophrenia in comparison with healthy participants during receipt of unexpected reward. In the medial prefrontal cortex both patient groups showed reduced activation, with activation significantly more abnormal in schizophrenia than depression. Anterior cingulate and medial frontal cortical activation predicted task-related motivation, which in turn predicted anhedonia severity in schizophrenia. Our findings provide evidence for overlapping hypofunction in ventral striatal and orbitofrontal regions in depression and schizophrenia during unexpected reward receipt, and for a relationship between unexpected reward processing in the medial prefrontal cortex and the generation of motivational states.
Autores: Arrondo Ostíz, Gonzalo; Murray, G. K.; Hill, E.; et al.
ISSN 0007-1250  Vol. 207  Nº 1  2015  págs. 79 - 80
Depression and borderline personality disorder (BPD) are both thought to be accompanied by alterations in the subjective experience of environmental rewards. We evaluated responses to sweet, bitter and neutral tastes (juice, quinine and water) in 29 women with depression, 17 women with BPD and 27 female healthy controls (HC). BPD patients gave lower pleasantness and higher disgust ratings for quinine and juice compared to controls; depression patients did not differ significantly from controls. Juice disgust ratings were related to self-disgust in BPD, suggesting close links between abnormal sensory processing and self-identity in BPD.
Autores: Luis García, Elkin Oswaldo; Arrondo Ostíz, Gonzalo; Vidorreta Diaz de Cerio, Marta; et al.
Revista: PLOS ONE
ISSN 1932-6203  Vol. 10  Nº 7  2015  págs. e0131536
BACKGROUND: Imaging studies help to understand the evolution of key cognitive processes related to aging, such as working memory (WM). This study aimed to test three hypotheses in older adults. First, that the brain activation pattern associated to WM processes in elderly during successful low load tasks is located in posterior sensory and associative areas; second, that the prefrontal and parietal cortex and basal ganglia should be more active during high-demand tasks; third, that cerebellar activations are related to high-demand cognitive tasks and have a specific lateralization depending on the condition. METHODS: We used a neuropsychological assessment with functional magnetic resonance imaging and a core N-back paradigm design that was maintained across the combination of four conditions of stimuli and two memory loads in a sample of twenty elderly subjects. RESULTS: During low-loads, activations were located in the visual ventral network. In high loads, there was an involvement of the basal ganglia and cerebellum in addition to the frontal and parietal cortices. Moreover, we detected an executive control role of the cerebellum in a relatively symmetric fronto-parietal network. Nevertheless, this network showed a predominantly left lateralization in parietal regions associated presumably with an overuse of verbal storage strategies. The differential activations between conditions were stimuli-dependent and were located in sensory areas. CONCLUSION: Successful WM processes in the elderly population are accompanied by an activation pattern that involves cerebellar regions working together with a fronto-parietal network.
Autores: Arrondo Ostíz, Gonzalo; Aznárez Sanado, Maite; Fernández Seara, María Asunción; et al.
ISSN 0924-977X  Vol. 25  Nº 6  2015  págs. 817 - 827
Studies on animals and humans have demonstrated the importance of dopamine in modulating decision-making processes. In this work, we have tested dopaminergic modulation of economic decision-making and its neural correlates by administering either placebo or metoclopramide, a dopamine D2-receptor antagonist, to healthy subjects, during a functional MRI study. The decision-making task combined probability and time delay with a fixed monetary reward. For individual behavioral characterization, we used the Probability Time Trade-off (PTT) economic model, which integrates the traditional trade-offs of reward magnitude-time and reward magnitude-probability into a single measurement, thereby quantifying the subjective value of a delayed and probabilistic outcome. A regression analysis between BOLD signal and the PTT model index permitted to identify the neural substrate encoding the subjective reward-value. Behaviorally, medication reduced the rate of temporal discounting over probability, reflected in medicated subjects being more prone to postpone the reward in order to increase the outcome probability. In addition, medicated subjects showed less activity during the task in the postcentral gyrus as well as frontomedian areas, whereas there were no differences in the ventromedial orbitofrontal cortex (VMOFC) between groups when coding the subjective value. The present study demonstrates by means of behavior and imaging that dopamine modulation alters the probability-time trade-off in human economic decision-making.
Autores: Arrondo Ostíz, Gonzalo; Segarra, Nuria; Metastasio, Antonio; et al.
ISSN 1664-1078  Vol. 6  2015  págs. 1280
In the research domain framework (RDoC), dysfunctional reward expectation has been proposed to be a cross-diagnostic domain in psychiatry, which may contribute to symptoms common to various neuropsychiatric conditions, such as anhedonia or apathy/avolition. We used a modified version of the Monetary Incentive Delay (MID) paradigm to obtain functional MRI images from 22 patients with schizophrenia, 24 with depression and 21 controls. Anhedonia and other symptoms of depression, and overall positive and negative symptomatology were also measured. We hypothesized that the two clinical groups would have a reduced activity in the ventral striatum when anticipating reward (compared to anticipation of a neutral outcome) and that striatal activation would correlate with clinical measures of motivational problems and anhedonia. Results were consistent with the first hypothesis: two clusters in both the left and right ventral striatum were found to differ between the groups in reward anticipation. Post-hoc analysis showed that this was due to higher activation in the controls compared to the schizophrenia and the depression groups in the right ventral striatum, with activation differences between depression and controls also seen in the left ventral striatum. No differences were found between the two patient groups, and there were no areas of abnormal cortical activation in either group that survived correction for multiple comparisons. Reduced ventral striatal activity was related to greater anhedonia and overall depressive symptoms in the schizophrenia group, but not in the participants with depression. Findings are discussed in relation to previous literature but overall are supporting evidence of reward system dysfunction across the neuropsychiatric continuum, even if the specific clinical relevance is still not fully understood. We also discuss how the RDoC approach may help to solve some of the replication problems in psychiatric fMRI research.
Autores: Martínez Villar, Martín; Villagra Poviña, Federico; Loayza Paredes, Francis Roderich; et al.
ISSN 0278-0062  Vol. 33  Nº 5  2014  págs. 1044 - 1053
Repetitive and alternating lower limb movements are a specific component of human gait. Due to technical challenges, the neural mechanisms underlying such movements have not been previously studied with functional magnetic resonance imaging. In this study, we present a novel treadmill device employed to investigate the kinematics and the brain activation patterns involved in alternating and repetitive movements of the lower limbs. Once inside the scanner, 19 healthy subjects were guided by two visual cues and instructed to perform a motor task which involved repetitive and alternating movements of both lower limbs while selecting their individual comfortable amplitude on the treadmill. The device facilitated the performance of coordinated stepping while registering the concurrent lower-limb displacements, which allowed us to quantify some movement primary kinematic features such as amplitude and frequency. During stepping, significant blood oxygen level dependent signal increases were observed bilaterally in primary and secondary sensorimotor cortex, the supplementary motor area, premotor cortex, prefrontal cortex, superior and inferior parietal lobules, putamen and cerebellum, regions that are known to be involved in lower limb motor control. Brain activations related to individual adjustments during motor performance were identified in a right lateralized network including striatal, extrastriatal, and fronto-parietal areas.
Autores: Goñi Cortes, Joaquín; Cervantes Ibáñez, Sebastián; Arrondo Ostíz, Gonzalo; et al.
ISSN 1387-2877  Vol. 33  Nº 4  2013  págs. 1009 - 1019
The aim of our study was to elucidate whether specific patterns of gray matter loss were associated with apolipoprotein E epsilon 4 (APOE epsilon 4) and microtubule-associated protein tau (MAPT)-H1) genetic variants in subjects with mild cognitive impairment (MCI) at a baseline visit. Gray matter voxel-based morphometry analysis of T1 magnetic resonance imaging scans were performed in 65 amnestic-MCI subjects. MCI APOE epsilon 4 carriers compared with non-carriers showed increased brain atrophy in right hippocampus and rostral amygdala, superior and middle temporal gyrus, and right parietal operculum, including inferior frontal gyrus, inferior parietal, and supramarginal gyrus. MAPT-H1/H1 MCI carriers showed an increased bilateral atrophy in superior frontal gyri (including frontal eye fields and left prefrontal cortex) and precentral gyrus but also unilateral left atrophy in the inferior temporal gyrus and calcarine gyrus. In addition, MCI subjects carrying both APOE epsilon 4 and MAPT-H1/H1 variants showed gray matter loss in the supplementary motor area and right pre- and postcentral gyri. The effect of APOE epsilon 4 on gray matter loss in right hippocampus suggests that, at least in some AD sub-types, the neuronal vulnerability could be increased in the right hemisphere. The pattern of frontal gray matter loss observed among MCI MAPT H1/H1 carriers has also been found in other tauopathies, suggesting that MCI may share etiological factors with other tauopathies. Frontal and parietal cortex vulnerability was found when adding MAPT H1/H1 and APOE epsilon 4 effects, suggesting a synergistic effect of these variants. These results could be due to changes in APOE epsilon 4 and MAPT expression.
Autores: Goñi Cortes, Joaquín; Sporns, O.; Cheng, H.; et al.
ISSN 1053-8119  Vol. 83  2013  págs. 646 - 657
High-resolution isotropic three-dimensional reconstructions of human brain gray and white matter structures can be characterized to quantify aspects of their shape, volume and topological complexity. In particular, methods based on fractal analysis have been applied in neuroimaging studies to quantify the structural complexity of the brain in both healthy and impaired conditions. The usefulness of such measures for characterizing individual differences in brain structure critically depends on their within-subject reproducibility in order to allow the robust detection of between-subject differences. This study analyzes key analytic parameters of three fractal-based methods that rely on the box-counting algorithm with the aim to maximize within-subject reproducibility of the fractal characterizations of different brain objects, including the pial surface, the cortical ribbon volume, the white matter volume and the gray matter/white matter boundary. Two separate datasets originating from different imaging centers were analyzed, comprising 50 subjects with three and 24 subjects with four successive scanning sessions per subject, respectively. The reproducibility of fractal measures was statistically assessed by computing their intra-class correlations. Results reveal differences between different fractal estimators and allow the identification of several parameters that are critical for high reproducibility. Highest reproducibility with intra-class correlations in the range of 0.9-0.95 is achieved with the correlation dimension. Further analyses of the fractal dimensions of parcellated cortical and subcortical gray matter regions suggest robustly estimated and region-specific patterns of individual variability. These results are valuable for defining appropriate parameter configurations when studying changes in fractal descriptors of human brain structure, for instance in studies of neurological diseases that do not allow repeated measurements or for disease-course longitudinal studies.
Autores: Goñi Cortes, Joaquín; Aznárez Sanado, Maite; Arrondo Ostíz, Gonzalo; et al.
Revista: PLOS ONE
ISSN 1932-6203  Vol. 6   Nº 3  2011  págs. e17408
Decision making can be regarded as the outcome of cognitive processes leading to the selection of a course of action among several alternatives. Borrowing a central measurement from information theory, Shannon entropy, we quantified the uncertainties produced by decisions of participants within an economic decision task under different configurations of reward probability and time. These descriptors were used to obtain blood oxygen level-dependent (BOLD) signal correlates of uncertainty and two clusters codifying the Shannon entropy of task configurations were identified: a large cluster including parts of the right middle cingulate cortex (MCC) and left and right pre-supplementary motor areas (pre-SMA) and a small cluster at the left anterior thalamus. Subsequent functional connectivity analyses using the psycho-physiological interactions model identified areas involved in the functional integration of uncertainty. Results indicate that clusters mostly located at frontal and temporal cortices experienced an increased connectivity with the right MCC and left and right pre-SMA as the uncertainty was higher. Furthermore, pre-SMA was also functionally connected to a rich set of areas, most of them associative areas located at occipital and parietal lobes. This study provides a map of the human brain segregation and integration (i.e., neural substrate and functional connectivity respectively) of the uncertainty associated to an economic decision making paradigm.
Autores: Goñi Cortes, Joaquín; Arrondo Ostíz, Gonzalo; Sepulcre Bernad, Jorge; et al.
Revista: Cognitive Processing - Heidelberg
ISSN 1612-4782  Vol. 12  Nº 2  2011  págs. 183 - 186
Semantic memory is the subsystem of human memory that stores knowledge of concepts or meanings, as opposed to life-specific experiences. How humans organize semantic information remains poorly understood. In an effort to better understand this issue, we conducted a verbal fluency experiment on 200 participants with the aim of inferring and representing the conceptual storage structure of the natural category of animals as a network. This was done by formulating a statistical framework for co-occurring concepts that aims to infer significant concept-concept associations and represent them as a graph. The resulting network was analyzed and enriched by means of a missing links recovery criterion based on modularity. Both network models were compared to a thresholded co-occurrence approach. They were evaluated using a random subset of verbal fluency tests and comparing the network outcomes (linked pairs are clustering transitions and disconnected pairs are switching transitions) to the outcomes of two expert human raters. Results show that the network models proposed in this study overcome a thresholded co-occurrence approach, and their outcomes are in high agreement with human evaluations. Finally, the interplay between conceptual structure and retrieval mechanisms is discussed.
Autores: Arrondo Ostíz, Gonzalo; Sepulcre Bernad, Jorge; Duque, B.; et al.
ISSN 2041-8000  Vol. 2  Nº 1  2010  págs. 11
Background: Language is frequently impaired in multiple sclerosis (MS) in which, in addition to dysarthria and loss of fluency, other language deficits might affect patients and impinge on their quality of life. Aims: The aim of this study was to examine spontaneous language production in MS and to assess its relationship with cognitive deterioration. Methods: Sixteen MS patients and 10 healthy control subjects matched by age and education were studied. Participants were instructed to talk about their life for half an hour. After the transcription of the texts, several parameters were measured, including the number of words, mean and maximum sentence length, lexical density, and number of words produced by the evaluator to maintain conversation. The cognitive impairment of the patients was classified using the Brief Repeatable Battery&#151;Neuropsychology (BRB-N). Results: A decrease in the number of words and in sentence length was detected, as well as an increase in the interventions by the neuropsychologist in patients with MS. Patients with cognitive impairment performed worse in most parameters than control subjects and patients with no cognitive impairment. In addition, the number of words spoken by patients and the interventions by the evaluator were correlated with performance in the Paced Auditory Serial Addition Task and phonetic fluency tests of the BRB-N. Moreover, lexical density was correlated with all cognitive domains. Conclusions: MS patients have structural problems in language production, and flexibility when constructing a complex discourse is also impaired, with both difficulties being related to cognitive impairment, particularly with executive dysfunction. Cognitive impairment is also related to impoverished lexical access.
Autores: Sepulcre Bernad, Jorge; Peraita, Herminia; Goñi Cortes, Joaquín; et al.
ISSN 1380-3395  Vol. 33  Nº 2  2010  págs. 169-175
The aim of the study was to analyze lexical access strategies in patients with multiple sclerosis (MS) and their changes over time. We studied lexical access strategies during semantic and phonemic verbal fluency tests and also confrontation naming in a 2-year prospective cohort of 45 MS patients and 20 healthy controls. At baseline, switching lexical access strategy (both in semantic and in phonemic verbal fluency tests) and confrontation naming were significantly impaired in MS patients compared with controls. After 2 years follow-up, switching score decreased, and cluster size increased over time in semantic verbal fluency tasks, suggesting a failure in the retrieval of lexical information rather than an impairment of the lexical pool. In conclusion, these findings underline the significant presence of lexical access problems in patients with MS and could point out their key role in the alterations of high-level communications abilities in MS.
Autores: Goñi Cortes, Joaquín; Martincorena, I.; Corominas-Murtra, B.; et al.
Revista: International Journal of Bifurcation and Chaos
ISSN 0218-1274  Vol. 20  Nº 3  2010  págs. 913 - 922
Semantic memory is the subsystem of human memory that stores knowledge of concepts or meanings, as opposed to life specific experiences. The organization of concepts within semantic memory can be understood as a semantic network, where the concepts (nodes) are associated (linked) to others depending on perceptions, similarities, etc. Lexical access is the complementary part of this system and allows the retrieval of such organized knowledge. While conceptual information is stored under certain underlying organization (and thus gives rise to a specific topology), it is crucial to have an accurate access to any of the information units, e. g. the concepts, for efficiently retrieving semantic information for real-time need. An example of an information retrieval process occurs in verbal fluency tasks, and it is known to involve two different mechanisms: "clustering", or generating words within a subcategory, and, when a subcategory is exhausted, "switching" to a new subcategory. We extended this approach to random-walking on a network (clustering) in combination to jumping (switching) to any node with certain probability and derived its analytical expression based on Markov chains. Results show that this dual mechanism contributes to optimize the exploration of different network models in terms of the mean first passage time. Additionally, this cognitive inspired dual mechanism opens a new framework to better understand and evaluate exploration, propagation and transport phenomena in other complex systems where switching-like phenomena are feasible.
Autores: Arrondo Ostíz, Gonzalo; Alegre Esteban, Manuel; Villoslada Díaz, Pablo
ISSN 2041-8000  Vol. 1  2010  págs. 1 - 8
Memantine, an uncompetitive, low-affinity N-methyl-D-aspartate (NMDA) receptor antagonist, is an approved compound for use inmoderate to severe Alzheimer¿s disease. Its pharmacological features allow it to block excessive neuronal activation produced by glutamate,while permitting normal activation of the NMDA receptor channel. A review of the trials that have evaluated the use of the compound invascular dementia, Alzheimer¿s disease, or both shows that it is well tolerated and has mild but statistically significant positive effects oncognition and other domains of patients with advanced Alzheimer¿s disease. Recently, a double-blind, placebo-controlled trial in patients withmultiple sclerosis reported neurological worsening in several patients similar to the typical pseudoexacerbations of this disease. Also, the useof memantine in patients with Lewy body disease produces adverse effects. Although the mechanisms of such side-effects are unknown, wesuggest that they could be due to the impairment of synaptic transmission in the demyelinated pathways.
Autores: Arrondo Ostíz, Gonzalo; Murillo Gómez, José Ignacio; Bernácer María, Javier
Libro:  Todo lo que necesitas saber sobre el TDAH en la etapa de aprendizaje
Vol. 501  2019  págs. 65 - 70
Autores: Arrondo Ostíz, Gonzalo; Barrett, Nathaniel; Güell Pelayo, Francisco; et al.
Libro:  Psychiatry and neuroscience update: from translational research to a humanistic approach
Vol. III  2019  págs. 83 - 97
Autores: Güell Pelayo, Francisco; Arrondo Ostíz, Gonzalo; de Castro Manglano, María Pilar; et al.
Libro:  Psychiatry and neuroscience update: A translational approach
Vol. II  2017  págs. 105 - 116
In psychiatry, as in any other medical specialty, the clinician collects information from the patient¿s anamnesis, clinical observation, and diagnostic tests; evaluates these data; and makes a diagnosis. The most common manuals used to assess a patient¿s mental disease according to his or her symptoms are the Diagnostic and Statistical Manual of Mental Disorders (DSM) and the International Classification of Diseases (ICD). This chapter focuses on the dialogue that philosophy and psychiatry have held for decades to achieve a better understanding of dissociative identity disorder (DID). The outcome of this dialogue is the expression of the diagnostic criteria for DID, as well as other dissociative disorders, in the medical manuals. Thus, we first analyze the evolution of DID across the different versions of ICD and DSM. We then show that the characterization of DID and other dissociative disorders is a lively debate that is far from being settled. We demonstrate that the core of this debate is the understanding of person after John Locke¿s philosophy: a person is defined by the apparent expression of consciousness and memories. This leads to what we have termed a primary conceptual dissociation: the mental qualities of the person are dissociated from the body. We propose an alternative account based on the dynamic nature of identity and the understanding of person as a mind¿body unity. We hope that our proposal, which results from the interdisciplinary dialogue between psychiat




En el año 2004 finalicé la licenciatura de psicopedagogía, trabajando posteriormente durante 3 años como educador en un centro para personas con daño cerebral adquirido (Asociación de Daño Cerebral de Navarra). En este tiempo tuve contacto directo con pacientes con sintomatología neurológica muy variada, llevándome a descubrir mi gran interés por las funciones cerebrales superiores en el ser humano. Este interés se formalizó con la consecución de la licenciatura de psicología (UNED) y un máster en neuropsicología clínica (UAB).
En 2007 entré al centro de investigación médica aplicada (CIMA) de la universidad de Navarra como estudiante predoctoral. Durante 1 año trabajé con pacientes con esclerosis múltiple y deterioro cognitivo que participaban en un ensayo clínico, publicando 5 artículos y obteniendo el diploma de estudios avanzados. La participación en dicho ensayo clínico me introdujo en el campo de la epidemiología y el diseño de investigación.
Durante el periodo de tesis doctoral también pude participar en estudios no directamente relacionados con mi trabajo de tesis que han llevado a la publicación de diferentes artículos. Dichos estudios iban desde el análisis de imágenes estructurales cerebrales, al análisis computacional del output léxico en tareas de fluencia verbal o el estudio de los procesos de memoria en personas mayores. Sin embargo, en todos los casos el nexo de unión de los diferentes trabajos era el intento de profundizar en las funciones superiores cognitivas.
Tras la tesis realicé una estancia postdoctoral contratado como investigador por el departamento de psiquiatría de la Universidad de Cambridge de 18 meses durante la cual utilicé las habilidades adquiridas durante la tesis para estudiar los procesos de toma de decisiones en pacientes con depresión y esquizofrenia, publicando 4 artículos.
Tras la estancia, me incorporé al grupo Mente-Cerebro de la UN, donde mis objetivos son profundizar en la comprensión de la toma de decisiones y el hábito en sujetos sanos y con trastornos neuropsiquiátricos. Así mismo estoy interesado en la psicología basada en la evidencia como forma de mejorar la calidad de vida de los pacientes y de las dificultades a la hora de llevarla a la práctica. Estos intereses se han plasmado en sendos capítulos de libro sobre neuropsiquiatría. Como parte de Mente-Cerebro, en 2017 también estoy liderando un proyecto subvencionado por el Gobierno de Navarra para llevar a cabo un metaanálisis sobre el riesgo de lesiones accidentales en este trastorno y el posible efecto protector de la medicación estimulante. El grupo al que he coordinado incluye a S. Cortese, experto mundial en TDAH y evidencia científica y 7 investigadores más. Además del interés clínico y epidemiológico de este proyecto, me ha permitido especializarme en la metodología de la medicina basada en la evidencia, reevaluar la importancia de la transparencia metodológica en investigación, y profundizar en el conocimiento de los trastornos del desarrollo.