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1.
Hum Brain Mapp ; 45(1): e26547, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38060194

RESUMEN

Problem-solving often requires creativity and is critical in everyday life. However, the neurocognitive mechanisms underlying creative problem-solving remain poorly understood. Two mechanisms have been highlighted: the formation of new connections among problem elements and insight solving, characterized by sudden realization of a solution. In this study, we investigated EEG activity during a modified version of the remote associates test, a classical insight problem task that requires finding a word connecting three unrelated words. This allowed us to explore the brain correlates associated with the semantic remoteness of connections (by varying the remoteness of the solution word across trials) and with insight solving (identified as a Eurêka moment reported by the participants). Semantic remoteness was associated with power increase in the alpha band (8-12 Hz) in a left parieto-temporal cluster, the beta band (13-30 Hz) in a right fronto-temporal cluster in the early phase of the task, and the theta band (3-7 Hz) in a bilateral frontal cluster just prior to participants' responses. Insight solving was associated with power increase preceding participants' responses in the alpha and gamma (31-60 Hz) bands in a left temporal cluster and the theta band in a frontal cluster. Source reconstructions revealed the brain regions associated with these clusters. Overall, our findings shed new light on some of the mechanisms involved in creative problem-solving.


Asunto(s)
Encéfalo , Solución de Problemas , Humanos , Solución de Problemas/fisiología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Creatividad , Mapeo Encefálico , Electroencefalografía
2.
Am J Addict ; 33(5): 576-582, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38761123

RESUMEN

BACKGROUND AND OBJECTIVES: Cocaine is a highly addictive substance, and with no approved medication for cocaine use disorder (CUD), leading to a heavy burden. Despite validated psychosocial treatments, relapse rates after detoxification are very high in CUD. Few consistent factors can predict abstinence after detoxification. Our study, therefore, aimed at identifying factors predicting abstinence among CUD patients after inpatient detoxification. METHODS: Eighty-one CUD inpatients were included during detoxification and characterized for clinical and sociodemographic data at baseline and at a follow-up of 3 months after discharge, including a standard measure of their abstinence duration from cocaine. We performed Cox univariate analyzes to determine the factors associated with abstinence maintenance, followed by a multivariate Cox regression to identify independent predictors. RESULTS: Abstinence maintenance was shorter in patients injecting cocaine (hazard ratio [HR] = 5.16, 95% confidence interval [CI]: 2.01-13.27, p < .001) and using cocaine heavily in the month before inclusion (HR = 1.03, 95% CI: 1.00-1.06, p = .046). Conversely, abstinence maintenance was longer in patients with longer inpatient detoxification stays (HR = 0.96, 95% CI: 0.94-0.99, p = .015) and prescribed with selective serotonin reuptake inhibitors (SSRIs) (HR = 0.30, 95% CI: 0.16-0.56, p < .001). DISCUSSION AND CONCLUSIONS: Patients with severe CUD may require longer inpatient stays to achieve abstinence. Regarding SSRI prescription, more specific studies are needed to provide stronger recommendations about their use in clinical practice. SCIENTIFIC SIGNIFICANCE: Our findings suggest several modifiable factors to improve inpatient treatment response in CUD. As there are no specific recommendations about the optimal duration of inpatient stay, our results could pave the way for evidence-based guidelines.


Asunto(s)
Trastornos Relacionados con Cocaína , Humanos , Masculino , Trastornos Relacionados con Cocaína/terapia , Femenino , Adulto , Estudios Prospectivos , Persona de Mediana Edad , Pacientes Internos , Recurrencia , Tiempo de Internación/estadística & datos numéricos
4.
Brain ; 141(1): 217-233, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29182714

RESUMEN

Recent functional imaging findings in humans indicate that creativity relies on spontaneous and controlled processes, possibly supported by the default mode and the fronto-parietal control networks, respectively. Here, we examined the ability to generate and combine remote semantic associations, in relation to creative abilities, in patients with focal frontal lesions. Voxel-based lesion-deficit mapping, disconnection-deficit mapping and network-based lesion-deficit approaches revealed critical prefrontal nodes and connections for distinct mechanisms related to creative cognition. Damage to the right medial prefrontal region, or its potential disrupting effect on the default mode network, affected the ability to generate remote ideas, likely by altering the organization of semantic associations. Damage to the left rostrolateral prefrontal region and its connections, or its potential disrupting effect on the left fronto-parietal control network, spared the ability to generate remote ideas but impaired the ability to appropriately combine remote ideas. Hence, the current findings suggest that damage to specific nodes within the default mode and fronto-parietal control networks led to a critical loss of verbal creative abilities by altering distinct cognitive mechanisms.


Asunto(s)
Asociación , Mapeo Encefálico , Encéfalo/diagnóstico por imagen , Creatividad , Vías Nerviosas/patología , Semántica , Adulto , Anciano , Análisis de Varianza , Señales (Psicología) , Femenino , Hemorragia/diagnóstico por imagen , Hemorragia/patología , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Modelos Neurológicos , Vías Nerviosas/diagnóstico por imagen , Pruebas Neuropsicológicas , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/patología , Adulto Joven
5.
Cereb Cortex ; 27(8): 4033-4047, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27461122

RESUMEN

The nature of the inputs and outputs of a brain region defines its functional specialization. The frontal portion of the brain is essential for goal-directed behaviors, however, the biological basis for its functional organization is unknown. Here, exploring structural connectomic properties, we delineated 12 frontal areas, defined by the pattern of their white matter connections. This result was highly reproducible across neuroimaging centers, acquisition parameters, and participants. These areas corresponded to regions functionally engaged in specific tasks, organized along a rostro-caudal axis from the most complex high-order association areas to the simplest idiotopic areas. The rostro-caudal axis along which the 12 regions were organized also reflected a gradient of cortical thickness, myelination, and cell body density. Importantly, across the identified regions, this gradient of microstructural features was strongly associated with the varying degree of information processing complexity. These new anatomical signatures shed light onto the structural organization of the frontal lobes and could help strengthen the prediction or diagnosis of neurodevelopmental and neurodegenerative disorders.


Asunto(s)
Lóbulo Frontal/diagnóstico por imagen , Lóbulo Frontal/fisiología , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/fisiología , Adulto , Anciano , Conectoma , Femenino , Lóbulo Frontal/anatomía & histología , Lateralidad Funcional , Humanos , Imagenología Tridimensional , Imagen por Resonancia Magnética , Masculino , Metaanálisis como Asunto , Persona de Mediana Edad , Vías Nerviosas/anatomía & histología , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiología , Tamaño de los Órganos , Descanso , Tinción con Nitrato de Plata , Sustancia Blanca/anatomía & histología , Adulto Joven
6.
Brain ; 139(Pt 6): 1783-99, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27076181

RESUMEN

SEE BURGESS DOI101093/BRAIN/AWW092 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE : Analogical reasoning is at the core of the generalization and abstraction processes that enable concept formation and creativity. The impact of neurological diseases on analogical reasoning is poorly known, despite its importance in everyday life and in society. Neuroimaging studies of healthy subjects and the few studies that have been performed on patients have highlighted the importance of the prefrontal cortex in analogical reasoning. However, the critical cerebral bases for analogical reasoning deficits remain elusive. In the current study, we examined analogical reasoning abilities in 27 patients with focal damage in the frontal lobes and performed voxel-based lesion-behaviour mapping and tractography analyses to investigate the structures critical for analogical reasoning. The findings revealed that damage to the left rostrolateral prefrontal region (or some of its long-range connections) specifically impaired the ability to reason by analogies. A short version of the analogy task predicted the existence of a left rostrolateral prefrontal lesion with good accuracy. Experimental manipulations of the analogy tasks suggested that this region plays a role in relational matching or integration. The current lesion approach demonstrated that the left rostrolateral prefrontal region is a critical node in the analogy network. Our results also suggested that analogy tasks should be translated to clinical practice to refine the neuropsychological assessment of patients with frontal lobe lesions.


Asunto(s)
Mapeo Encefálico , Lóbulo Frontal/patología , Corteza Prefrontal/fisiopatología , Pensamiento/fisiología , Adulto , Anciano , Estudios de Casos y Controles , Imagen de Difusión Tensora , Dominancia Cerebral/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Adulto Joven
7.
Cereb Cortex ; 26(3): 915-932, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25331605

RESUMEN

Analogical reasoning is critical for making inferences and adapting to novelty. It can be studied experimentally using tasks that require creating similarities between situations or concepts, i.e., when their constituent elements share a similar organization or structure. Brain correlates of analogical reasoning have mostly been explored using functional imaging that has highlighted the involvement of the left rostrolateral prefrontal cortex (rlPFC) in healthy subjects. However, whether inter-individual variability in analogical reasoning ability in a healthy adult population is related to differences in brain architecture is unknown. We investigated this question by employing linear regression models of performance in analogy tasks and voxel-based morphometry in 54 healthy subjects. Our results revealed that the ability to reason by analogy was associated with structural variability in the left rlPFC and the anterior part of the inferolateral temporal cortex. Tractography of diffusion-weighted images suggested that these 2 regions have a different set of connections but may exchange information via the arcuate fasciculus. These results suggest that enhanced integrative and semantic abilities supported by structural variation in these areas (or their connectivity) may lead to more efficient analogical reasoning.


Asunto(s)
Lóbulo Frontal/anatomía & histología , Lóbulo Temporal/anatomía & histología , Pensamiento , Adulto , Anciano , Envejecimiento , Conectoma , Imagen de Difusión por Resonancia Magnética , Escolaridad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Tiempo de Reacción , Análisis de Regresión , Caracteres Sexuales , Adulto Joven
9.
Hum Brain Mapp ; 37(5): 1953-69, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27012301

RESUMEN

Reasoning by analogy allows us to link distinct domains of knowledge and to transfer solutions from one domain to another. Analogical reasoning has been studied using various tasks that have generally required the consideration of the relationships between objects and their integration to infer an analogy schema. However, these tasks varied in terms of the level and the nature of the relationships to consider (e.g., semantic, visuospatial). The aim of this study was to identify the cerebral network involved in analogical reasoning and its specialization based on the domains of information and task specificity. We conducted a coordinate-based meta-analysis of 27 experiments that used analogical reasoning tasks. The left rostrolateral prefrontal cortex was one of the regions most consistently activated across the studies. A comparison between semantic and visuospatial analogy tasks showed both domain-oriented regions in the inferior and middle frontal gyri and a domain-general region, the left rostrolateral prefrontal cortex, which was specialized for analogy tasks. A comparison of visuospatial analogy to matrix problem tasks revealed that these two relational reasoning tasks engage, at least in part, distinct right and left cerebral networks, particularly separate areas within the left rostrolateral prefrontal cortex. These findings highlight several cognitive and cerebral differences between relational reasoning tasks that can allow us to make predictions about the respective roles of distinct brain regions or networks. These results also provide new, testable anatomical hypotheses about reasoning disorders that are induced by brain damage. Hum Brain Mapp 37:1953-1969, 2016. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Mapeo Encefálico , Encéfalo/fisiología , Formación de Concepto/fisiología , Semántica , Encéfalo/diagnóstico por imagen , Lateralidad Funcional , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Solución de Problemas , Percepción Espacial/fisiología
10.
Brain ; 138(Pt 2): 456-71, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25518957

RESUMEN

Concept formation is the ability to create an abstract link between dissimilar objects or thoughts and is crucial for abstract and creative thinking. This process is related to the integrity of the prefrontal cortex, given the altered performances reported in patients with frontal damage, particularly those suffering from the behavioural variant of frontotemporal dementia. However, the cognitive mechanisms and neural bases of verbal concept formation are not clearly understood. The present study was aimed at addressing the following unresolved issues regarding concept formation in the field of neurology and cognitive neuroscience: (i) Are alterations in concept formation specific to frontotemporal dementia or are they also present in other cortical neurodegenerative disorders such as Alzheimer's disease? (ii) Is impaired performance in concept formation due to cortical lesions specific to frontotemporal dementia or to a cortico-subcortical frontal syndrome? and (iii) What are the cognitive mechanisms and neural bases underlying concept formation? To address these questions, we designed the Verbal Concept Formation Task, an experimental paradigm based on the similarities test. Patients presenting with severe frontal dysfunction (frontotemporal dementia, n = 18, and the Richardson form of progressive supranuclear palsy, n = 21) or with medial temporal pathology (amnestic mild cognitive impairment or Alzheimer's disease, n = 14) and healthy participants (n = 18) were given the Verbal Concept Formation Task and a large battery of neuropsychological tests. In addition, all participants underwent 3D T1-weighted MRI to analyse grey matter volume using voxel-based morphometry. Frontal patients were significantly impaired on the Verbal Concept Formation Task as compared to non-frontal participants (P = 0.00001). Global performance score was positively correlated with scores in cognitive tasks assessing executive functions and with grey matter volume in several areas, mostly in the frontal-basal-ganglion network. Two types of errors were observed in frontal patients. The most frequent was discriminating instead of grouping items ('linking deficit'). Patients also linked items on a concrete instead of an abstract basis ('abstraction deficit'). Linking and abstraction deficits were related to partially different areas: the linking deficit to the dorsal anterior cingulate cortex, right middle frontal gyrus and both inferior parietal lobules and the abstraction deficit to the head of the caudate nuclei and the left superior frontal gyrus. These data suggest that verbal concept formation requires the integrity of the prefrontal-basal-ganglion functional network. In addition, it can be divided into two distinct cognitive processes, which are underlain by two partially different neural networks.


Asunto(s)
Encefalopatías/psicología , Formación de Concepto , Lóbulo Frontal , Demencia Frontotemporal/psicología , Enfermedades Neurodegenerativas/psicología , Adulto , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/psicología , Femenino , Demencia Frontotemporal/patología , Sustancia Gris/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Enfermedades Neurodegenerativas/patología , Pruebas Neuropsicológicas , Estudios Prospectivos , Desempeño Psicomotor
11.
Med Sci (Paris) ; 30(2): 179-85, 2014 Feb.
Artículo en Francés | MEDLINE | ID: mdl-24572117

RESUMEN

Behavioral adaptation to complex or new situations depends on the anatomical, physiological and functional properties of the prefrontal cortex, and on its interaction with other regions. These properties allow distinguishing two main prefrontal regions: the lateral part involved in cognitive aspects of goal-directed behaviors, and the ventral part involved in its affective aspects. Damage to these two regions is associated with two distinct clinical syndromes. Cognitive deficits in planning dominate in the lateral syndrome, behavioral regulation and motivation disorders in the ventral syndrome. Beyond this distinction, the question of how the systems that enable cognitive and behavioral aspects of adaptation are organized in prefrontal subregions, and can be best assessed, is not fully understood. This question is an essential issue in cognitive neuroscience and is crucial to improve clinical practice.


Asunto(s)
Adaptación Psicológica/fisiología , Conducta/fisiología , Corteza Prefrontal/fisiología , Cognición/fisiología , Humanos , Motivación/fisiología
12.
Am Psychol ; 79(3): 403-422, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37578760

RESUMEN

What drives us to search for creative ideas, and why does it feel good to find one? While previous studies demonstrated the positive influence of motivation on creative abilities, how reward and subjective values play a role in creativity remains unknown. This study proposes to characterize the role of individual preferences (how people value ideas) in creative ideation via behavioral experiments and computational modeling. Using the Free Generation of Associates Task coupled with rating tasks, we demonstrate the involvement of valuation processes during idea generation: Preferred ideas are provided faster. We found that valuation depends on the adequacy and originality of ideas and guides response selection and creativity. Finally, our computational model correctly predicts the speed and quality of human creative responses, as well as interindividual differences in creative abilities. Altogether, this model introduces the mechanistic role of valuation in creativity. It paves the way for a neurocomputational account of creativity mechanisms. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Asunto(s)
Creatividad , Motivación , Humanos
13.
Commun Biol ; 7(1): 810, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38961130

RESUMEN

The associative theory of creativity proposes that creative ideas result from connecting remotely related concepts in memory. Previous research found that higher creative individuals exhibit a more flexible organization of semantic memory, generate more uncommon word associations, and judge remote concepts as more related. In this study (N = 93), we used fMRI to investigate brain regions involved in judging the relatedness of concepts that vary in their semantic distance, and how such neural involvement relates to individual differences in creativity. Brain regions where activity increased with semantic relatedness mainly overlapped with default, control, salience, semantic control, and multiple demand networks. The default and semantic control networks exhibited increased involvement when evaluating more remote associations. Finally, higher creative people, who provided higher relatedness judgements on average, exhibited lower activity in those regions, possibly reflecting higher neural efficiency. We discuss these findings in the context of the neurocognitive processing underlying creativity. Overall, our findings indicate that judging remote concepts as related reflects a cognitive mechanism underlying creativity and shed light on the neural correlates of this mechanism.


Asunto(s)
Encéfalo , Creatividad , Imagen por Resonancia Magnética , Semántica , Humanos , Masculino , Femenino , Encéfalo/fisiología , Encéfalo/diagnóstico por imagen , Adulto Joven , Adulto , Mapeo Encefálico/métodos , Memoria/fisiología
14.
Cortex ; 174: 219-233, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38593576

RESUMEN

Assessment of high cognitive functions, such as creativity, is often overlooked in medical practice. However, it is crucial to understand the impact of brain tumors, specifically low-grade gliomas, on creative cognition, as these tumors predominantly affect brain regions associated with cognitive creativity. In this study, we investigated creative cognition using the Alternative Uses Task (AUT) and the Combination of Associates Task (CAT) in a cohort of 29 patients who underwent brain surgery for a low-grade glioma, along with 27 control participants. While the group of patients did not exhibit deficits in clinical neuropsychological assessments, our results revealed significant impairment in generating original and creative ideas compared to the control group. Furthermore, when analyzing the specific brain regions affected by the tumors, patients with lesions overlapping the left rostro-lateral prefrontal cortex, a critical region for creativity, displayed more pronounced impairments in the CAT compared to patients with lesions outside this region. These findings provide proof of concept that patients can experience impaired creative cognition following surgery for low-grade glioma, highlighting the importance of assessing higher-order cognitive functions, including creativity, in neurosurgical patients. Moreover, beyond its clinical relevance, our study contributes to advancing our understanding of the neuroscience of creativity.


Asunto(s)
Glioma , Humanos , Encéfalo , Mapeo Encefálico , Cognición , Creatividad , Glioma/cirugía , Prueba de Estudio Conceptual
15.
Psychiatry Res Neuroimaging ; 342: 111830, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38820804

RESUMEN

AIMS: Cocaine Use Disorder (CUD) is an important health issue, associated with structural brain abnormalities. However, the impact of the route of administration and their predictive value for relapse remain unknown. METHODS: We conducted an anatomical MRI study in 55 CUD patients (26 CUD-Crack and 29 CUD-Hydro) entering inpatient detoxification, and 38 matched healthy controls. In patients, a 3-months outpatient follow-up was carried out to specify the treatment outcome status (relapser when cocaine was consumed once or more during the past month). A Voxel-Based Morphometry approach was used. RESULTS: Compared with controls, CUD patients had widespread gray matter alterations, mostly in frontal and temporal cortices, but also in the cerebellum and several sub-cortical structures. We then compared CUD-Crack with CUD-Hydro patients and found that crack-cocaine use was associated with lower volume in the right inferior and middle temporal gyri, and the right fusiform gyrus. Cerebellar vermis was smaller during detoxification in subsequent relapsers compared to three-months abstainers. CONCLUSIONS: Patients with CUD display widespread cortical and subcortical brain shrinkage. Patients with preferential crack-cocaine use and subsequent relapsers showed specific gray matter volume deficits, suggesting that different patterns of cocaine use and different clinical outcome are associated with different brain macrostructure.


Asunto(s)
Encéfalo , Trastornos Relacionados con Cocaína , Sustancia Gris , Imagen por Resonancia Magnética , Humanos , Trastornos Relacionados con Cocaína/diagnóstico por imagen , Trastornos Relacionados con Cocaína/patología , Masculino , Femenino , Adulto , Resultado del Tratamiento , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Encéfalo/efectos de los fármacos , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Persona de Mediana Edad , Cocaína Crack
16.
Commun Psychol ; 2(1): 54, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-39242875

RESUMEN

Creative problem-solving is central in daily life, yet its underlying mechanisms remain elusive. Restructuring (i.e., reorganization of problem-related representations) is considered one problem-solving mechanism and may lead to an abstract problem-related representation facilitating the solving of analogous problems. Here, we used network science methodology to estimate participants' semantic memory networks (SemNets) before and after attempting to solve a riddle. Restructuring was quantified as the difference in SemNets metrics between pre- and post-solving phases. Our results provide initial evidence that problem-related SemNets restructuring may be associated with the successful solving of the riddle and, subsequently, an analogous one. Solution-relevant concepts and semantically remote concepts became more strongly related in solvers. Only changes in semantically remote concepts were instrumental in actively solving the riddle while changes in solution-relevant concepts may reflect a pre-exposure to the solution.

17.
Cereb Cortex ; 22(10): 2428-40, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22095216

RESUMEN

Some of the most striking symptoms after prefrontal damage are reduction of behavioral initiation and inability to suppress automatic behaviors. However, the relation between these 2 symptoms and the location of the lesions that cause them are not well understood. This study investigates the cerebral correlates of initiation and suppression abilities assessed by the Hayling Sentence Completion Test, using the human lesion approach. Forty-five patients with focal brain lesions and 110 healthy matched controls were examined. We combined a classical group approach with 2 voxel-based lesion methods. The results show several critical prefrontal regions to Hayling Test performance, associated with either common or differential impairment in "initiation" and "suppression" conditions. A crucial role for medial rostral prefrontal cortex (BA 10) in the initiation condition was shown by both group and lesion-mapping methods. A posterior inferolateral lesion provoked both initiation and suppression slowness, although to different degrees. An orbitoventral region was associated with errors in the suppression condition. These findings are important for clinical practice since they indicate that the brain regions required to perform a widely used and sensitive neuropsychological test but also shed light on the regions crucial for distinct components of adaptative behaviors, in particular, rostral prefrontal cortex.


Asunto(s)
Inhibición Psicológica , Intención , Inhibición Neural , Corteza Prefrontal/fisiopatología , Reflejo , Trastornos del Habla/fisiopatología , Habla , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
18.
Hum Brain Mapp ; 33(8): 1973-86, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21769993

RESUMEN

The neural bases of interactions between anxiety and cognitive control are not fully understood. We conducted an fMRI study in healthy participants and in patients with an anxiety disorder (social phobia) to determine the impact of stress on the brain network involved in cognitive control. Participants performed two working memory tasks that differed in their level of performance-induced stress. In both groups, the cognitive tasks activated a frontoparietal network, involved in working memory tasks. A supplementary activation was observed in the right ventrolateral prefrontal cortex (VLPFC) in patients during the more stressful cognitive task. Region of interest analyses showed that activation in the right VLPFC decreased in the more stressful condition as compared to the less stressful one in healthy subjects and remain at a similar level in the two cognitive tasks in patients. This pattern was specific to the right when compared to the left VLPFC activation. Anxiety was positively correlated with right VLPFC activation across groups. Finally, left dorsolateral prefrontal cortex (DLPFC) activation was higher in healthy subjects than in patients in the more stressful task. These findings demonstrate that in healthy subjects, stress induces an increased activation in left DLPFC, a critical region for cognitive control, and a decreased activation in the right VLPFC, an area associated with anxiety. In patients, the differential modulation between these dorsal and ventral PFC regions disappears. This absence of modulation may limit anxious patients' ability to adapt to demanding cognitive control tasks.


Asunto(s)
Mapeo Encefálico/métodos , Memoria a Corto Plazo/fisiología , Trastornos Fóbicos/fisiopatología , Corteza Prefrontal/fisiopatología , Estrés Psicológico/fisiopatología , Adulto , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Masculino
19.
J Int Neuropsychol Soc ; 18(6): 972-85, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23158228

RESUMEN

The aim of this study was to explore the cerebral correlates of functional deficits that occur in behavioral variant frontotemporal dementia (bvFTD). A specific neuropsychological battery, the Social cognition & Emotional Assessment (SEA; Funkiewiez et al., 2012), was used to assess impaired social and emotional functions in 20 bvFTD patients who also underwent structural MRI scanning. The SEA subscores of theory of mind, reversal-learning tests, facial emotion identification, and apathy evaluation were entered as covariates in a voxel-based morphometry analysis. The results revealed that the gray matter volume in the rostral part of the medial prefrontal cortex [mPFC, Brodmann area (BA) 10] was associated with scores on the theory of mind subtest, while gray matter volume within the orbitofrontal (OFC) and ventral mPFC (BA 11 and 47) was related to the scores observed in the reversal-learning subtest. Gray matter volume within BA 9 in the mPFC was correlated with scores on the emotion recognition subtest, and the severity of apathetic symptoms in the Apathy scale covaried with gray matter volume in the lateral PFC (BA 44/45). Among these regions, the mPFC and OFC cortices have been shown to be atrophied in the early stages of bvFTD. In addition, SEA and its abbreviated version (mini-SEA) have been demonstrated to be sensitive to early impairments in bvFTD (Bertoux et al., 2012). Taken together, these results suggest a differential involvement of orbital and medial prefrontal subregions in SEA subscores and support the use of the SEA to evaluate the integrity of these regions in the early stages of bvFTD.


Asunto(s)
Síntomas Afectivos/etiología , Trastornos del Conocimiento/etiología , Lóbulo Frontal/patología , Degeneración Lobar Frontotemporal , Pruebas Neuropsicológicas , Conducta Social , Anciano , Anciano de 80 o más Años , Reacción de Prevención , Femenino , Degeneración Lobar Frontotemporal/complicaciones , Degeneración Lobar Frontotemporal/patología , Degeneración Lobar Frontotemporal/psicología , Humanos , Imagenología Tridimensional , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Reconocimiento en Psicología , Estadística como Asunto , Teoría de la Mente
20.
Cortex ; 151: 281-293, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35462205

RESUMEN

Fatigue is a frequent symptom in many clinical conditions that is still poorly understood despite having a major impact on quality of life. Here, we propose a novel approach using model-based analysis of choice behaviour to extract fatigue markers. We applied this approach to the case of low-grade glioma, with the aim of testing the hypothesis that fatigability in this condition may manifest as limited control over choice impulsivity. Patients with intact or resected glioma (n = 29) and matched healthy controls (n = 27) performed a series of behavioural tasks included in a 4 h-long neuropsychological assessment. Intertemporal choices, opposing smaller-sooner to larger-later monetary rewards, were intermixed with tasks designed to test cognitive and motor performance and to assess perceived fatigue with subjective ratings. All dependent variables were analysed with generalised linear models testing the main effects of group and time-on-task, as well as their interaction. While absent in standard measures of fatigue (subjective rating and objective performance), a significant group-by-time interaction was observed in the rate of impulsive choices: contrary to controls, patients developed a preference for the smaller-sooner option in the course of neuropsychological assessment. This preference shift was captured by computational modelling as an increase in the present bias, a parameter that assigns an additive bonus to immediate rewards. Thus, choice impulsivity was the only reliable marker that reflected the enhanced fatigability of patients relative to controls. These results suggest that the impact of glioma (or its resection) on brain functioning limits the exertion of cognitive control during decision-making. More generally, they pave the way to using model-based analysis of choice behaviour for future investigations of the many clinical conditions plagued with cognitive fatigue.


Asunto(s)
Glioma , Calidad de Vida , Conducta de Elección , Cognición , Glioma/complicaciones , Humanos , Conducta Impulsiva , Recompensa
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