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1.
Psychophysiology ; 61(4): e14491, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38014642

RESUMO

The neurocognitive mechanism underlying negation processing remains controversial. While negation is suggested to modulate the access of word meaning, no such evidence has been observed in the event-related potential (ERP) literature on sentence processing. In the current study, we applied both univariate ERP and multivariate pattern analysis (MVPA) methods to examine the processing of sentence negation. We investigated two types of negative congruent/incongruent sentence pairs with truth-value evaluation (e.g., "A robin is a/not a bird") and without (e.g., "The woman reads a/no book"). In the N400 time window, ERPs consistently showed increased negativity for negative and incongruent conditions. MVPA, on the other hand, revealed nuanced interactions between polarity and congruency. In the later P600 time window, MVPA but not the ERPs revealed an effect of congruency, which may be functionally distinct from the N400 window. We further used cross-decoding to show that the cognitive processes underlying the N400 window for both affirmative and negative sentences are comparable, whereas in the P600 window, only for the truth sentences, negative sentences showed a distinct pattern from their affirmative counterparts. Our results thus speak for a more interactive, but nevertheless serial and biphasic, and potentially construction-specific processing account of negation. We also discuss the advantage of applying MVPA in addition to the classical univariate methods for a better understanding of the neurobiology of negation processing and language comprehension alike.


Assuntos
Eletroencefalografia , Potenciais Evocados , Humanos , Masculino , Feminino , Compreensão , Idioma , Análise Multivariada , Semântica
2.
Eur Arch Psychiatry Clin Neurosci ; 272(3): 395-401, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33961098

RESUMO

Formal thought disorders (FTD) are a hallmark diagnostic feature of schizophrenia (SZ) and (bipolar) mania (MA). FTD can be separated into positive (pFTD) and negative dimensions. It is unclear whether there are differences in pFTD on a single symptom level between acutely ill patients with SZ and MA, which cannot be attributed to cognitive impairment. We compared single pFTD symptoms in two groups of acutely ill patients with ICD-10 bipolar mania and schizophrenia, closely matched for age, sex, pFTD TALD score, verbal IQ and neuropsychological test performance (executive function, verbal fluency, attention, and working memory). SZ patients had higher severity of the TALD symptoms "perseverations" and "poverty of content of speech" than those with MA (Mann-Whitney U, significant, Bonferroni corrected). Speech in acute SZ patients differs from MA in that it conveys little information and adheres to previously mentioned ideas and topics. Matching for confounding variables, such as IQ and cognition, is important when comparing patients with different diagnoses.


Assuntos
Transtornos Cognitivos , Esquizofrenia , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/psicologia , Função Executiva , Humanos , Mania , Testes Neuropsicológicos , Esquizofrenia/complicações , Esquizofrenia/diagnóstico
3.
Behav Res Methods ; 54(1): 365-377, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34240337

RESUMO

Internal states, e.g., emotions, cognitive states, or desires, are often verbalized by figurative means, in particular by embodied metaphors involving human senses, such as touch, taste, and smell. The present paper presents a database for German metaphorical expressions conveying internal states with human senses as their source domains. 168 metaphorical expressions from the source domains of vision, hearing, smell, taste, touch, and temperature combined with literal equivalents were collected and rated by 643 adults. The agreement between the metaphor and an equivalent literal expression, as well as emotional valence, arousal, and familiarity values were assessed using a 7-point Likert scale. Between the metaphorical expressions and their equivalents, familiarity, but not valence or arousal differed significantly while agreement ratings indicated high similarity in meaning. The novel database offers carefully controlled stimuli that can be used in both empirical metaphor research and research on internal state language. Using part of the stimuli in a sentence completion experiment revealed a significant preference for literal over metaphorical expressions that cannot be attributed to higher familiarity levels.


Assuntos
Idioma , Metáfora , Adulto , Compreensão , Emoções , Humanos , Psicolinguística , Reconhecimento Psicológico
4.
Neuroimage ; 237: 118182, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34020020

RESUMO

Gestures are an integral part of in-person conversations and complement the meaning of the speech they accompany. The neural processing of co-speech gestures is supported by a mostly left-lateralized network of fronto-temporal regions. However, in contrast to iconic gestures, metaphoric as well as unrelated gestures have been found to more strongly engage the left and right inferior frontal gyrus (IFG), respectively. With this study, we conducted the first systematic comparison of all three types of gestures and resulting potential laterality effects. During collection of functional imaging data, 74 subjects were presented with 5 s videos of abstract speech with related metaphoric gestures, concrete speech with related iconic gestures and concrete speech with unrelated gestures. They were asked to judge whether the content of the speech and gesture matched or not. Differential contrasts revealed that both abstract related and concrete unrelated compared to concrete related stimuli elicited stronger activation of the bilateral IFG. Analyses of lateralization indices for IFG activation further showed a left hemispheric dominance for metaphoric gestures and a right hemispheric dominance for unrelated gestures. Our results give support to the hypothesis that the bilateral IFG is activated specifically when processing load for speech-gesture combinations is high. In addition, laterality effects indicate a stronger involvement of the right IFG in mismatch detection and conflict processing, whereas the left IFG performs the actual integration of information from speech and gesture.


Assuntos
Lateralidade Funcional/fisiologia , Gestos , Metáfora , Córtex Pré-Frontal/fisiologia , Psicolinguística , Percepção Social , Percepção da Fala/fisiologia , Percepção Visual/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Individualidade , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/diagnóstico por imagem , Adulto Jovem
5.
Hum Brain Mapp ; 41(17): 4901-4911, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32808721

RESUMO

Body orientation of gesture entails social-communicative intention, and may thus influence how gestures are perceived and comprehended together with auditory speech during face-to-face communication. To date, despite the emergence of neuroscientific literature on the role of body orientation on hand action perception, limited studies have directly investigated the role of body orientation in the interaction between gesture and language. To address this research question, we carried out an electroencephalography (EEG) experiment presenting to participants (n = 21) videos of frontal and lateral communicative hand gestures of 5 s (e.g., raising a hand), followed by visually presented sentences that are either congruent or incongruent with the gesture (e.g., "the mountain is high/low…"). Participants underwent a semantic probe task, judging whether a target word is related or unrelated to the gesture-sentence event. EEG results suggest that, during the perception phase of handgestures, while both frontal and lateral gestures elicited a power decrease in both the alpha (8-12 Hz) and the beta (16-24 Hz) bands, lateral versus frontal gestures elicited reduced power decrease in the beta band, source-located to the medial prefrontal cortex. For sentence comprehension, at the critical word whose meaning is congruent/incongruent with the gesture prime, frontal gestures elicited an N400 effect for gesture-sentence incongruency. More importantly, this incongruency effect was significantly reduced for lateral gestures. These findings suggest that body orientation plays an important role in gesture perception, and that its inferred social-communicative intention may influence gesture-language interaction at semantic level.


Assuntos
Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Cinésica , Reconhecimento Visual de Modelos/fisiologia , Córtex Pré-Frontal/fisiologia , Psicolinguística , Leitura , Adulto , Ritmo alfa/fisiologia , Ritmo beta/fisiologia , Feminino , Gestos , Humanos , Masculino , Adulto Jovem
6.
Hum Brain Mapp ; 41(13): 3541-3554, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32432387

RESUMO

The feeling of being addressed is the first step in a complex processing stream enabling successful social communication. Social impairments are a relevant characteristic of patients with major depressive disorder (MDD). Here, we investigated a mechanism which-if impaired-might contribute to withdrawal or isolation in MDD, namely, the neural processing of social cues such as body orientation and gesture. During funtional magnetic resonance imaging (fMRI) data acquisition, 33 patients with MDD and 43 healthy control subjects watched video clips of a speaking actor: one version with a gesture accompanying the speech and one without gesture. Videos were filmed simultaneously from two different viewpoints: one with the actor facing the viewer head-on (frontal) and one side-view (lateral). After every clip, the participants were instructed to evaluate whether they felt addressed or not. Despite overall comparable addressment ratings and a large overlap in activation patterns in MDD and healthy subjects for gesture processing, the anterior cingulate cortex, bilateral superior/middle frontal cortex, and right angular gyrus were more strongly activated in patients than in healthy subjects for the frontal conditions. Our analyses revealed that patients showed specifically higher activation than healthy subjects for the frontal condition without gesture in regions including the posterior cingulate cortex, left prefrontal cortex, and the left hippocampus. We conclude that MDD patients can recognize and interpret social cues such as gesture or body orientation; however, they seem to require more neural resources. This additional effort might affect successful communication and contribute to social isolation in MDD.


Assuntos
Transtorno Depressivo Maior/fisiopatologia , Giro do Cíngulo/fisiopatologia , Hipocampo/fisiopatologia , Cinésica , Córtex Pré-Frontal/fisiopatologia , Interação Social , Percepção Social , Adulto , Mapeamento Encefálico , Sinais (Psicologia) , Transtorno Depressivo Maior/diagnóstico por imagem , Feminino , Gestos , Giro do Cíngulo/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/diagnóstico por imagem , Adulto Jovem
7.
Neuroimage ; 195: 38-47, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-30930310

RESUMO

Gestures are elemental components of social communication and aid comprehension of verbal messages; however, little is known about the potential role of gestures in facilitating processing of semantic complexity in an ecologically valid setting. The goal of this study was to investigate whether cognitive load, as indexed by semantic complexity, is modulated by the presentation of gestures accompanying speech. Twenty healthy participants watched 16 video clips of a short narrative while instructed to carefully listen to and watch the narrator while functional magnetic resonance imaging (fMRI) data were acquired. The videos contained passages with and without various co-speech gestures, as well as passages where the semantic complexity was either low or high, as measured by the metric of idea density. Increasing semantic complexity led to reduced activation within the default mode network (DMN); whereas, presents of gestures decreased activation in language-related regions (left middle temporal gyrus and left inferior frontal gyrus) and increased activation in high-level visual and multimodal regions of occipitotemporal cortex. Most interestingly, an interaction between semantic complexity and gestures was observed in a language-related area in left anterior temporal cortex; specifically, increasing gestures led to a greater drop in activation with high vs. Low semantic complexity. These results provide evidence that the facilitation of gestures on semantic processing, particularly for complex narratives, is reflected in the neural substrates of language processing.


Assuntos
Encéfalo/fisiologia , Compreensão/fisiologia , Gestos , Semântica , Percepção da Fala/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
8.
Hum Brain Mapp ; 39(7): 3072-3085, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29582502

RESUMO

Identifying someone else's noncooperative intentions can prevent exploitation in social interactions. Hence, the inference of another person's mental state might be most pronounced in order to improve social decision-making. Here, we tested the hypothesis that brain regions associated with Theory of Mind (ToM), particularly the right temporo-parietal junction (rTPJ), show higher neural responses when interacting with a selfish person and that the rTPJ-activity as well as cooperative tendencies will change over time. We used functional magnetic resonance imaging (fMRI) and a modified prisoner's dilemma game in which 20 participants interacted with three fictive playing partners who behaved according to stable strategies either competitively, cooperatively or randomly during seven interaction blocks. The rTPJ and the posterior-medial prefrontal cortex showed higher activity during the interaction with a competitive compared with a cooperative playing partner. Only the rTPJ showed a high response during an early interaction phase, which preceded participants increase in defective decisions. Enhanced functional connectivity between the rTPJ and the left hippocampus suggests that social cognition and learning processes co-occur when behavioral adaptation seems beneficial.


Assuntos
Mapeamento Encefálico/métodos , Comportamento Competitivo , Comportamento Cooperativo , Tomada de Decisões/fisiologia , Hipocampo/fisiologia , Lobo Parietal/fisiologia , Córtex Pré-Frontal/fisiologia , Aprendizado Social/fisiologia , Percepção Social , Lobo Temporal/fisiologia , Teoria da Mente/fisiologia , Adulto , Feminino , Hipocampo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Lobo Parietal/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Lobo Temporal/diagnóstico por imagem , Adulto Jovem
9.
Brain Topogr ; 31(5): 838-847, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29500728

RESUMO

Language and action have been thought of as closely related. Comprehending words or phrases that are related to actions commonly activates motor and premotor areas, and this comprehension process interacts with action preparation and/or execution. However, it remains unclear whether comprehending action-related language interacts with action observation. In the current study, we examined whether the observation of tool-use gesture subjects to interaction with language. In an electroencephalography (EEG) study (n = 20), participants were presented with video clips of an actor performing tool-use (TU, e.g., hammering with a fist) and emblematic (EM, e.g., the thumb up sign for 'good job') gestures accompanied by either comprehensible German (G) or incomprehensible Russian sentences (R). Participants performed a semantic judging task, evaluating whether the co-speech gestures were object- or socially-related. Behavioral results from the semantic task showed faster response for the TU versus EM gestures only in the German condition. For EEG, we found that TU elicited beta power decrease (~ 20 Hz) when compared to EM gestures, however this effect was reduced when gestures were accompanied by German instead of Russian sentences. We concluded that the processing of action-related sentences might facilitate gesture observation, in the sense that motor simulation required for TU gestures, as indexed by reduced beta power, was modulated when accompanied by comprehensible German speech. Our results corroborate the functional role of the beta oscillations during perception of hand gestures, and provide novel evidence concerning language-motor interaction.


Assuntos
Ritmo beta/fisiologia , Gestos , Fala/fisiologia , Comportamento de Utilização de Ferramentas/fisiologia , Adulto , Eletroencefalografia , Feminino , Humanos , Julgamento , Masculino , Observação , Estimulação Luminosa , Desempenho Psicomotor/fisiologia , Tempo de Reação , Adulto Jovem
10.
J Neurosci ; 36(48): 12180-12191, 2016 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-27903727

RESUMO

The hierarchical organization of human cortical circuits integrates information across different timescales via temporal receptive windows, which increase in length from lower to higher levels of the cortical hierarchy (Hasson et al., 2015). A recent neurobiological model of higher-order language processing (Bornkessel-Schlesewsky et al., 2015) posits that temporal receptive windows in the dorsal auditory stream provide the basis for a hierarchically organized predictive coding architecture (Friston and Kiebel, 2009). In this stream, a nested set of internal models generates time-based ("when") predictions for upcoming input at different linguistic levels (sounds, words, sentences, discourse). Here, we used naturalistic stories to test the hypothesis that multi-sentence, discourse-level predictions are processed in the dorsal auditory stream, yielding attenuated BOLD responses for highly predicted versus less strongly predicted language input. The results were as hypothesized: discourse-related cues, such as passive voice, which effect a higher predictability of remention for a character at a later point within a story, led to attenuated BOLD responses for auditory input of high versus low predictability within the dorsal auditory stream, specifically in the inferior parietal lobule, middle frontal gyrus, and dorsal parts of the inferior frontal gyrus, among other areas. Additionally, we found effects of content-related ("what") predictions in ventral regions. These findings provide novel evidence that hierarchical predictive coding extends to discourse-level processing in natural language. Importantly, they ground language processing on a hierarchically organized predictive network, as a common underlying neurobiological basis shared with other brain functions. SIGNIFICANCE STATEMENT: Language is the most powerful communicative medium available to humans. Nevertheless, we lack an understanding of the neurobiological basis of language processing in natural contexts: it is not clear how the human brain processes linguistic input within the rich contextual environments of our everyday language experience. This fMRI study provides the first demonstration that, in natural stories, predictions concerning the probability of remention of a protagonist at a later point are processed in the dorsal auditory stream. Results are congruent with a hierarchical predictive coding architecture assuming temporal receptive windows of increasing length from auditory to higher-order cortices. Accordingly, language processing in rich contextual settings can be explained via domain-general, neurobiological mechanisms of information processing in the human brain.


Assuntos
Atenção/fisiologia , Córtex Auditivo/fisiologia , Compreensão/fisiologia , Sinais (Psicologia) , Rede Nervosa/fisiologia , Percepção da Fala/fisiologia , Adulto , Vias Auditivas/fisiologia , Mapeamento Encefálico , Comunicação , Tomada de Decisões/fisiologia , Feminino , Humanos , Masculino , Narração , Reconhecimento Fisiológico de Modelo/fisiologia , Fatores de Tempo
11.
J Cogn Neurosci ; 29(7): 1119-1131, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28294714

RESUMO

While listening to continuous speech, humans process beat information to correctly identify word boundaries. The beats of language are stress patterns that are created by combining lexical (word-specific) stress patterns and the rhythm of a specific language. Sometimes, the lexical stress pattern needs to be altered to obey the rhythm of the language. This study investigated the interplay of lexical stress patterns and rhythmical well-formedness in natural speech with fMRI. Previous electrophysiological studies on cases in which a regular lexical stress pattern may be altered to obtain rhythmical well-formedness showed that even subtle rhythmic deviations are detected by the brain if attention is directed toward prosody. Here, we present a new approach to this phenomenon by having participants listen to contextually rich stories in the absence of a task targeting the manipulation. For the interaction of lexical stress and rhythmical well-formedness, we found one suprathreshold cluster localized between the cerebellum and the brain stem. For the main effect of lexical stress, we found higher BOLD responses to the retained lexical stress pattern in the bilateral SMA, bilateral postcentral gyrus, bilateral middle fontal gyrus, bilateral inferior and right superior parietal lobule, and right precuneus. These results support the view that lexical stress is processed as part of a sensorimotor network of speech comprehension. Moreover, our results connect beat processing in language to domain-independent timing perception.


Assuntos
Encéfalo/fisiologia , Compreensão/fisiologia , Narração , Percepção da Fala/fisiologia , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Oxigênio/sangue , Periodicidade , Fala , Adulto Jovem
12.
Neuroimage ; 136: 10-25, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27177762

RESUMO

Human language allows us to express our thoughts and ideas by combining entities, concepts and actions into multi-event episodes. Yet, the functional neuroanatomy engaged in interpretation of such high-level linguistic input remains poorly understood. Here, we used easy to detect and more subtle "borderline" anomalies to investigate the brain regions and mechanistic principles involved in the use of real-world event knowledge in language comprehension. Overall, the results showed that the processing of sentences in context engages a complex set of bilateral brain regions in the frontal, temporal and inferior parietal lobes. Easy anomalies preferentially engaged lower-order cortical areas adjacent to the primary auditory cortex. In addition, the left supramarginal gyrus and anterior temporal sulcus as well as the right posterior middle temporal gyrus contributed to the processing of easy and borderline anomalies. The observed pattern of results is explained in terms of (i) hierarchical processing along a dorsal-ventral axis and (ii) the assumption of high-order association areas serving as cortical hubs in the convergence of information in a distributed network. Finally, the observed modulation of BOLD signal in prefrontal areas provides support for their role in the implementation of executive control processes.


Assuntos
Córtex Auditivo/fisiologia , Compreensão/fisiologia , Formação de Conceito/fisiologia , Idioma , Semântica , Percepção da Fala/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Masculino , Rede Nervosa/fisiologia
13.
Neuropsychobiology ; 73(3): 139-47, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27058747

RESUMO

The correlation of formal thought disorder (FTD) symptoms and subsyndromes with neuropsychological dimensions is as yet unclear. Evidence for a dysexecutive syndrome and semantic access impairments has been discussed in positive FTD, albeit focusing mostly on patients with schizophrenia. We investigated the correlation of the full range of positive and negative as well as subjective and objective FTD with neuropsychological domains in different patient groups. Patients with ICD-10 schizophrenia (n = 51), depression (n = 51), and bipolar mania (n = 18), as well as healthy subjects (n = 60), were interviewed with the Rating Scale for the Assessment of Objective and Subjective Formal Thought and Language Disorder (TALD) and assessed using a multidimensional neuropsychological test battery (executive function, semantic and lexical verbal fluency, attention, working memory, and abstract thinking). Partial correlation analysis, controlling for age and word knowledge, revealed significant results for the objective positive FTD dimension and executive dysfunctions. Objective negative FTD was associated with deficits in lexico-semantic retrieval, as well as attention and working memory dysfunctions. The results suggest that different neuropsychological substrates correlate with the multidimensional and phenomenologically different FTD syndromes. FTD is a complex, multidimensional syndrome with a variety of neuropsychological impairments, which should be accounted for in future studies investigating the pathogenesis of FTD.


Assuntos
Transtornos Psicóticos Afetivos/psicologia , Transtorno Bipolar/psicologia , Transtorno Depressivo/psicologia , Transtornos da Linguagem/psicologia , Esquizofrenia , Psicologia do Esquizofrênico , Distúrbios da Fala/psicologia , Adolescente , Adulto , Idoso , Atenção , Função Executiva , Feminino , Humanos , Masculino , Memória de Curto Prazo , Pessoa de Meia-Idade , Testes Neuropsicológicos , Transtornos Psicóticos/psicologia , Semântica , Pensamento , Adulto Jovem
14.
Hum Brain Mapp ; 36(5): 1925-36, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25640962

RESUMO

During face-to-face communication, body orientation and coverbal gestures influence how information is conveyed. The neural pathways underpinning the comprehension of such nonverbal social cues in everyday interaction are to some part still unknown. During fMRI data acquisition, 37 participants were presented with video clips showing an actor speaking short sentences. The actor produced speech-associated iconic gestures (IC) or no gestures (NG) while he was visible either from an egocentric (ego) or from an allocentric (allo) position. Participants were asked to indicate via button press whether they felt addressed or not. We found a significant interaction of body orientation and gesture in addressment evaluations, indicating that participants evaluated IC-ego conditions as most addressing. The anterior cingulate cortex (ACC) and left fusiform gyrus were stronger activated for egocentric versus allocentric actor position in gesture context. Activation increase in the ACC for IC-ego>IC-allo further correlated positively with increased addressment ratings in the egocentric gesture condition. Gesture-related activation increase in the supplementary motor area, left inferior frontal gyrus and right insula correlated positively with gesture-related increase of addressment evaluations in the egocentric context. Results indicate that gesture use and body-orientation contribute to the feeling of being addressed and together influence neural processing in brain regions involved in motor simulation, empathy and mentalizing.


Assuntos
Encéfalo/fisiologia , Gestos , Percepção de Movimento/fisiologia , Orientação , Percepção Social , Fala , Adulto , Mapeamento Encefálico , Comunicação , Compreensão/fisiologia , Feminino , Humanos , Relações Interpessoais , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/fisiologia , Testes Neuropsicológicos , Tempo de Reação , Autoimagem , Gravação em Vídeo , Adulto Jovem
15.
Hum Brain Mapp ; 36(11): 4231-46, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26356583

RESUMO

The neural correlates of theory of mind (ToM) are typically studied using paradigms which require participants to draw explicit, task-related inferences (e.g., in the false belief task). In a natural setup, such as listening to stories, false belief mentalizing occurs incidentally as part of narrative processing. In our experiment, participants listened to auditorily presented stories with false belief passages (implicit false belief processing) and immediately after each story answered comprehension questions (explicit false belief processing), while neural responses were measured with functional magnetic resonance imaging (fMRI). All stories included (among other situations) one false belief condition and one closely matched control condition. For the implicit ToM processing, we modeled the hemodynamic response during the false belief passages in the story and compared it to the hemodynamic response during the closely matched control passages. For implicit mentalizing, we found activation in typical ToM processing regions, that is the angular gyrus (AG), superior medial frontal gyrus (SmFG), precuneus (PCUN), middle temporal gyrus (MTG) as well as in the inferior frontal gyrus (IFG) billaterally. For explicit ToM, we only found AG activation. The conjunction analysis highlighted the left AG and MTG as well as the bilateral IFG as overlapping ToM processing regions for both implicit and explicit modes. Implicit ToM processing during listening to false belief passages, recruits the left SmFG and billateral PCUN in addition to the "mentalizing network" known form explicit processing tasks.


Assuntos
Mapeamento Encefálico/métodos , Córtex Cerebral/fisiologia , Compreensão/fisiologia , Teoria da Mente/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
16.
Hum Brain Mapp ; 36(1): 378-90, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25220293

RESUMO

The A allele of the single nucleotide polymorphism (SNP) rs1064395 in the NCAN gene has recently been identified as a susceptibility factor for bipolar disorder and schizophrenia. NCAN encodes neurocan, a brain-specific chondroitin sulfate proteoglycan that is thought to influence neuronal adhesion and migration. Several lines of research suggest an impact of NCAN on neurocognitive functioning. In the present study, we investigated the effects of rs1064395 genotype on neural processing and cognitive performance in healthy subjects. Brain activity was measured with functional magnetic resonance imaging (fMRI) during an overt semantic verbal fluency task in 110 healthy subjects who were genotyped for the NCAN SNP rs1064395. Participants additionally underwent comprehensive neuropsychological testing. Whole brain analyses revealed that NCAN risk status, defined as AA or AG genotype, was associated with a lack of task-related deactivation in a large left lateral temporal cluster extending from the middle temporal gyrus to the temporal pole. Regarding neuropsychological measures, risk allele carriers demonstrated poorer immediate and delayed verbal memory performance when compared to subjects with GG genotype. Better verbal memory performance was significantly associated with greater deactivation of the left temporal cluster during the fMRI task in subjects with GG genotype. The current data demonstrate that common genetic variation in NCAN influences both neural processing and cognitive performance in healthy subjects. Our study provides new evidence for a specific genetic influence on human brain function.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Proteoglicanas de Sulfatos de Condroitina/genética , Cognição/fisiologia , Lectinas Tipo C/genética , Proteínas do Tecido Nervoso/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Encéfalo/irrigação sanguínea , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Voluntários Saudáveis , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Neurocam , Testes Neuropsicológicos , Oxigênio/sangue , Esquizofrenia , Aprendizagem Verbal , Adulto Jovem
17.
Eur Arch Psychiatry Clin Neurosci ; 264(7): 631-45, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24557502

RESUMO

Major depression is associated with impairments in semantic verbal fluency (VF). However, the neural correlates underlying dysfunctional cognitive processing in depressed subjects during the production of semantic category members still remain unclear. In the current study, an overt and continuous semantic VF paradigm was used to examine these mechanisms in a representative sample of 33 patients diagnosed with a current episode of unipolar depression and 33 statistically matched healthy controls. Subjects articulated words in response to semantic category cues while brain activity was measured with functional magnetic resonance imaging (fMRI). Compared to controls, patients showed poorer task performance. On the neural level, a group by condition interaction analysis, corrected for task performance, revealed a reduced task-related deactivation in patients in the right parahippocampal gyrus, the right fusiform gyrus, and the right supplementary motor area. An additional and an increased task-related activation in patients were observed in the right precentral gyrus and the left cerebellum, respectively. These results indicate that a failure to suppress potentially interfering activity from inferior temporal regions involved in default-mode network functions and visual imagery, accompanied by an enhanced recruitment of areas implicated in speech initiation and higher-order language processes, may underlie dysfunctional cognitive processing during semantic VF in depression. The finding that patients with depression demonstrated both decreased performance and aberrant brain activation during the current semantic VF task demonstrates that this paradigm is a sensitive tool for assessing brain dysfunctions in clinical populations.


Assuntos
Mapeamento Encefálico , Encéfalo/patologia , Transtorno Depressivo Maior/complicações , Transtornos da Linguagem/etiologia , Transtornos da Linguagem/patologia , Semântica , Adulto , Encéfalo/irrigação sanguínea , Estudos de Casos e Controles , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Comportamento Verbal , Adulto Jovem
18.
Front Psychiatry ; 15: 1402818, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38938468

RESUMO

Background: In schizophrenia patients, spontaneous speech production has been hypothesized as correlating with right hemispheric activation, including the inferior frontal and superior temporal gyri as speech-relevant areas. However, robust evidence for this association is still missing. The aim of the present fMRI study is to examine BOLD signal changes during natural, fluent speech production in patients with schizophrenia in the chronic phase of their disease. Methods: Using a case-control design, the study included 15 right-handed patients with schizophrenia spectrum disorders as well as 15 healthy controls. The participants described eight pictures from the Thematic Apperception Test for 1 min each, while BOLD signal changes were measured with 3T fMRI. The occurrence of positive and negative formal thought disorders was determined using standardized psychopathological assessments. Results: We found significant BOLD signal changes during spontaneous speech production in schizophrenia patients compared to healthy controls, particularly in the right hemispheric network. A post-hoc analysis showed that this right-hemispheric lateralization was mainly driven by activation during experimental rests. Furthermore, the TLI sum value in patients correlated negatively with BOLD signal changes in the right Rolandic operculum. Conclusions: Possible underlying factors for this inverse right-hemispheric lateralization of speech-associated areas are structural changes and transmitter system alterations, as well as a lack of neural downregulation in schizophrenia patients during rest periods due to dysfunctional executive functions. When examining spontaneous speech as the most natural form of language, other influencing factors, such as social cognition or emotional processing, should be considered. Our results indicate that future studies should consider group differences during rest, which might provide additional information typically covered in differential contrasts.

19.
Int J Neuropsychopharmacol ; 16(4): 745-54, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22906553

RESUMO

Previous positron emission tomography (PET) studies employing competition paradigms have shown either no change or substantial declines in striatal [(11)C]-raclopride binding after challenge with psychotogenic doses of the N-methyl-D-aspartate antagonist ketamine. We sought to probe the relationship between the severity of ketamine-induced psychotic symptoms and altered dopamine D(2/3) receptor availability throughout brain using the high affinity ligand [(18)F]-fallypride (FP). PET recordings were obtained in a group of 10 healthy, young male volunteers, in a placebo condition, and in the course of an infusion with ketamine at a psychotomimetic dose. Administration of the Positive and Negative Syndrome Scale and the Thought and Language Index in both conditions revealed a substantial emergence of mainly negative symptoms of schizophrenia, persisting until the end of the 3 h PET recordings. The baseline FP binding in cortex, caudate nucleus and other brain regions was highly predictive of the individual severity of psychotic symptoms in the ketamine condition. However, there was no evidence of ketamine-evoked reductions in FP binding. In the context of earlier findings, we speculate that high baseline D(2/3)-receptor availability may impart benefits with regard to cognitive flexibility, but increases the risk of maladaptive information processing in the face of environmental stresses and challenges.


Assuntos
Benzamidas/metabolismo , Genética Comportamental/efeitos dos fármacos , Ketamina/metabolismo , Receptores de Dopamina D2/biossíntese , Receptores de Dopamina D3/biossíntese , Adulto , Humanos , Ketamina/farmacologia , Masculino , Tomografia por Emissão de Pósitrons/métodos , Ligação Proteica/fisiologia , Método Simples-Cego , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia , Adulto Jovem
20.
Psychopathology ; 46(6): 390-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23407056

RESUMO

The Scale for the Assessment of Thought, Language and Communication (TLC) represents an instrument for the assessment of formal thought disorder (FTD). The factorial dimensionality of the TLC has yielded ambiguous results for a distinction between positive (e.g. circumstantiality) and negative (e.g. poverty of speech) FTD. The purpose of the current study was to first translate and validate the TLC scale in German. Second, the internal structure was explored in order to identify different FTD dimensions. Two hundred and ten participants (146 patients with ICD-10 diagnoses: depression n = 63, schizophrenia n = 63, mania n = 20; 64 healthy subjects) were interviewed and FTD was rated with the TLC. The principal component analysis of the German TLC version revealed a 3-factor solution, reflecting a disorganized factor, an emptiness factor and a linguistic control factor. The current investigation yielded similar results to those originally reported for the TLC. Thus, a distinction between a positive disorganized, a negative and a semantic word level factor can be supported for the German translation.


Assuntos
Transtorno Bipolar/psicologia , Comunicação , Depressão/psicologia , Escalas de Graduação Psiquiátrica/normas , Psicologia do Esquizofrênico , Semântica , Adulto , Transtorno Bipolar/diagnóstico , Depressão/diagnóstico , Análise Fatorial , Feminino , Alemanha , Humanos , Classificação Internacional de Doenças , Entrevista Psicológica , Idioma , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Esquizofrenia/diagnóstico , Traduções
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