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1.
Artigo em Inglês | MEDLINE | ID: mdl-34064987

RESUMO

Cancer is a very distressing disease, not only for the patients themselves, but also for their family members and relatives. Therefore, patients are regularly monitored to decide whether psychological treatment is necessary and applicable. However, such monitoring processes are costly in terms of required staff and time. Mobile data collection is an emerging trend in various domains. The medical and psychological field benefits from such an approach, which enables experts to quickly collect a large amount of individual health data. Mobile data collection applications enable a more holistic view of patients and assist psychologists in taking proper actions. We developed a mobile application, FeelBack, which is designed to support data collection that is based on well-known and approved psychological instruments. A controlled pilot evaluation with 60 participants provides insights into the feasibility of the developed platform and it shows the initial results. 31 of these participants received paper-based questionnaire and 29 followed the digital approach. The results reveal an increase of the overall acceptance by 58.5% in the mean when using a digital screening as compared to the paper-based. We believe that such a platform may significantly improve cancer patients' and relatives' psychological treatment, as available data can be used to optimize treatment.


Assuntos
Aplicativos Móveis , Psico-Oncologia , Humanos , Corpo Clínico , Monitorização Fisiológica , Inquéritos e Questionários
2.
BMJ Open ; 10(10): e035599, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020078

RESUMO

INTRODUCTION: Cancer burdens not only the patient but also the partner to a comparable extent. Partners of patients with cancer are highly involved in the caring process and therefore often experience distress and report a low quality of life. Interventions for supporting partners are scarce. Existing ones are rarely used by partners because they are often time-consuming per se and offer only limited flexibility with regard to schedule and location. The online intervention PartnerCARE has been developed on the basis of caregiver needs and consists of six consecutive sessions and four optional sessions, which are all guided by an e-coach. The study aims to evaluate feasibility and acceptance of the online intervention PartnerCARE and the related trial process. In addition, first insights of the putative efficacy of PartnerCARE should be gained. METHODS AND ANALYSIS: A two-arm parallel-group randomised controlled trial will be conducted to compare the PartnerCARE online intervention with a waitlist control group. The study aims to recruit in total n=60 partners of patients with any type of cancer across different access paths (eg, university medical centres, support groups, social media). Congruent with feasibility study objectives, the primary outcome comprises recruitment process, study procedure, acceptance and satisfaction with the intervention (Client Satisfaction Questionnaire adapted to Internet-based interventions), possible negative effects (Inventory of Negative Effects in Psychotherapy) and dropout rates. Secondary outcomes include quality of life, distress, depression, anxiety, caregiver burden, fear of progression, social support, self-efficacy, coping and loneliness. Online measurements will be performed by self-assessment at three time points (baseline/pre-randomisation, 2 months and 4 months after randomisation). Data analyses will be based on intention-to-treat principle. ETHICS AND DISSEMINATION: Ethics approval has been granted by the Ethics Committee of the University of Ulm (No 390/18). Results from this study will be disseminated to relevant healthcare communities, in peer-reviewed journals and at scientific and clinical conferences. TRIAL REGISTRATION NUMBER: DRKS00017019.


Assuntos
Intervenção Baseada em Internet , Neoplasias , Estudos de Viabilidade , Humanos , Neoplasias/terapia , Psico-Oncologia , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
BMC Cancer ; 19(1): 885, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488083

RESUMO

BACKGROUND: Suffering from cancer confronts both the patient and their partner with a number of psychosocial challenges in various aspects of their life. These challenges may differentially impact on quality of life, coping ability and compliance to treatment. This especially holds true for haemato-oncological diseases. To date, psychological interventions have predominantly been developed for oncological patients however specific interventions for partners of haemato-oncological patients are rare. In this study we aim to conduct a psycho-oncological group-intervention for partners of patients with haemato-oncological diseases. The aim of the intervention is to significantly reduce symptoms of depression and anxiety in the partners and the patient, as well as enhancing dyadic coping. METHODS: The design of the INPART-study is an unblinded, randomised controlled trial with 2 treatment conditions (experimental and control) and assessments at baseline, 3 and 6 months. It will be conducted at three study centres: the university medical centre's in Leipzig, Hannover and Ulm. The outcome criteria will be a reduction in depressive and anxiety symptoms as well as an improvement of dyadic coping. DISCUSSION: This trial shall provide information regarding the efficiency of a psycho-oncological intervention for partners of patients with haemato-oncological diseases and give references to the possible outcome in terms of dyadic coping and the reduction of mental strain. The study was supported by a grant from the German José Carreras Leukaemia Foundation. TRIAL REGISTRATION: ISRCTN16085028 ; 20/03/2019.


Assuntos
Intervenção Médica Precoce/métodos , Neoplasias Hematológicas/psicologia , Parceiros Sexuais/psicologia , Cônjuges/psicologia , Adaptação Psicológica , Análise de Variância , Ansiedade/prevenção & controle , Depressão/prevenção & controle , Estudos de Viabilidade , Feminino , Seguimentos , Alemanha , Humanos , Masculino , Qualidade de Vida/psicologia , Tamanho da Amostra , Estresse Psicológico/psicologia , Inquéritos e Questionários
4.
Breast Care (Basel) ; 13(2): 102-108, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29887786

RESUMO

This review focuses on the question whether mindfulness in follow-up care can contribute to the prevention of breast cancer (BC) recurrence. We first introduce behavioral risk and protective factors in follow-up care by presenting current research outcomes modulating individual risk for recurrence. We argue that although increased self-awareness is undoubtedly beneficial for BC survivors, it may also trigger adverse effects in vulnerable individuals such as overarousal and impaired emotional regulation. Indeed, research shows that many BC survivors are often confronted with clinical levels of fear of recurrence and anxiety and depressive symptoms. Research on awareness about the impact of behavior on health and fear of recurrence also offers interesting insights which can help to better understand non-compliant responses of BC survivors to medical recommendations regarding lifestyle or screening in follow-up care. Given the high rate of clinically relevant symptoms such as fear of recurrence and anxiety that may be related to dysfunctional levels of self-monitoring, we review the effects of a therapeutic intervention called Mindfulness-Based Stress Reduction (MBSR) that appears promising in reintegrating self-observation with patient well-being.

5.
Front Psychol ; 9: 270, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29559941

RESUMO

Deficits in inhibitory function are assumed to underlie psychopathology in bipolar disorder (BD), especially in states of mania. A subdomain of inhibition, semantic inhibition (SI), referring to the suppression of irrelevant word meanings, may underlie formal thought disorder, such as flights of ideas. In the present study, we investigated SI in patients with BD during semantic ambiguity resolution using behavioral and event-related potential (ERP) measures. We presented 14 patients with BD with current manic, hypomanic, or mixed clinical states and 28 healthy controls sequentially with word triplets containing either a homonym (e.g., "organ") or a comparable unambiguous word (e.g., "piano"). Participants were instructed to make a decision whether or not the target word was related to the meaning field of the first two words. The inappropriate homonym meaning had to be inhibited to correctly perform the target decision. In addition to reaction times (RT) and error rates (ER), the N400 ERP component to the target, an electrophysiological index of semantic processing, was analyzed as measure of the amount of SI that had taken place. Analyses of the behavioral data revealed that BD patients exhibited an overall worse performance in terms of RT and ER. In the ERP data, we found differences in N400 amplitude to ambiguous and unambiguous conditions over the right hemisphere in patients with BD depending on target congruence: In incongruent trials, N400 amplitude was smaller in ambiguous than in unambiguous words. In congruent trials, in contrast, N400 amplitude was larger in ambiguous than in unambiguous words. Such ERP differences between ambiguous and unambiguous words were absent in controls. We conclude that N400 amplitude differences in the ambiguous and unambiguous conditions of the BD group may reflect insufficient suppression of irrelevant homonym meanings in the right hemisphere. Disturbed SI processes might contribute to formal thought disorder in BD.

6.
PLoS One ; 10(4): e0123686, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25923740

RESUMO

Using functional magnetic resonance imaging during a primed visual lexical decision task, we investigated the neural and functional mechanisms underlying modulations of semantic word processing through hypnotic suggestions aimed at altering lexical processing of primes. The priming task was to discriminate between target words and pseudowords presented 200 ms after the prime word which was semantically related or unrelated to the target. In a counterbalanced study design, each participant performed the task once at normal wakefulness and once after the administration of hypnotic suggestions to perceive the prime as a meaningless symbol of a foreign language. Neural correlates of priming were defined as significantly lower activations upon semantically related compared to unrelated trials. We found significant suggestive treatment-induced reductions in neural priming, albeit irrespective of the degree of suggestibility. Neural priming was attenuated upon suggestive treatment compared with normal wakefulness in brain regions supporting automatic (fusiform gyrus) and controlled semantic processing (superior and middle temporal gyri, pre- and postcentral gyri, and supplementary motor area). Hence, suggestions reduced semantic word processing by conjointly dampening both automatic and strategic semantic processes.


Assuntos
Imageamento por Ressonância Magnética , Semântica , Adulto , Análise de Variância , Comportamento , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Humanos , Idioma , Radiografia , Tempo de Reação , Sugestão , Adulto Jovem
7.
Neuroimage ; 86: 194-202, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23959200

RESUMO

Flow refers to a positive, activity-associated, subjective experience under conditions of a perceived fit between skills and task demands. Using functional magnetic resonance perfusion imaging, we investigated the neural correlates of flow in a sample of 27 human subjects. Experimentally, in the flow condition participants worked on mental arithmetic tasks at challenging task difficulty which was automatically and continuously adjusted to individuals' skill level. Experimental settings of "boredom" and "overload" served as comparison conditions. The experience of flow was associated with relative increases in neural activity in the left anterior inferior frontal gyrus (IFG) and the left putamen. Relative decreases in neural activity were observed in the medial prefrontal cortex (MPFC) and the amygdala (AMY). Subjective ratings of the flow experience were significantly associated with changes in neural activity in the IFG, AMY, and, with trend towards significance, in the MPFC. We conclude that neural activity changes in these brain regions reflect psychological processes that map on the characteristic features of flow: coding of increased outcome probability (putamen), deeper sense of cognitive control (IFG), decreased self-referential processing (MPFC), and decreased negative arousal (AMY).


Assuntos
Nível de Alerta/fisiologia , Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Cognição/fisiologia , Motivação/fisiologia , Resolução de Problemas/fisiologia , Análise e Desempenho de Tarefas , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Matemática , Adulto Jovem
8.
J Cogn Neurosci ; 25(12): 2216-29, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23859642

RESUMO

Using fMRI during a lexical decision task, we investigated the neural correlates of semantic priming under masked and unmasked prime presentation conditions in a repeated measurement design of the same group of 24 participants (14 women). The task was to discriminate between pseudowords and words. Masked and unmasked prime words differed in their degree of semantic relatedness with target stimuli. Neural correlates of priming were defined as significantly different neural activations upon semantically unrelated minus related trials. Left fusiform gyrus, left posterior inferior frontal gyrus, and bilateral pre-SMA showed priming effects independent of the masking condition. By contrast, bilateral superior temporal gyri, superior parietal lobules, and the SMA proper demonstrated greater neural priming in the unmasked compared with the masked condition. The inverted contrast (masked priming minus unmasked priming) did not show significant differences even at lowered thresholds of significance. The conjoint effects of priming in the left fusiform gyrus suggest its involvement as a direct consequence of the neural organization of semantic memory. Activity in brain regions showing significantly more neural priming in the unmasked condition possibly reflected participants' evaluation of the prime-target relationship, presumably in the context of semantic matching. The present results therefore indicate that masked and unmasked semantic priming partially depend on dissociable mechanisms at the neural and most likely also at the functional level.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/metabolismo , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Semântica , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Adulto Jovem
9.
Cortex ; 49(2): 474-86, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22405961

RESUMO

Conceptual knowledge is classically supposed to be abstract and represented in an amodal unitary system, distinct from the sensory and motor brain systems. A more recent embodiment view of conceptual knowledge, however, proposes that concepts are grounded in distributed modality-specific brain areas which typically process sensory or action-related object information. Recent neuroimaging evidence suggested the significance of left auditory association cortex encompassing posterior superior and middle temporal gyrus in coding conceptual sound features of everyday objects. However, a causal role of this region in processing conceptual sound information has yet to be established. Here we had the unique chance to investigate a patient, JR, with a focal lesion in left posterior superior and middle temporal gyrus. To test the necessity of this region in conceptual and perceptual processing of sound information we administered four different experimental tasks to JR: Visual word recognition, category fluency, sound recognition and voice classification. Compared with a matched control group, patient JR was consistently impaired in conceptual processing of sound-related everyday objects (e.g., "bell"), while performance for non-sound-related everyday objects (e.g., "armchair"), animals, whether they typically produce sounds (e.g., "frog") or not (e.g., "tortoise"), and musical instruments (e.g., "guitar") was intact. An analogous deficit pattern in JR was also obtained for perceptual recognition of the corresponding sounds. Hence, damage to left auditory association cortex specifically impairs perceptual and conceptual processing of sounds from everyday objects. In support of modality-specific theories, these findings strongly evidence the necessity of auditory association cortex in coding sound-related conceptual information.


Assuntos
Associação , Córtex Auditivo/fisiologia , Percepção Auditiva/fisiologia , Estimulação Acústica , Adulto , Animais , Córtex Auditivo/lesões , Córtex Auditivo/patologia , Epilepsia Generalizada/cirurgia , Humanos , Aprendizagem/fisiologia , Imageamento por Ressonância Magnética , Masculino , Música , Testes Neuropsicológicos , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Leitura , Reconhecimento Psicológico/fisiologia , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Voz , Testes de Associação de Palavras
10.
Eur Neuropsychopharmacol ; 23(10): 1270-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23219936

RESUMO

Models of addiction and addiction memory propose that drug-associated cues elicit incentive effects in drug users, which play an important role in maintenance of drug use and relapse. Incentive effects have been demonstrated for smoking and alcohol-related cues but evidence for heroin-related cues has been inconclusive. Furthermore, it is unknown whether appetitive effects of heroin-related cues persist after prolonged abstinence, although heroin addiction is known to have high relapse rates. Therefore, we investigated implicit and explicit valence of heroin-related cues in dependent users at different stages of abstinence using affective startle modulation. In Study I, 15 current heroin users were measured before and after detoxification. Correspondingly, 15 healthy control participants were tested twice at an interval of 14 days. In Study II, 14 long-term abstinent heroin users were additionally measured in a single session. Implicit processing of drug-related stimuli was assessed using affective startle modulation by pictures of heroin and smoking scenes. Explicit reactions were measured using ratings of valence and craving. In contrast to controls, heroin-dependent participants showed a clear reduction of startle response during heroin-related pictures (p<0.05). Detoxification did not significantly change their startle responses to heroin-cues. No difference between non-detoxified current and long-term abstinent heroin users was found in implicit reactions to heroin-cues, whereas explicit measures differed between both groups (all p<0.05). After detoxification and even after prolonged abstinence, heroin cues still exert implicit appetitive effects in heroin users. This implies that drug-induced adaptations of reward circuits are long-lasting, resulting in a highly stable addiction memory.


Assuntos
Comportamento Aditivo/prevenção & controle , Sinais (Psicologia) , Dependência de Heroína/terapia , Motivação , Estimulação Luminosa/efeitos adversos , Adulto , Analgésicos Opioides/uso terapêutico , Comportamento Aditivo/etiologia , Terapia Combinada , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Seguimentos , Dependência de Heroína/tratamento farmacológico , Dependência de Heroína/fisiopatologia , Dependência de Heroína/prevenção & controle , Humanos , Estudos Longitudinais , Masculino , Metadona/uso terapêutico , Tratamento de Substituição de Opiáceos , Fotografação , Reflexo de Sobressalto , Prevenção Secundária , Fatores de Tempo
11.
Brain Lang ; 122(2): 120-5, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22726721

RESUMO

Modality-specific models of conceptual memory propose close links between concepts and the sensory-motor systems. Neuroimaging studies found, in different subject groups, that action-related and sound-related concepts activated different parts of posterior middle temporal gyrus (pMTG), suggesting a modality-specific representation of conceptual features. However, as these different parts of pMTG are close to each other, it is possible that the observed anatomical difference is merely related to interindividual variability. In the present functional magnetic resonance imaging study, we now investigated within the same participant group a possible conceptual feature-specific organization in pMTG. Participants performed lexical decisions on sound-related (e.g., telephone) and action-related (hammer) words. Sound words elicited higher activity in anterior pMTG adjacent to auditory association cortex, but action-related words did so in posterior pMTG close to motion sensitive areas. These results confirm distinct conceptual representations of sound and action in pMTG, just adjacent to the respective modality-specific cortices.


Assuntos
Percepção Auditiva/fisiologia , Mapeamento Encefálico , Semântica , Som , Lobo Temporal/fisiologia , Estimulação Acústica , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Memória/fisiologia , Neuroimagem , Adulto Jovem
12.
Brain Res ; 1421: 52-65, 2011 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-21981803

RESUMO

Cognitive control can be adapted flexibly according to the conflict level in a given situation. In the Eriksen flanker task, interference evoked by flankers is larger in conditions with a higher, rather than a lower proportion of compatible trials. Such compatibility ratio effects also occur for stimuli presented at two spatial locations suggesting that different cognitive control settings can be simultaneously maintained. However, the conditions and the neural correlates of this flexible adaptation of cognitive control are only poorly understood. In the present study, we further elucidated the mechanisms underlying the simultaneous maintenance of two cognitive control settings. In behavioral experiments, stimuli were presented centrally above and below fixation and hence processed by both hemispheres or lateralized to stimulate hemispheres differentially. The different compatibility ratio at two stimulus locations had a differential influence on the flanker effect in both experiments. In an fMRI experiment, blocks with an identical compatibility ratio at two central spatial locations elicited stronger activity in a network of prefrontal and parietal brain areas, which are known to be involved in conflict resolution and cognitive control, as compared with blocks with a different compatibility ratio at the same spatial locations. This demonstrates that the simultaneous maintenance of two conflicting control settings vs. one single setting does not recruit additional neural circuits suggesting the involvement of one single cognitive control system. Instead a crosstalk between multiple control settings renders adaptation of cognitive control more efficient when only one uniform rather than two different control settings has to be simultaneously maintained.


Assuntos
Adaptação Psicológica/fisiologia , Mapeamento Encefálico , Encéfalo/fisiologia , Cognição/fisiologia , Negociação/psicologia , Adulto , Conflito Psicológico , Feminino , Lateralidade Funcional/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Análise e Desempenho de Tarefas , Adulto Jovem
13.
Neuroimage ; 56(3): 1714-25, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21356317

RESUMO

Professional musicians constitute a model par excellence for understanding experience-dependent plasticity in the human brain, particularly in the auditory domain. Their intensive sensorimotor experience with musical instruments has been shown to entail plastic brain alterations in cortical perceptual and motor maps. It remains an important question whether this neuroplasticity might extend beyond basic perceptual and motor functions and even shape higher-level conceptualizations by which we conceive our physical and social world. Here we show using functional magnetic resonance imaging (fMRI) that conceptual processing of visually presented musical instruments activates auditory association cortex encompassing right posterior superior temporal gyrus, as well as adjacent areas in the superior temporal sulcus and the upper part of middle temporal gyrus (pSTG/MTG) only in musicians, but not in musical laypersons. These areas in and adjacent to auditory association cortex were not only recruited by conceptual processing of musical instruments during visual object recognition, but also by auditory perception of real sounds. Hence, the unique intensive experience of musicians with musical instruments establishes a link between auditory perceptual and conceptual brain systems. Experience-driven neuroplasticity in musicians is thus not confined to alterations of perceptual and motor maps, but even leads to the establishment of higher-level semantic representations for musical instruments in and adjacent to auditory association cortex. These findings highlight the eminent importance of sensory and motor experience for acquiring rich concepts.


Assuntos
Música/psicologia , Plasticidade Neuronal/fisiologia , Adulto , Análise de Variância , Córtex Auditivo/fisiologia , Percepção Auditiva/fisiologia , Interpretação Estatística de Dados , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Ocupações , Estimulação Luminosa , Semântica
14.
Brain Lang ; 113(3): 103-12, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20156657

RESUMO

The human brain has the fascinating ability to represent and to process several languages. Although the first and further languages activate partially different brain networks, the linguistic factors underlying these differences in language processing have to be further specified. We investigated the neural correlates of language proficiency in a homogeneous sample of multilingual native Ladin speakers from a mountain valley in South Tyrol, Italy, who speak Italian as second language at a high level, and English at an intermediate level. In a constrained word production task under functional magnetic resonance imaging (fMRI), participants had to name pictures of objects in Ladin, Italian and English in separate blocks. Overall, multilingual word production activated a common set of brain areas dedicated to known subcomponents of picture naming. In comparison to English, the fluently spoken languages Ladin and Italian were associated with enhanced right prefrontal activity. In addition, the MR signal in right prefrontal cortex correlated with naming accuracy as a measure of language proficiency. Our results demonstrate the significance of right prefrontal areas for language proficiency. Based on the role of these areas for cognitive control, our findings suggest that right prefrontal cortex supports language proficiency by effectively supervising word retrieval.


Assuntos
Encéfalo/fisiologia , Idioma , Multilinguismo , Fala/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Lateralidade Funcional , Humanos , Itália , Testes de Linguagem , Imageamento por Ressonância Magnética , Masculino , Reconhecimento Visual de Modelos/fisiologia , Córtex Pré-Frontal/fisiologia , Vocabulário , Adulto Jovem
15.
Neuroimage ; 45(3): 1009-19, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19167505

RESUMO

Understanding the relevant meaning of a word with different meanings (homonym) in a given context requires activation of the neural representations of the relevant meaning and inhibition of the irrelevant meaning. The cognitive demand of such disambiguation is highest when the dominant, yet contextually irrelevant meaning of a polar homonym must be suppressed. This central process (semantic inhibition) for lexico-semantic ambiguity resolution was monitored with fMRI during semantic context verifications. Twenty-two healthy volunteers decided whether congruent or incongruent target words fitted into the contexts established by preceding sentences. Half of the sentences ended with a homonym, thereby allowing to cross the factors ambiguity and semantic congruency. BOLD increases related to the inhibitory attentional control over non-selected meanings during ambiguity processing occurred in a brain network including left dorsolateral prefrontal cortex (DLPFC), bilateral angular gyrus (AG), bilateral anterior superior temporal gyrus (aSTG) as well as right ventromedial temporal lobe. In left DLPFC (BA 46/9) and left AG (BA 39) BOLD activity to target words of the incongruent-ambiguous condition correlated with the individual amount of semantic interference experienced by the subjects. BOLD increases of incongruent versus congruent semantic verifications occurred in bilateral inferior frontal gyrus. The results of the present study suggest a specific role of left DLPFC and AG in the resolution of semantic interference from contextually inappropriate homonym meanings. These fronto-parietal areas might exert inhibitory control over temporal regions in service of attentional selection between relevant and irrelevant homonym meanings, by creating a sufficient activation difference between their respective representations.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Compreensão/fisiologia , Semântica , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
16.
J Neurosci ; 28(47): 12224-30, 2008 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-19020016

RESUMO

Traditionally, concepts are conceived as abstract mental entities distinct from perceptual or motor brain systems. However, recent results let assume modality-specific representations of concepts. The ultimate test for grounding concepts in perception requires the fulfillment of the following four markers: conceptual processing during (1) an implicit task should activate (2) a perceptual region (3) rapidly and (4) selectively. Here, we show using functional magnetic resonance imaging and recordings of event-related potentials, that acoustic conceptual features recruit auditory brain areas even when implicitly presented through visual words. Fulfilling the four markers, the findings of our study unequivocally link the auditory and conceptual brain systems: recognition of words denoting objects, for which acoustic features are highly relevant (e.g.,"telephone"), ignited cell assemblies in posterior superior and middle temporal gyri (pSTG/MTG) within 150 ms that were also activated by sound perception. Importantly, activity within a cluster of pSTG/MTG increased selectively as a function of acoustic, but not of visual and action-related feature relevance. The implicitness of the conceptual task, the selective modulation of left pSTG/MTG activity by acoustic feature relevance, the early onset of this activity at 150 ms and its anatomical overlap with perceptual sound processing are four markers for a modality-specific representation of auditory conceptual features in left pSTG/MTG. Our results therefore provide the first direct evidence for a link between perceptual and conceptual acoustic processing. They demonstrate that access to concepts involves a partial reinstatement of brain activity during the perception of objects.


Assuntos
Percepção Auditiva/fisiologia , Mapeamento Encefálico , Encéfalo/fisiologia , Formação de Conceito/fisiologia , Potenciais Evocados/fisiologia , Estimulação Acústica/métodos , Adulto , Encéfalo/anatomia & histologia , Encéfalo/irrigação sanguínea , Tomada de Decisões/fisiologia , Eletroencefalografia/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Oxigênio/sangue , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa/métodos , Tempo de Reação , Fatores de Tempo , Adulto Jovem
17.
J Cogn Neurosci ; 20(10): 1799-814, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18370598

RESUMO

Traditionally, concepts are assumed to be situational invariant mental knowledge entities (conceptual stability), which are represented in a unitary brain system distinct from sensory and motor areas (amodality). However, accumulating evidence suggests that concepts are embodied in perception and action in that their conceptual features are stored within modality-specific semantic maps in the sensory and motor cortex. Nonetheless, the first traditional assumption of conceptual stability largely remains unquestioned. Here, we tested the notion of flexible concepts using functional magnetic resonance imaging and event-related potentials (ERPs) during the verification of two attribute types (visual, action-related) for words denoting artifactual and natural objects. Functional imaging predominantly revealed crossover interactions between category and attribute type in visual, motor, and motion-related brain areas, indicating that access to conceptual knowledge is strongly modulated by attribute type: Activity in these areas was highest when nondominant conceptual attributes had to be verified. ERPs indicated that these category-attribute interactions emerged as early as 116 msec after stimulus onset, suggesting that they reflect rapid access to conceptual features rather than postconceptual processing. Our results suggest that concepts are situational-dependent mental entities. They are composed of semantic features which are flexibly recruited from distributed, yet localized, semantic maps in modality-specific brain regions depending on contextual constraints.


Assuntos
Encéfalo/fisiologia , Fertilização/fisiologia , Percepção de Movimento/fisiologia , Dinâmica não Linear , Recrutamento Neurofisiológico/fisiologia , Semântica , Adulto , Encéfalo/anatomia & histologia , Encéfalo/irrigação sanguínea , Mapeamento Encefálico , Eletroencefalografia/métodos , Potenciais Evocados Visuais/fisiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Oxigênio/sangue , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia
18.
Hippocampus ; 15(5): 597-609, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15884095

RESUMO

The medial temporal lobe (MTL) is well known to be crucial for various types of memory; however, controversy remains as to which of its substructures contribute to semantic processing and, if so, to what extent. The current study addresses the issue of MTL contributions to semantic processing during lexico-semantic ambiguity processing by using functional magnetic resonance imaging (fMRI) in combination with a context verification task (CVT). The CVT required decisions on the semantic fit of congruent and incongruent target words to the overall meaning of preceding sentential contexts with and without semantic ambiguity. In two of the four experimental conditions (congruent homographic, incongruent homographic), target decisions were critically dependent on the successful processing of prior sentence-final lexico-semantic ambiguity. Semantic context verification per se evidenced bilateral activations of the hippocampus that were part of a functional network including inferior prefrontal and superior parietal cortices. Commonalities in activation differences pertaining to the specific cognitive component of lexico-semantic ambiguity processing were found in a left temporal lobe network that comprised activation foci in the temporal pole, the parahippocampal and fusiform gyri. The present results suggest that the hippocampus may well contribute to semantic processing, namely by a mnemonic function that serves to link the target meaning representation with the meaning of a prior sentence context. Contrary to previous reports from human lesion studies, the present findings further suggest, that the specific cognitive component of lexico-semantic ambiguity processing is neither dependent on the hippocampus nor exclusively subserved by the temporal pole, but also recruits an associative semantic memory function from the parahippocampal gyrus as well as a more general (bottom-up) semantic function from the fusiform gyrus.


Assuntos
Aprendizagem por Associação/fisiologia , Hipocampo/fisiologia , Imageamento por Ressonância Magnética , Semântica , Lobo Temporal/fisiologia , Adulto , Cognição/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Giro Para-Hipocampal/fisiologia , Lobo Parietal/fisiologia , Estimulação Luminosa , Córtex Pré-Frontal/fisiologia
19.
Biol Psychiatry ; 57(10): 1153-8, 2005 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-15866555

RESUMO

BACKGROUND: Animal and clinical studies suggest that impaired sensorimotor gating, as assessed with the prepulse inhibition (PPI) paradigm, may result from dysfunctional frontostriatal brain circuits and from neurochemical alterations which are also implied in the pathophysiology of obsessive-compulsive disorder (OCD). However, there is only preliminary evidence about impaired PPI in OCD so far. METHODS: Acoustic PPI was measured in 30 OCD patients and 30 matched healthy controls with a paradigm using different prepulse intensities. Psychopathology assessment included ratings for obsessions, compulsions, and depression. RESULTS: PPI was reduced in OCD patients, and this deficit was most pronounced for most intense (16 dB(A)) prepulses, where mean PPI was 39.6% in unmedicated patients (n = 4), 45.8% in medicated patients, and 58.9% in controls. No group differences were observed with regard to the habituation of acoustic startle magnitude. Startle measures were generally not associated with clinical measures, although such associations may have been obscured by medication effects. CONCLUSIONS: The present study confirms deficient central inhibitory functioning in patients with OCD and supports the model of deficient frontostriatal circuits in OCD. The relationship of PPI deficits to pharmacological and behavioral treatment and to possible subtypes of OCD merits further study.


Assuntos
Transtorno Obsessivo-Compulsivo/fisiopatologia , Reflexo de Sobressalto/fisiologia , Estimulação Acústica , Adulto , Feminino , Humanos , Masculino , Rede Nervosa/fisiologia , Transtorno Obsessivo-Compulsivo/tratamento farmacológico , Transtorno Obsessivo-Compulsivo/psicologia , Escalas de Graduação Psiquiátrica
20.
Radiology ; 234(3): 860-8, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15650039

RESUMO

PURPOSE: To compare cortical activation patterns associated with manual motor decision tasks at 1.5- and 3.0-T functional magnetic resonance (MR) imaging. MATERIALS AND METHODS: The local ethics committee approved this study, and informed written consent was obtained. Ten right-handed healthy volunteers (eight men and two women; mean age, 35 years +/- 7 [standard deviation]) underwent functional MR imaging twice, once at 1.5 T and once at 3.0 T, while performing cognitive tasks that demanded manual motor decisions (letter-finger matching and lexical and semantic decisions). While stimulus presentation was blocked, an event-related model was employed to analyze subjects' individual responses. A group analysis of functional data was performed with a t test of 1.5- and 3.0-T results in the 10 subjects. RESULTS: Manual motor decisions activated a widespread network of motor- (primary motor, posterior parietal) and decision-related areas (superior frontal cortex or anterior cingulate) at both field strengths (P <.05, corrected). Moreover, additional functional activation was detected in medial (supplementary motor area) and dorsal premotor regions (P <.05, corrected) at 3.0-T functional MR imaging, which was not detectable with corresponding 1.5-T imaging. The mean t value for peak voxels in activated areas detectable with both systems was 1.3 times larger at 3.0 T than that at 1.5 T. CONCLUSION: Functional 3.0-T MR imaging allows detection of additional activation in cortical areas involved in higher executive motor functions compared with functional 1.5-T MR imaging.


Assuntos
Imageamento por Ressonância Magnética/métodos , Córtex Motor/fisiologia , Adulto , Mapeamento Encefálico , Imagem Ecoplanar , Feminino , Dedos/fisiologia , Lobo Frontal/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Destreza Motora/fisiologia
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