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1.
PLoS One ; 19(1): e0297480, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38232113

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0294805.].

2.
Neuropsychol Rev ; 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36967445

RESUMO

Attention, working memory, and executive control are commonly considered distinct cognitive functions with important reciprocal interactions. Yet, longstanding evidence from lesion studies has demonstrated both overlap and dissociation in their behavioural expression and anatomical underpinnings, suggesting that a lower dimensional framework could be employed to further identify processes supporting goal-directed behaviour. Here, we describe the anatomical and functional correspondence between attention, working memory, and executive control by providing an overview of cognitive models, as well as recent data from lesion studies, invasive and non-invasive multimodal neuroimaging and brain stimulation. We emphasize the benefits of considering converging evidence from multiple methodologies centred on the identification of brain mechanisms supporting goal-driven behaviour. We propose that expanding on this approach should enable the construction of a comprehensive anatomo-functional framework with testable new hypotheses, and aid clinical neuroscience to intervene on impairments of executive functions.

3.
Neuropsychologia ; 170: 108228, 2022 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-35358537

RESUMO

When we see someone's face, our brain usually effortlessly extracts a variety of information such as facial identity, expression, or gaze direction. While it is widely accepted that dedicated subsystems are responsible for different aspects of face processing, how these subsystems work together is not yet fully understood. To this extent, one of the most explored questions is whether and if so, to what extent facial expression processing interacts with other stages of facial processing. In the present study, we report a rare case of a patient for whom we were able to record multi-unit activity (MUA) in the proximity of the fusiform face area (FFA) while two out of four recorded multi-units were face-selective. In our experiment, the human subject was shown images of neutral and fearful faces as well as everyday objects and frightening images of natural disaster. We found that activity of both face-selective units was modulated by facial expression stimuli, starting at about 150 ms from stimulus onset. For both facial conditions we observed abrupt increase in firing rate with a simultaneous peak, suggesting that this activity and the modulation by facial expression stimuli likely reflected feed-forward processing. Interestingly, while in one multi-unit, the firing rate for fearful faces was higher than for neutral faces, in the other multi-units the polarity was reversed. Finally, modulation in the face-selective units was specific to emotional facial stimuli, but not to emotional stimuli in general. The present multi-unit results, albeit obtained only for several multi-units, nevertheless are potentially valuable for understanding mechanisms of facial processing in humans.


Assuntos
Encéfalo , Expressão Facial , Mapeamento Encefálico , Emoções , Medo , Humanos
5.
J Cogn Neurosci ; 26(9): 2155-70, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24666125

RESUMO

Patients with unilateral spatial neglect (USN) often show impaired performance in spatial working memory tasks, apart from the difficulty retrieving "left-sided" spatial data from long-term memory, shown in the "piazza effect" by Bisiach and colleagues. This study's aim was to compare the effect of the spatial position of a visual object on immediate and delayed memory performance in USN patients. Specifically, immediate verbal recall performance, tested using a simultaneous presentation of four visual objects in four quadrants, was compared with memory in a later-provided recognition task, in which objects were individually shown at the screen center. Unlike healthy controls, USN patients showed a left-side disadvantage and a vertical bias in the immediate free recall task (69% vs. 42% recall for right- and left-sided objects, respectively). In the recognition task, the patients correctly recognized half of "old" items, and their correct rejection rate was 95.5%. Importantly, when the analysis focused on previously recalled items (in the immediate task), no statistically significant difference was found in the delayed recognition of objects according to their original quadrant of presentation. Furthermore, USN patients were able to recollect the correct original location of the recognized objects in 60% of the cases, well beyond chance level. This suggests that the memory trace formed in these cases was not only semantic but also contained a visuospatial tag. Finally, successful recognition of objects missed in recall trials points to formation of memory traces for neglected contralesional objects, which may become accessible to retrieval processes in explicit memory.


Assuntos
Lateralidade Funcional/fisiologia , Transtornos da Memória/etiologia , Rememoração Mental/fisiologia , Transtornos da Percepção/complicações , Reconhecimento Psicológico/fisiologia , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Mapeamento Encefálico , Distribuição de Qui-Quadrado , Feminino , Hemorragia/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos da Percepção/etiologia , Transtornos da Percepção/patologia , Estimulação Luminosa , Radiografia , Acidente Vascular Cerebral/complicações , Fatores de Tempo , Aprendizagem Verbal/fisiologia
6.
J Vis ; 12(6)2012 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-22728679

RESUMO

Accurately perceiving the velocity of an object during smooth pursuit is a complex challenge: although the object is moving in the world, it is almost still on the retina. Yet we can perceive the veridical motion of a visual stimulus in such conditions, suggesting a nonretinal representation of the motion vector. To explore this issue, we studied the frames of representation of the motion vector by evoking the well known motion aftereffect during smooth-pursuit eye movements (SPEM). In the retinotopic configuration, due to an accompanying smooth pursuit, a stationary adapting random-dot stimulus was actually moving on the retina. Motion adaptation could therefore only result from motion in retinal coordinates. In contrast, in the spatiotopic configuration, the adapting stimulus moved on the screen but was practically stationary on the retina due to a matched SPEM. Hence, adaptation here would suggest a representation of the motion vector in spatiotopic coordinates. We found that exposure to spatiotopic motion led to significant adaptation. Moreover, the degree of adaptation in that condition was greater than the adaptation induced by viewing a random-dot stimulus that moved only on the retina. Finally, pursuit of the same target, without a random-dot array background, yielded no adaptation. Thus, in our experimental conditions, adaptation is not induced by the SPEM per se. Our results suggest that motion computation is likely to occur in parallel in two distinct representations: a low-level, retinal-motion dependent mechanism and a high-level representation, in which the veridical motion is computed through integration of information from other sources.


Assuntos
Adaptação Fisiológica/fisiologia , Pós-Efeito de Figura/fisiologia , Percepção de Movimento/fisiologia , Acompanhamento Ocular Uniforme/fisiologia , Retina/fisiologia , Adulto , Feminino , Humanos , Masculino , Modelos Neurológicos , Estimulação Luminosa/métodos , Adulto Jovem
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