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1.
Behav Sci (Basel) ; 14(4)2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38667119

RESUMO

Inhibitory control performance may differ greatly as a function of individual differences such as anxiety. Nonetheless, how cognitive control proficiency might be influenced by exposure to various environments and how anxiety traits might impact these effects remain unexplored. A cohort of thirty healthy volunteers participated in the study. Participants performed a Go/No-Go task before exposure to a 'forest' and 'urban' virtual environment, in a counterbalanced design, before repeating the GNG task. The State-Trait Anxiety Inventory (STAI) was finally filled-in. Our findings unveiled an initial negative correlation between anxiety trait levels and GNG task performance, consistent with the established literature attributing difficulties in inhibitory functionality to anxiety. Additionally, different environmental exposures reported opposite trends. Exposure to the 'forest' environment distinctly improved the GNG performance in relation to anxiety traits, while the 'urban' setting demonstrated adverse effects on task performance. These results underscore the intricate relationship among cognitive control, environmental exposure, and trait anxiety. In particular, our findings highlight the potential of natural settings, such as forests, to mitigate the impact of anxiety on inhibition. This might have implications for interventions aimed at improving cognitive control.

2.
Children (Basel) ; 11(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38671636

RESUMO

This study investigated the associations among conduct problems, callous-unemotional (CU) traits, and indices of emotion recognition accuracy and emotion recognition bias obtained from human faces. Impairments in emotion recognition were considered within broader, impaired emotional and social functioning. The sample consisted of 293 middle-school students (51.19% girls; M age = 12.97 years, SD = 0.88 years). In general, CU traits were associated with less accuracy in recognizing emotions, especially fearful and angry faces, and such deficits in emotional recognition were not associated with conduct problems independent of CU traits. These results support the importance of studying potential deficits in the recognition of emotions other than fear. Furthermore, our results support the importance of considering the role of CU traits when studying emotional correlates of conduct problems. For children scoring high on CU traits, the emotion recognition accuracy of anger was low irrespective of the level of conduct problems, whereas in children scoring low on CU traits, less accuracy in recognizing emotions was related to increases in conduct problems. Finally, our results support the need for research to not only focus on accuracy of emotional recognition but also test whether there are specific biases leading to these inaccuracies. Specifically, CU traits were associated not only with lower accuracy in recognizing fearful faces but also with a tendency to interpret fearful faces as angry. This suggests that the emotional deficit associated with CU traits is not just a deficit in empathic concern toward others distress but also includes a tendency to overinterpret emotions as potential threats to oneself.

3.
Bioengineering (Basel) ; 11(4)2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38671829

RESUMO

Virtual reality (VR) can be a promising tool to simulate reality in various settings but the real impact of this technology on the human mental system is still unclear as to how VR might (if at all) interfere with cognitive functioning. Using a computer, we can concentrate, enter a state of flow, and still maintain control over our surrounding world. Differently, VR is a very immersive experience which could be a challenge for our ability to allocate divided attention to the environment to perform executive functioning tasks. This may also have a different impact on women and men since gender differences in both executive functioning and the immersivity experience have been referred to by the literature. The present study aims to investigate cognitive multitasking performance as a function of (1) virtual reality and computer administration and (2) gender differences. To explore this issue, subjects were asked to perform simultaneous tasks (span forward and backward, logical-arithmetic reasoning, and visuospatial reasoning) in virtual reality via a head-mounted display system (HDMS) and on a personal computer (PC). Our results showed in virtual reality an overall impairment of executive functioning but a better performance of women, compared to men, in visuospatial reasoning. These findings are consistent with previous studies showing a detrimental effect of virtual reality on cognitive functioning.

4.
Front Psychol ; 14: 1195668, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37809292

RESUMO

False memory formation is usually studied using the Deese-Roediger-McDermott paradigm (DRM), in which individuals incorrectly remember words that were not originally presented. In this paper, we systematically investigated how two modes of thinking (analytical vs. intuitive) can influence the tendency to create false memories. The increased propensity of intuitive thinkers to generate more false memories can be explained by one or both of the following hypotheses: a decrease in the inhibition of the lure words that come to mind, or an increased reliance on the familiarity heuristic to determine if the word has been previously studied. In two studies, we conducted tests of both recognition and recall using the DRM paradigm. Our observations indicate that a decrease in inhibitory efficiency plays a larger role in false memory formation compared to the use of the familiarity heuristic.

5.
Front Hum Neurosci ; 17: 1201898, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37600557

RESUMO

Pseudoneglect, the tendency to display a leftward perceptual bias, is consistently observed in line bisection tasks. Some studies have shown that pseudoneglect is sensitive to emotions. This emotion-related modulation is likely related to valence-dependent hemispheric lateralization, although the results do not converge. A possible explanation for these inconsistencies could be individual differences in emotional tone. Considering that negative and positive emotions produce different basic activations of the two hemispheres, emotional characteristics of the subjects, such as trait anxiety, could in fact modulate the pseudoneglect phenomenon. To verify this, high- and low-anxiety participants were asked to centrally bisect horizontal lines delimited by neutral or emotional (happy and sad) faces. In line with previous studies, results here showed a decrease in the leftward bisection error in the presence of happy faces, indicating a greater involvement of the left hemisphere in processing positive emotional stimuli. In addition, trait anxiety influenced the magnitude of the visual bias. High-anxiety subjects, compared to low-anxiety subjects, showed a general bias in visual attention toward the left space as a function of emotional valence. Results are discussed within the framework of valence-dependent hemispheric specialization and the relative degree of activation. In sum, our data highlight the relevance of considering emotional individual differences in studying the pseudoneglect phenomenon.

6.
Cogn Affect Behav Neurosci ; 23(2): 371-382, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36759426

RESUMO

Parkinson's disease (PD) is a neurodegenerative motor disorder that can associate with deficits in cognitive and emotional processing. In particular, PD has been reported to be mainly associated with defects in executive control and orienting attentional systems. The deficit in emotional processing mainly emerged in facial expression recognition. It is possible that the defects in emotional processing in PD may be secondary to other cognitive impairments, such as attentional deficits. This study was designed to systematically investigate the different weight of automatic and controlled attentional orienting mechanisms implied in emotional selective attention in PD. To address our purpose, we assessed drug-naïve PD patients and age-matched healthy controls with two dot-probe tasks that differed for stimuli duration. Automatic and controlled attentions were evaluated with stimuli lasting 100 ms and 500 ms, respectively. Furthermore, we introduced an emotion recognition task to investigate the performance in explicit emotion classification. The stimuli used in both the tasks dot-probe and emotion recognition were expressive faces displaying neutral, disgusted, fearful, and happy expressions.Our results showed that in PD patients, compared with healthy controls, there was 1) an alteration of automatic and controlled attentional orienting toward emotional faces in both the dot-probe tasks (with short and long durations), and 2) no difference in the emotion recognition task. These findings suggest that, from the early stages of the disease, PD can yield specific deficits in implicit emotion processing task (i.e., dot-probe task) despite a normal performance in explicit tasks that demand overt emotion recognition.


Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/psicologia , Expressão Facial , Emoções , Medo , Atenção
7.
J Sleep Res ; 31(3): e13527, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34854152

RESUMO

Previous studies suggest that sleep can influence false memories formation. Specifically, acute sleep loss has been shown to promote false memories production by impairing memory retrieval at subsequent testing. Surprisingly, the relationship between sleep and false memories has only been investigated in healthy subjects but not in individuals with insomnia, whose sleep is objectively impaired compared to healthy subjects. Indeed, this population shows several cognitive impairments involving prefrontal functioning that could affect source monitoring processes and contribute to false memories generation. Moreover, it has been previously reported that subjects with insomnia differentially process sleep-related versus neutral stimuli. Therefore, the aim of the present study was to compare false memories production between individuals with insomnia symptoms and good sleepers, and to evaluate the possible influence of stimulus category (neutral versus sleep-related) in the two groups. The results show that false memories are globally increased in participants reporting insomnia symptoms compared to good sleepers. A reduction in source monitoring ability was also observed in the former group, suggesting that an impairment of this executive function could be especially involved in false memories formation. Moreover, our data seem to confirm that false memories production in individuals with insomnia symptoms appears significantly modulated by stimulus category.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Humanos , Memória , Rememoração Mental , Repressão Psicológica , Sono
8.
Artigo em Inglês | MEDLINE | ID: mdl-33143327

RESUMO

The prolonged lockdown imposed to contain the COrona VIrus Disease 19 COVID-19 pandemic prevented many people from direct contact with nature and greenspaces, raising alarms for a possible worsening of mental health. This study investigated the effectiveness of a simple and affordable remedy for improving psychological well-being, based on audio-visual stimuli brought by a short computer video showing forest environments, with an urban video as a control. Randomly selected participants were assigned the forest or urban video, to look at and listen to early in the morning, and questionnaires to fill out. In particular, the State-Trait Anxiety Inventory (STAI) Form Y collected in baseline condition and at the end of the study and the Part II of the Sheehan Patient Rated Anxiety Scale (SPRAS) collected every day immediately before and after watching the video. The virtual exposure to forest environments showed effective to reduce perceived anxiety levels in people forced by lockdown in limited spaces and environmental deprivation. Although significant, the effects were observed only in the short term, highlighting the limitation of the virtual experiences. The reported effects might also represent a benchmark to disentangle the determinants of health effects due to real forest experiences, for example, the inhalation of biogenic volatile organic compounds (BVOC).


Assuntos
Infecções por Coronavirus/psicologia , Florestas , Saúde Mental/estatística & dados numéricos , Pandemias , Quarentena/psicologia , Estresse Psicológico/psicologia , Adulto , Idoso , Ansiedade/epidemiologia , Benchmarking , Betacoronavirus , COVID-19 , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Pneumonia Viral/epidemiologia , Pneumonia Viral/psicologia , SARS-CoV-2 , Estresse Fisiológico , Estresse Psicológico/epidemiologia , Gravação em Vídeo
9.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 3131-3134, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946551

RESUMO

The study of conformity from a neurobiological point of view has interested many authors: among them, Shestakova and colleagues (2013) have showed how conformity can be assessed through the analysis of event related potentials (ERPs). More specifically, the P300 component of the ERP was shown to be sensitive to the behavioral adjustment that an individual makes when not agreeing with the majority of a group. Starting from these contributions, in the present study, the famous experiment of Solomon Asch [1] was replicated online. The experiment was conducted on a sample of university students, using an innovative and low-cost tool capable of recording the brain signal (a wireless headset equipped with fourteen electrodes, called Emotiv EPOC). The present research aims to demonstrate how cheap and little sensitive tools enable the detection of ERP components that characterize social conformity in an ecological context.


Assuntos
Interfaces Cérebro-Computador , Eletroencefalografia , Eletroencefalografia/instrumentação , Potenciais Evocados P300 , Potenciais Evocados , Humanos , Conformidade Social
10.
J Abnorm Child Psychol ; 46(5): 1011-1019, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29046999

RESUMO

Callous-unemotional (CU) traits are associated with aggressive behavior but preliminary research suggests this relationship is modified by patterns of emotional processing. This study examined whether attentional orienting to emotional faces moderated the association between CU traits and peer-nominated aggression in 251 middle school students (53% females, mean age = 13.24 years, SD = 0.73). Attentional orienting was assessed using an emotional faces (i.e., angry, fearful, happy, sad, and neutral) variant of the dot-probe task. Students also completed a self-report measure of CU traits and their classmates made peer nominations of aggression. Logistic regression analyses showed that peer-nominated aggression was positively related to CU traits at low levels of attentional orienting to angry faces, whereas aggression was unrelated to CU traits at high levels of attentional orienting to angry faces. That is, peer-nominated aggression was greatest for youth high on CU traits who were not engaged by angry faces. These findings support the importance of considering different patterns of emotional responding when studying the association between CU traits and aggressive behavior in youth.


Assuntos
Agressão/fisiologia , Atenção/fisiologia , Emoções/fisiologia , Empatia/fisiologia , Expressão Facial , Reconhecimento Facial/fisiologia , Comportamento Social , Percepção Social , Adolescente , Criança , Feminino , Humanos , Masculino , Grupo Associado
11.
Int J Psychophysiol ; 106: 1-13, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27234617

RESUMO

The main goal of present work is to gain new insight into the temporal dynamics underlying the voluntary memory control for neutral faces associated with neutral, positive and negative contexts. A directed forgetting (DF) procedure was used during the recording of EEG to answer the question whether is it possible to forget a face that has been encoded within a particular emotional context. A face-scene phase in which a neutral face was showed in a neutral or emotional scene (positive, negative) was followed by the voluntary memory cue (cue phase) indicating whether the face had to-be remember or to-be-forgotten (TBR and TBF). Memory for faces was then assessed with an old/new recognition task. Behaviorally, we found that it is harder to suppress faces-in-positive-scenes compared to faces-in-negative and neutral-scenes. The temporal information obtained by the ERPs showed: 1) during the face-scene phase, the Late Positive Potential (LPP), which indexes motivated emotional attention, was larger for faces-in-negative-scenes compared to faces-in-neutral-scenes. 2) Remarkably, during the cue phase, ERPs were significantly modulated by the emotional contexts. Faces-in-neutral scenes showed an ERP pattern that has been typically associated to DF effect whereas faces-in-positive-scenes elicited the reverse ERP pattern. Faces-in-negative scenes did not show differences in the DF-related neural activities but larger N1 amplitude for TBF vs. TBR faces may index early attentional deployment. These results support the hypothesis that the pleasantness or unpleasantness of the contexts (through attentional broadening and narrowing mechanisms, respectively) may modulate the effectiveness of intentional memory suppression for neutral information.


Assuntos
Afeto/fisiologia , Atenção/fisiologia , Potenciais Evocados/fisiologia , Rememoração Mental/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Adulto , Eletroencefalografia , Reconhecimento Facial/fisiologia , Feminino , Humanos , Intenção , Masculino , Reconhecimento Psicológico/fisiologia , Adulto Jovem
12.
Neurol Sci ; 37(1): 97-104, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26298827

RESUMO

Huntington's disease (HD) primarily affects striatum and prefrontal dopaminergic circuits which are fundamental neural correlates of the timekeeping mechanism. The few studies on HD mainly investigated motor timing performance in second durations. The present work explored time perception in early-to-moderate symptomatic HD patients for seconds and milliseconds with the aim to clarify which component of the scalar expectancy theory (SET) is mainly responsible for HD timing defect. Eleven HD patients were compared to 11 controls employing two separate temporal bisection tasks in second and millisecond ranges. Our results revealed the same time perception deficits for seconds and milliseconds in HD patients. Time perception impairment in early-to-moderate stages of Huntington's disease is related to memory deficits. Furthermore, both the non-systematical defect of temporal sensitivity and the main impairment of timing performance in the extreme value of the psychophysical curves suggested an HD deficit in the memory component of the SET. This result was further confirmed by the significant correlations between time perception performance and long-term memory test scores. Our findings added important preliminary data for both a deeper comprehension of HD time-keeping deficits and possible implications on neuro-rehabilitation practices.


Assuntos
Doença de Huntington/complicações , Doença de Huntington/psicologia , Transtornos da Memória/complicações , Percepção do Tempo , Feminino , Humanos , Doença de Huntington/diagnóstico , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Psicofísica , Índice de Gravidade de Doença
13.
Acta Psychol (Amst) ; 159: 1-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26000956

RESUMO

The emotional influence of facial expressions on memory is well-known whereas the influence of emotional contextual information on memory for emotional faces is yet to be extensively explored. This study investigated the interplay between facial expression and the emotional surrounding context in affecting both memory for identities (item memory) and memory for associative backgrounds (source memory). At the encoding fearful and happy faces were presented embedded in fear or happy scenes (i.e.: fearful faces in fear-scenes, happy faces in happy-scenes, fearful faces in happy-scenes and happy faces in fear-scenes) and participants were asked to judge the emotional congruency of the face-scene compounds (i.e. fearful faces in fear-scenes and happy faces in happy-scenes were congruent compounds). In the recognition phase, the old faces were intermixed with the new ones: all the faces were presented isolated with a neutral expression. Participants were requested to indicate whether each face had been previously presented (item memory). Then, for each old face the memory for the scene originally compounded with the face was tested by a three alternative forced choice recognition task (source memory). The results evidenced that face identity memory is differently modulated by the valence in congruent face-context compounds with better identity recognition (item memory) for happy faces encoded in happy-scenarios. Moreover, also the memory for the surrounding context (source memory) benefits from the association with a smiling face. Our findings highlight that socially positive signals conveyed by smiling faces may prompt memory for identity and context.


Assuntos
Expressão Facial , Reconhecimento Facial/fisiologia , Memória Episódica , Reconhecimento Psicológico/fisiologia , Percepção Social , Adulto , Medo , Feminino , Felicidade , Humanos , Masculino , Sorriso , Adulto Jovem
14.
Int J Psychophysiol ; 91(3): 240-53, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24417862

RESUMO

The relation between attractiveness and motor affordance is a key topic in design and has not yet been investigated electrophysiologically. In this respect, action affordance and attractiveness represent two crucial dimensions in object processing (specifically for tools). In light of this evidence, Event Related Potentials (ERPs) enabled us to gain new insights into the time course of the interaction between these two dimensions during an explicit tool evaluation task. Behaviorally, tools that were judged as high affording and high attractive yielded faster response times than those judged as low affording and low attractive. The ERP results showed that early processes related to sensory gating and feature extraction (N100) were sensitive to both affordance and attractiveness; the P200 was dominated by affordance, indexing a facilitated access to motor action representation. The N300, P300 and the Late Positive Potential (LPP) showed enhanced responses for highly affording/attractive tools, reflecting the interconnection between attractiveness and affordance. Later responses were entirely affected by attractiveness, suggesting additional affective responses evoked by desirable tools. We are showing that things that are perceived as more functional and attractive have a privileged neural activation in the time course of tool evaluation, for the first time.


Assuntos
Potenciais Evocados/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Análise de Variância , Eletroencefalografia , Feminino , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação/fisiologia , Adulto Jovem
15.
Front Psychol ; 4: 1001, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24427152

RESUMO

The question that motivated this study was to investigate the relation between trait anxiety, emotions and memory control. To this aim, memory suppression was explored in high and low trait anxiety individuals with the Think/No-think paradigm. After learning associations between neutral words and emotional scenes (negative, positive, and neutral), participants were shown a word and were requested either to think about the associated scene or to block it out from mind. Finally, in a test phase, participants were again shown each word and asked to recall the paired scene. The results show that memory control is influenced by high trait anxiety and emotions. Low trait anxiety individuals showed a memory suppression effect, whereas there was a lack of memory suppression in high trait anxious individuals, especially for emotionally negative scenes. Thus, we suggest that individuals with anxiety may have difficulty exerting cognitive control over memories with a negative valence. These findings provide evidence that memory suppression can be impaired by anxiety thus highlighting the crucial relation between cognitive control, emotions, and individual differences in regulating emotions.

16.
Soc Cogn Affect Neurosci ; 9(1): 63-72, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22956674

RESUMO

We used event-related potentials (ERPs) to tap the temporal dynamics of first impressions based on face appearance. Participants were asked to evaluate briefly presented faces for trustworthiness and political choice. Behaviorally, participants were better at discriminating faces that were pre-rated as untrustworthy. The ERP results showed that the P100 component was enhanced for untrustworthy faces, consistently with the view that signals of potential threat are given precedence in neural processing. The enhanced ERP responses to untrustworthy faces persisted throughout the processing sequence and the amplitude of early posterior negativity (EPN), and subsequent late positive potential (LPP) was increased with respect to trustworthy faces which, in contrast, elicited an enhanced positivity around 150 ms on frontal sites. These ERP patterns were found specifically for the trustworthiness evaluation and not for the political decision task. Political decision yielded an increase in the N170 amplitude, reflecting a more demanding and taxing structural encoding. Similar ERP responses, as previously reported in the literature for facial expressions processing, were found throughout the entire time course specifically elicited by faces explicitly judged as untrustworthy. One possibility might be that evolution has provided the brain with a 'special toolkit' for trust evaluation that is fast and triggers ERPs related to emotional processing.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Potenciais Evocados/fisiologia , Confiança , Adulto , Análise de Variância , Eletroencefalografia , Emoções/fisiologia , Face , Expressão Facial , Feminino , Humanos , Julgamento , Masculino , Reconhecimento Visual de Modelos , Estimulação Luminosa , Tempo de Reação/fisiologia , Adulto Jovem
17.
Cortex ; 48(9): 1128-37, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21757194

RESUMO

Previous studies indicate that extinguished stimuli can still be unconsciously processed, leading to implicit priming effects. Here we investigated whether these implicit effects might be modulated by the semantic nature of the stimuli. Five neglect patients and ten controls performed an identification task of items belonging to living and non-living categories. In the study phase photographs of animals and artifacts were presented either to the left visual field (LVF) or to the right visual field (RVF). In the identification phase, each stimulus was displayed centrally and was revealed in a sequence of frames where the item was represented by an increasingly less and less filtered image up to a complete version. The results showed that lateralized stimuli differentially affected controls' and neglect patients' memory retrieval. In controls memory traces from the study phase served as efficient primes, thereby reducing the amount of information necessary for the identification of both stimulus categories. Moreover, hemispheric differences emerged with an advantage of the RVF/left hemisphere for artifact items, while no difference was found for living things. Neglect patients showed a priming effect for artifact items presented either to the RVF/left hemisphere or LVF/right hemisphere, as well as for living items presented to the RVF/left hemisphere, but not for living items presented to the LVF/right hemisphere. The priming effect observed for extinguished artifacts is consistent with the evidence of the existence of a specific mechanism destined to analyze, in an automatic and implicit fashion, motor-relevant information of manipulable objects and tools, which are important for identification process. Results are discussed in relation to current models of organization of conceptual knowledge within the framework of different processes performed by the two hemispheres.


Assuntos
Córtex Cerebral/fisiopatologia , Semântica , Campos Visuais/fisiologia , Percepção Visual/fisiologia , Idoso , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Memória/fisiologia , Pessoa de Meia-Idade , Análise e Desempenho de Tarefas
18.
Exp Brain Res ; 207(3-4): 213-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20972777

RESUMO

Alpha waves are traditionally considered a passive consequence of the lack of stimulation of sensory areas. However, recent results have challenged this view by showing a modulation of alpha activity in cortical areas representing unattended information during active tasks. These data have led us to think that alpha waves would support a 'gating function' on sensorial stimulation that actively inhibits unattended information in attentional tasks. Visual suppression occurring during a saccade and blink entails an inhibition of incoming visual information, and it seems to occur at an early processing stage. In this study, we hypothesized that the neural mechanism through which the visual system exerts this inhibition is the active imposition of alpha oscillations in the occipital cortex, which in turn predicts an increment of alpha amplitude during a visual suppression phenomena. We measured visual suppression occurring during short closures of the eyelids, a situation well suited for EEG recordings and stimulated the retinae with an intra-oral light administered through the palate. In the behavioral experiment, detection thresholds were measured with eyes steady open and steady closed, showing a reduction of sensitivity in the latter case. In the EEG recordings performed under identical conditions we found stronger alpha activity with closed eyes. Since the stimulation does not depend on whether the eyes were open or closed, we reasoned that this should be a central effect, probably due to a functional role of alpha oscillation in agreement with the 'gating function' theory.


Assuntos
Ritmo alfa/fisiologia , Inibição Neural/fisiologia , Córtex Visual/fisiologia , Percepção Visual/fisiologia , Relógios Biológicos/fisiologia , Mapeamento Encefálico/métodos , Eletroencefalografia/métodos , Humanos , Estimulação Luminosa/métodos , Movimentos Sacádicos/fisiologia , Adulto Jovem
19.
J Anxiety Disord ; 23(8): 1132-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19695828

RESUMO

The relation between anxiety, cognitive self-evaluation, performance, and electrical brain activity (event-related potentials, ERPs) in a sustained attention task (Go/NoGo; SART) was investigated in 18 participants. No significant correlation was found between reaction times and anxiety (assessed by State and Trait Anxiety Inventory or STAI), and cognitive self-evaluation (assessed by Cognitive Failures Questionnaire or CFQ). N2 (ERP time-window 250-350ms) and P3 (350-650ms) amplitudes were found to be related to anxiety and cognitive self-evaluation. N2 amplitude increased in trait and state high anxious participants, whereas P3 decreased in participants who reported a higher frequency of cognitive failures. Electrophysiological responses revealed that cognitive strategies were probably activated by more anxious and less self-confident individuals in order to be efficient in their performance. As shown by current research, frontal areas and anterior cingulated cortex appear to be particularly involved in this affective-cognitive interaction.


Assuntos
Transtornos de Ansiedade/fisiopatologia , Nível de Alerta/fisiologia , Atenção/fisiologia , Cognição/fisiologia , Eletroencefalografia , Potenciais Evocados/fisiologia , Inibição Psicológica , Reconhecimento Visual de Modelos/fisiologia , Desempenho Psicomotor/fisiologia , Autoimagem , Adulto , Transtornos de Ansiedade/diagnóstico , Transtornos de Ansiedade/psicologia , Mapeamento Encefálico , Córtex Cerebral/fisiologia , Dominância Cerebral/fisiologia , Feminino , Lobo Frontal/fisiopatologia , Giro do Cíngulo/fisiopatologia , Humanos , Inventário de Personalidade/estatística & dados numéricos , Psicometria , Tempo de Reação/fisiologia , Processamento de Sinais Assistido por Computador , Adulto Jovem
20.
Exp Aging Res ; 34(3): 267-81, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18568983

RESUMO

There is considerable evidence that visual recognition memory is largely affected by Alzheimer's disease (AD). Deficits might concern the forming, maintaining, and matching of the memory representation of the visual stimulus, especially when long interitem lags occur. The aim of the present study was to assess the effect of repetition lag on picture identification in mild- and moderate-AD patients, as well as in elderly controls. Participants underwent an old/new paradigm. To manipulate the temporal gradient, short and long lags were introduced between the first and second presentations. Pictures were presented at different levels of spatial filtering, following a coarse-to-fine order. This allowed for the measurement of the amount of physical information required for the identification of stimuli as a function of prior exposure and repetition lag. In the elderly, the magnitude of repetition priming did not differ as a function of interitem lag. Instead, repetition-lag effects interacted with dementia severity, and the capacity to retain memory traces for longer intervals worsened as the disease progresses. Current findings suggest that severe cortical degeneration may render AD patients unable to maintain their perceptual memories, and that dementia severity is a critical variable in the visual recognition memory assessment.


Assuntos
Doença de Alzheimer/psicologia , Reconhecimento Visual de Modelos , Retenção Psicológica , Transferência de Experiência , Idoso , Amnésia/psicologia , Sinais (Psicologia) , Demência/psicologia , Progressão da Doença , Feminino , Humanos , Masculino , Entrevista Psiquiátrica Padronizada , Estimulação Luminosa , Prática Psicológica , Reconhecimento Psicológico , Limiar Sensorial , Enquadramento Psicológico , Fatores de Tempo
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