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1.
PLoS One ; 18(1): e0279881, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36689427

RESUMO

Stimulus-induced narrow-band gamma oscillations (30-70 Hz) in human electro-encephalograph (EEG) have been linked to attentional and memory mechanisms and are abnormal in mental health conditions such as autism, schizophrenia and Alzheimer's Disease. However, since the absolute power in EEG decreases rapidly with increasing frequency following a "1/f" power law, and the gamma band includes line noise frequency, these oscillations are highly susceptible to instrument noise. Previous studies that recorded stimulus-induced gamma oscillations used expensive research-grade EEG amplifiers to address this issue. While low-cost EEG amplifiers have become popular in Brain Computer Interface applications that mainly rely on low-frequency oscillations (< 30 Hz) or steady-state-visually-evoked-potentials, whether they can also be used to measure stimulus-induced gamma oscillations is unknown. We recorded EEG signals using a low-cost, open-source amplifier (OpenBCI) and a traditional, research-grade amplifier (Brain Products GmbH), both connected to the OpenBCI cap, in male (N = 6) and female (N = 5) subjects (22-29 years) while they viewed full-screen static gratings that are known to induce two distinct gamma oscillations: slow and fast gamma, in a subset of subjects. While the EEG signals from OpenBCI were considerably noisier, we found that out of the seven subjects who showed a gamma response in Brain Products recordings, six showed a gamma response in OpenBCI as well. In spite of the noise in the OpenBCI setup, the spectral and temporal profiles of these responses in alpha (8-13 Hz) and gamma bands were highly correlated between OpenBCI and Brain Products recordings. These results suggest that low-cost amplifiers can potentially be used in stimulus-induced gamma response detection.


Assuntos
Eletroencefalografia , Potenciais Evocados , Humanos , Masculino , Feminino , Eletroencefalografia/métodos , Encéfalo/fisiologia , Mapeamento Encefálico/métodos , Ruído
2.
BMC Psychiatry ; 23(1): 19, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36624426

RESUMO

BACKGROUND: Decision-making deficits have been reported in suicide attempters and may be a neuropsychological trait of vulnerability to suicidal behavior. However, little is known about how neural activity is altered in decision-making. This study aimed to investigate the neural responses in suicide attempters with mental disorders during social decision-making. Electroencephalography (EEG) were recorded from 52 patients with mental disorders with past suicide attempts (SAs = 26) and without past suicide attempts (NSAs = 26), as well as from 22 age- and sex- matched healthy controls (HCs) during the Ultimatum Game (UG), which is a typical paradigm to investigate the responses to fair and unfair decision-making. METHODS: MINI 5.0 interview and self report questionnaire were used to make mental diagnosis and suicide behavior assessment for individuals. Event-related potential (ERP) and phase-amplitude coupling (PAC) were extracted to quantify the neural activity. Furthermore, Spearman correlation and logistic regression analyses were conducted to identify the risk factors of suicidal behavior. RESULTS: ERP analysis demonstrated that SA patients had decreased P2 amplitude and prolonged P2 latency when receiving unfair offers. Moreover, SA patients exhibited greater negative-going feedback-related negativity (FRN) to unfair offers compared to fair ones, whereas such a phenomenon was absent in NSA and HC groups. These results revealed that SA patients had a stronger fairness principle and a disregard toward the cost of punishment in social decision-making. Furthermore, theta-gamma and beta-gamma PAC were involved in decision-making, with compromised neural coordination in the frontal, central, and temporal regions in SA patients, suggesting cognitive dysfunction during social interaction. Statistically significant variables were used in logistic regression analysis. The area under receiver operating characteristic curve in the logistic regression model was 0.91 for SA/HC and 0.84 for SA/NSA. CONCLUSIONS: Our findings emphasize that suicide attempts in patients with mental disorders are associated with abnormal decision-making. P2, theta-gamma PAC, and beta-gamma PAC may be neuro-electrophysiological biomarkers associated with decision-making. These results provide neurophysiological signatures of suicidal behavior.


Assuntos
Disfunção Cognitiva , Tentativa de Suicídio , Humanos , Tentativa de Suicídio/psicologia , Ideação Suicida , Potenciais Evocados , Eletroencefalografia , Tomada de Decisões
3.
PeerJ ; 11: e14583, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36632142

RESUMO

Emotional categorisation (deciding whether a word is emotional or not) is a task that employs the explicit analysis of the emotional meaning of words. Therefore, it allows for assessing the role of emotional factors, i.e., valence, arousal, and subjective significance, in emotional word processing. The aim of the current experiment was to investigate the role of subjective significance, a reflective form of activation that is similar to arousal (the automatic form), in the processing of emotional meaning. We applied the orthogonal manipulation of three emotional factors. Thus, we were able to precisely differentiate the effects of each factor and search for interactions between them. We expected valence to shape the late positive complex LPC component, while subjective significance and arousal were expected to shape the P300 and N400 components. We observed the effects of subjective significance throughout the whole span of processing, while the arousal effect was present only in the LPC component. We also observed that amplitudes for N400 and LPC discriminated negative from positive valence. The results showed that all factors included in the analysis should be taken into account while explaining the processing of emotion-laden words; especially interesting is the subjective significance, which was shown to shape processing individually, as well as to come into interaction with valence and arousal.


Assuntos
Eletroencefalografia , Potenciais Evocados , Humanos , Masculino , Feminino , Potenciais Evocados/fisiologia , Emoções/fisiologia , Nível de Alerta/fisiologia
4.
Int J Psychophysiol ; 184: 100-109, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36638913

RESUMO

BACKGROUND: The error-related negativity (ERN) reflects individual differences in error monitoring. However, findings on the ERN in adult and adolescent depression have been inconsistent. Analyzing electroencephalographic (EEG) data in both the time- and time-frequency domain can be useful to better quantify neural response to errors. The present study aimed at examining electrocortical measures of error monitoring in early adolescents with and without depression. METHOD: EEG activity was collected during an arrowhead version of the flanker task in 29 (25 females) early adolescents with depression and 34 without MDD (29 females). RESULTS: The depression group showed reduced ERN amplitude, reduced error-related theta power and increased error-related beta power compared to the control group. When all variables that related to MDD diagnosis were considered simultaneously, both theta and beta power, but not the ERN, were independently related to an increased likelihood of being diagnosed with depression. CONCLUSIONS: By examining both time-domain and separate time-frequency measures, the present study provided novel evidence on error monitoring alterations in youth depression, suggesting that depression during adolescence may be characterized by reduced error monitoring (i.e., reduced ERN and error-related theta) and post-error inhibition (i.e., greater error-related beta power). These results support that time-frequency measures might be better suited for examining error-related neural activity in MDD relative to time-domain measures.


Assuntos
Transtorno Depressivo Maior , Adulto , Feminino , Adolescente , Humanos , Criança , Eletroencefalografia , Encéfalo , Potenciais Evocados/fisiologia
5.
J Vis ; 23(1): 10, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36652236

RESUMO

Task-irrelevant threatening faces (e.g., fearful) are difficult to filter from visual working memory (VWM), but the difficulty in filtering non-threatening negative faces (e.g., sad) is not known. Depressive symptoms could also potentially affect the ability to filter different emotional faces. We tested the filtering of task-irrelevant sad and fearful faces by depressed and control participants performing a color-change detection task. The VWM storage of distractors was indicated by contralateral delay activity, a specific event-related potential index for the number of objects stored in VWM during the maintenance phase. The control group did not store sad face distractors, but they automatically stored fearful face distractors, suggesting that threatening faces are specifically difficult to filter from VWM in non-depressed individuals. By contrast, depressed participants showed no additional consumption of VWM resources for either the distractor condition or the non-distractor condition, possibly suggesting that neither fearful nor sad face distractors were maintained in VWM. Our control group results confirm previous findings of a threat-related filtering difficulty in the normal population while also suggesting that task-irrelevant non-threatening negative faces do not automatically load into VWM. The novel finding of the lack of negative distractors within VWM storage in participants with depressive symptoms may reflect a decreased overall responsiveness to negative facial stimuli. Future studies should investigate the mechanisms underlying distractor filtering in depressed populations.


Assuntos
Medo , Memória de Curto Prazo , Humanos , Emoções , Potenciais Evocados
6.
PLoS One ; 18(1): e0278826, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36662726

RESUMO

Mindfulness-based stress reduction (MBSR) training has been shown to improve cognitive processing, wellbeing, and academic performance. However, mindfulness interventions that are integrated into non-mindfulness related courses have not been well-investigated. Further, the unique effects of different aspects of MBSR training are not as well understood. This paper examines the effects that are uniquely associated with focused-attention versus self-compassion mindfulness practices utilizing a multi-method approach. Event-related potentials (ERPs) were recorded during an Emotional Flanker task, and self-report measures of wellbeing and measures of classroom performance were collected before and after training. Participants were students in two sections of the same undergraduate course and either completed 10 weeks of focused-attention practice or self-compassion practice that was built into their class sessions. Students in the focused-attention group (mean age = 22.08) had reduced interference effects on their reaction times following the training. Students in the self-compassion group (mean age = 23.91) showed altered processing of conflict on negative trials via the N2 and P3 ERP amplitudes after the training. This group also reported significant improvements in wellbeing and performed significantly better on more class tests compared to the focused-attention group. These data support the effectiveness of incorporating brief, simplified mindfulness practices in any classroom as an intervention to improve attention, wellbeing and classroom performance.


Assuntos
Meditação , Humanos , Adulto Jovem , Adulto , Meditação/psicologia , Autocompaixão , Autorrelato , Estresse Psicológico/prevenção & controle , Estresse Psicológico/psicologia , Estudantes/psicologia , Atenção , Potenciais Evocados
7.
PLoS One ; 18(1): e0269326, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36662730

RESUMO

The pitch perturbation technique is a validated technique that has been used for over 30 years to understand how people control their voice. This technique involves altering a person's voice pitch in real-time while they produce a vowel (commonly, a prolonged /a/ sound). Although post-task changes in the voice have been observed in several studies (e.g., a change in mean fo across the duration of the experiment), the potential for using the pitch perturbation technique as a training tool for voice pitch regulation and/or modification has not been explored. The present study examined changes in event related potentials (ERPs) and voice pitch in three groups of subjects due to altered voice auditory feedback following a brief, four-day training period. Participants in the opposing group were trained to change their voice fo in the opposite direction of a pitch perturbation stimulus. Participants in the following group were trained to change their voice fo in the same direction as the pitch perturbation stimulus. Participants in the non-varying group did not voluntarily change their pitch, but instead were asked to hold their voice constant when they heard pitch perturbations. Results showed that all three types of training affected the ERPs and the voice pitch-shift response from pre-training to post-training (i.e., "hold your voice pitch steady" task; an indicator of voice pitch regulation). Across all training tasks, the N1 and P2 components of the ERPs occurred earlier, and the P2 component of the ERPs occurred with larger amplitude post-training. The voice responses also occurred earlier but with a smaller amplitude following training. These results demonstrate that participation in pitch-shifted auditory feedback tasks even for brief periods of time can modulate the automatic tendency to compensate for alterations in voice pitch feedback and has therapeutic potential.


Assuntos
Eletroencefalografia , Voz , Humanos , Treinamento da Voz , Retroalimentação , Percepção da Altura Sonora/fisiologia , Potenciais Evocados/fisiologia , Voz/fisiologia , Retroalimentação Sensorial/fisiologia
8.
Brain Lang ; 236: 105218, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36571932

RESUMO

Inconsistent information can be hard to understand, but in cases like fiction readers can integrate it with little to no difficulties. The present study aimed at examining if perspective switching can take place when only a minimal fictional description is provided (fictional world condition), as compared with general world knowledge (real world condition). Participants read sentences where food items had animated or inanimate features while EEG was recorded and performed a sentence completion task to evaluate recall. In the real-world condition, the N400 was significantly larger for sentences incongruent, rather than congruent, with general world knowledge. In the fictional world condition, the N400 elicited by congruent and incongruent sentences did not differ, confirming that the minimal description impacted online information processing. Information consistent with general knowledge was better recalled in both conditions. The current results highlight how contextual information is integrated during sentence comprehension.


Assuntos
Queijo , Eletroencefalografia , Humanos , Masculino , Feminino , Potenciais Evocados , Ciúme , Compreensão , Semântica
9.
Neurosci Lett ; 792: 136957, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36347341

RESUMO

Flexible switching between different tasks is an important cognitive ability for humans and it is often studied using the task-switching paradigm. Although the neural mechanisms of task switching have been extensively explored in previous studies using event-related potentials techniques, the activity and process mechanisms of non-phase-locked electroencephalography (EEG) have rarely been revealed. For this reason, this paper discusses the processing of non-phase-locked EEG oscillations in task switching based on frequency-band delineation. First, the roles of each frequency band in local brain regions were summarized. In particular, during the proactive control process (the cue-stimulus interval), delta, theta, and alpha oscillations played more roles in the switch condition while beta played more roles in repeat task. In the reactive control process (post-target), delta, alpha, and beta are all related to sensorimotor function. Then, utilizing the functional connectivity (FC) method, delta connections in the frontotemporal regions and theta connections located in the parietal-to-occipital sites are involved in the preparatory period before task switching, while alpha connections located in the sensorimotor areas and beta connections located in the frontal-parietal cortex are involved in response inhibition. Finally, cross-frequency coupling (CFC) play an important role in working memory among different band oscillation. The present study shows that in addition to the processing mechanisms specific to each frequency band, there are some shared and interactive neural mechanism in task switching by using different analysis techniques.


Assuntos
Eletroencefalografia , Potenciais Evocados , Humanos , Potenciais Evocados/fisiologia , Lobo Frontal/fisiologia , Memória de Curto Prazo/fisiologia , Lobo Parietal/fisiologia
10.
Neuropsychologia ; 178: 108443, 2023 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-36481257

RESUMO

The current study examines the extent to which hearing individual-level names (e.g., Jimmy) and category-level labels (e.g., Hitchel) paired with novel objects impacts neural responses across a brief (6 min) learning period. Event-related Potentials (ERPs) were recorded while adult participants (n = 44) viewed and heard exemplars of two different species of named novel objects. ERPs were examined for each labeling condition and compared across the first and second half of the learning trials (∼3 min/half). Mean amplitude decreased for the P1 and increased for the N170 from the first to the second half of trials. The decrease in P1 was right lateralized. In addition, the P1 amplitude recorded over right occipitotemporal regions was greater than left occipitotemporal areas, but only for objects paired with individual-level labels. Category-level labels did not show regional P1 differences. The N250 component was greatest over the right occipitotemporal region and was enhanced for objects labeled with individual-level relative to category-level names during the second half of trials. Overall, these findings highlight the unfolding of label-dependent visual processing across a short training period in adults. The results suggest that linguistic labels have an important, top-down impact, on visual processing and that label specificity shapes visuo-cortical responses within a 6-min learning period.


Assuntos
Eletroencefalografia , Potenciais Evocados , Humanos , Adulto , Potenciais Evocados/fisiologia , Percepção Visual/fisiologia , Aprendizagem/fisiologia
11.
Brain Res ; 1798: 148135, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36332664

RESUMO

Efficient working memory (WM) performance involves the dynamic coordination of neural activity on a millisecond time-scale. However, the correspondence between the timing and spatial localization of changes in neural activity following targeted WM training has not been well-established. To address this, we used an event-related potential (ERP) source localization approach to identify the patterns of cortical activity changes that are induced by WM training along both the temporal and spatial dimensions. Healthy adult participants completed approximately 20 sessions of training on either a WM training protocol (visual-letter n-back task), or a control training protocol (visual-letter search task). ERP measures were obtained before and after training (pretest and posttest) for a letter 3-back task. A beamformer source localization method was applied to the ERP data in the N2 (approximately 200-350 msec post-stimulus) and P3 (approximately 300-600 msec post-stimulus) component time windows to identify the cortical activity associated with WM training at distinct stages of information processing. Pretest-to-posttest cortical activity changes that corresponded with WM training gains were observed within the N2 time window, but not the P3 time window. Within the WM training group, training-related enhancement of N2 source activity in bilateral medial orbitofrontal cortex, left rostral anterior cingulate, and right posterior cingulate cortex was significantly associated with behavioral performance improvements on the trained task and untrained tasks of WM. The findings suggest that medial orbitofrontal and cingulate enhancement within 200-350 msec after stimulus onset represents a target for WM training and an important inflection point along the spatial-temporal dimensions of cortical activity for the enhancement of WM performance.


Assuntos
Aprendizagem , Memória de Curto Prazo , Adulto , Humanos , Potenciais Evocados , Plasticidade Neuronal , Córtex Cerebral
12.
Psychophysiology ; 60(1): e14135, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35775733

RESUMO

Previous studies have revealed the effect of set size (the number of activated items) on object switching in working memory, but the underlying neural mechanism remains unclear. In this study, participants were asked to first remember two (small size) or three (large size) two-digit numbers and the corresponding geometrical figures as different references for numerical comparison and then compare a series of numbers (10-99) to the reference numbers cued by different geometrical figures. The cue repeated or switched across trials. Behavioral results revealed that the switch cost was greater in the large-size condition than in the small-size condition. Event-related potential results showed that in the N2 component, an interaction was observed between set size and transition, with a significant transition effect (switch minus repeat) in the large-size condition and a non-significant transition effect in the small-size condition. The same interaction was observed in the P3 component, with a larger amplitude difference (switch minus repeat) in the large-size condition than in the small-size condition. These results suggested that when set size is increased, the effort to inhibit the irrelevant items increases, resulting in large cost of object switching in working memory.


Assuntos
Potenciais Evocados , Memória de Curto Prazo , Humanos , Memória de Curto Prazo/fisiologia , Potenciais Evocados/fisiologia , Sinais (Psicologia)
13.
Psychophysiology ; 60(1): e14147, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35819753

RESUMO

Previous reports suggest that East-Asians may show larger face-elicited N170 components in the ERP as compared to Caucasian participants. Since the N170 can be modulated by perceptual expertise, such group differences may be accounted for by differential experience, for example, with logographic versus alphabetic scripts (script system hypothesis) or by exposure to abundant novel faces during the immersion into a new social and/or ethnic environment (social immersion hypothesis). We conducted experiments in Hong Kong and Berlin, recording ERPs in a series of one-back tasks, using same- and other-ethnicity face stimuli in upright and inverted orientation and doodle stimuli. In Hong Kong we tested local Chinese residents and foreign guest students who could not read the logographic script; in Berlin we tested German residents who could not read the logographic script and foreign Chinese visitors. In both experiments, we found significantly larger N170 amplitudes to faces, regardless of ethnicity, in the foreign than in the local groups. Moreover, this effect did not depend on stimulus orientation, suggesting that the N170 group differences do not reflect differences in configural visual processing. A group of short-term German residents in Berlin did not differ in N170 amplitude from long-term residents. Together, these findings indicate that the extensive confrontation with novel other-ethnicity faces during immersion in a foreign culture may enhance the neural response to faces, reflecting the short-term plasticity of the underlying neural system.


Assuntos
Eletroencefalografia , Etnicidade , Humanos , Potenciais Evocados/fisiologia , Face
14.
Psychophysiology ; 60(1): e14145, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35834644

RESUMO

Self-positivity bias is a common psychological phenomenon in which individuals often associate positive information with themselves. However, little is known about how self-positivity bias is modulated by different language contexts (e.g., a first vs. second language). To this end, we analyzed behavioral and electrophysiological data to examine whether first or second languages play differential roles in the self-positivity bias effect. We used a modified self-positivity bias task which required Chinese-English bilinguals to judge strings of letters or characters as realwords or not and match associations between identity (self, other) and a geometric shape (circle, triangle). The target words in the experiment consisted of positive, negative, and neutral emotional words. The results showed that in the L2 context, the self-positivity condition elicited a smaller N400 effect relative to the self-negativity condition and a larger late positive component effect relative to the self-negativity and self-neutrality conditions. Furthermore, the other-positivity condition elicited a stronger N400 effect than the other-neutrality condition. These patterns did not emerge in the L1 context. We discuss the implications and contributions of these findings to better understand the interaction between emotion and self-concept in different language contexts.


Assuntos
Potenciais Evocados , Multilinguismo , Humanos , Masculino , Feminino , Potenciais Evocados/fisiologia , Idioma , Eletroencefalografia , Emoções/fisiologia
15.
Psychophysiology ; 60(1): e14153, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35843992

RESUMO

Controversy exists regarding the distraction resistance of priority items in visual working memory (VWM). The protection account proposes that high-priority items resist distraction more than low-priority items, while the vulnerability account proposes that distractors impair high-priority items more. We proposed another available resource threshold account: distraction will not impair items if available resources exceed their threshold needed for sufficient processing. Using a change-detection paradigm, we manipulated item priority by color similarity and inserted distractors during VWM retention. We investigated the effect of similarity on distraction resistance of relevant (color) and irrelevant (shape) feature representations (Experiments 1-2), and the neural mechanism of this effect using event-related potentials (ERPs; Experiment 3). Behavioral results showed distractors impaired the accuracy of dissimilar items when relevant features were memorized and of similar items when irrelevant features were memorized under simultaneous presentation of similar and dissimilar items. Moreover, distractors impaired the accuracy of dissimilar items when relevant features were memorized and of both similar and dissimilar items when irrelevant features were memorized under separate presentation of items. ERP results showed a smaller negative slow wave and P2 but larger N2 under the similar condition. Similarity protected relevant features of similar items against distraction by reducing memory load, decreasing attentional resources allocated to distractors, and strengthening inhibition of distractors. However, similarity did not protect irrelevant features of similar items. Our results support the available resource threshold account, suggesting that VWM is a flexible and intelligent system despite its limited capacity.


Assuntos
Memória de Curto Prazo , Percepção Visual , Humanos , Memória de Curto Prazo/fisiologia , Percepção Visual/fisiologia , Atenção/fisiologia , Potenciais Evocados , Inibição Psicológica
16.
Psychophysiology ; 60(1): e14152, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35867964

RESUMO

Some aspects of our memory are enhanced by emotion, whereas others can be unaffected or even hindered. Previous studies reported impaired associative memory of emotional content, an effect termed associative "emotional interference". The current study used EEG and an associative recognition paradigm to investigate the cognitive and neural mechanisms associated with this effect. In two experiments, participants studied negative and neutral stimulus-pairs that were either semantically related or unrelated. In Experiment 1 emotions were relevant to the encoding task (valence judgment) whereas in Experiment 2 emotions were irrelevant (familiarity judgment). In a subsequent associative recognition test, EEG was recorded while participants discriminated between intact, rearranged, and new pairs. An associative emotional interference effect was observed in both experiments, but was attenuated for semantically related pairs in Experiment 1, where valence was relevant to the task. Moreover, a modulation of an early associative memory ERP component (300-550 ms) occurred for negative pairs when valence was task-relevant (Experiment 1), but for semantically related pairs when valence was irrelevant (Experiment 2). A later ERP component (550-800 ms) showed a more general pattern, and was observed in all experimental conditions. These results suggest that both valence and semantic relations can act as an organizing principle that promotes associative binding. Their ability to contribute to successful retrieval depends on specific task demands.


Assuntos
Potenciais Evocados , Semântica , Humanos , Potenciais Evocados/fisiologia , Eletroencefalografia , Reconhecimento Psicológico/fisiologia , Emoções
17.
Psychophysiology ; 60(1): e14154, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35894226

RESUMO

Both forward and backward working memory span tasks have been used in cognitive training, but no study has been conducted to test whether the two types of trainings are equally effective. Based on data from a randomized controlled trial, this study (N = 60 healthy college students) tested the effects of backward span training, forward span training, and no intervention. Event-related potential (ERP) signals were recorded at the pre-, mid-, and post-tests while the subjects were performing a distractor version of the change detection task, which included three conditions (2 targets and 0 distractor [2T0D]; 4 targets and 0 distractor [4T0D]; and 2 targets and 2 distractors [2T2D]). Behavioral data were collected from two additional tasks: a multi-object version of the change detection task, and a suppress task. Compared to no intervention, both forward and backward span trainings led to significantly greater improvement in working memory maintenance, based on indices from both behavioral (Kmax) and ERP data (CDA_2T0D and CDA_4T0D). Backward span training also improved interference control based on the ERP data (CDA_filtering efficiency) to a greater extent than did forward span training and no intervention, but the three groups did not differ in terms of behavioral indices of interference control. These results have potential implications for optimizing the current cognitive training on working memory.


Assuntos
Potenciais Evocados , Memória de Curto Prazo , Humanos
18.
Psychophysiology ; 60(1): e14160, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35975726

RESUMO

Conflict adaptation is considered to reflect the adjustment of cognitive control, and it is critical for adaptive behavior. Despite intensive investigations on conflict adaptation, straightforward evidence on how changes in conflict strength influence the behavioral and neural dynamics of conflict adaptation remains scarce. To address this issue, we manipulated conflict strength by varying distractor-target congruency to investigate whether conflict strength per se or the expectancy of conflict strength triggers the adjustment of cognitive control. Behavioral and electroencephalographic (EEG) measures were recorded while participants performed a variant four-choice flanker task without feature repetitions. The behavioral results showed that reaction times increased with increasing conflict strength. Importantly, there were conflict adaptations between the congruent and incongruent-low, congruent and incongruent-high, and incongruent-low and incongruent-high conditions. Consistent with the behavioral results, the EEG results revealed that N2 and P3 were sensitive to conflict strength. Critically, there were typical conflict adaptations between every two conflict conditions on the early P3 amplitude related to the adjustment of attentional strategies. However, there were no differences among these conflict adaptation effects, both on reaction times and the early P3 amplitude, demonstrating that the expectancy of conflict strength rather than conflict strength per se may play a crucial role in conflict adaptation. Altogether, these results emphasize the functional role of expectancy based on previous conflict strength in the exertion of cognitive control, which is in accordance with the repetition expectation theory than with the conflict monitoring theory.


Assuntos
Conflito Psicológico , Potenciais Evocados , Humanos , Tempo de Reação , Eletroencefalografia , Atenção , Adaptação Psicológica
19.
Psychophysiology ; 60(1): e14193, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36256483

RESUMO

This review focuses on research my colleagues and I have conducted on etiological pathways to depression. Much of this work has focused on the measurement of neural responses to appetitive cues, using two event-related brain potential (ERP) components, the Late Positive Potential (LPP) and the Reward Positivity (RewP). Reductions in each of these components have been associated with current symptoms of depression, and in some cases have been shown to differentiate anxious from depressive phenotypes. In this review, I will describe three broad and related approaches we have taken in our research to address a series of interdependent issuess. The first attempts to understand different sources of variation in the LPP and RewP, and how these sources interact with one another. The second tries to identify whether variation in the processes measured by these ERP components might reflect a latent vulnerability to depression and its symptoms, that is evident prior to illness onset. And the third examines the possibility that the processes reflected in the LPP and RewP might play a mechanistic role in the development of depression.


Assuntos
Depressão , Eletroencefalografia , Depressão/diagnóstico , Sinais (Psicologia) , Potenciais Evocados/fisiologia , Recompensa
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