1,720,989 research outputs found
Processes of response facilitation and inhibition in the Simon task. A single-pulse transcranial magnetic stimulation (TMS) study
No full textHappy children! A network of psychological and environmental factors associated with the development of positive affect in 9–13 children
Full text link: To deepen the development of positive affect during early adolescence and shed new light on its predictors, this study adopts an exploratory network approach to first identify the main domains that describe the variability of children's psychological, environmental, and behavioral characteristics, and then use these domains to longitudinally predict positive affect and its development within a latent growth framework. To this aim, we considered 10,904 US participants (9 years old at baseline; 13 years old 42 months later), six measurement occasions of positive affect, and 46 baseline indicators from the ABCD study. Our results not only confirm that positive affect declines between 9 and 13 years old, but also show that among the five domains identified (behavioral dysregulation, cognitive functioning, psychological problems, supportive social environment, and extracurricular activities), only a supportive social environment consistently predicts positive affect. This is crucial for practitioners and policymakers, as it can help them focus on the elements within our complex network of psychological, social, and environmental variability
Is cognitive control automatic? New insights from transcranial magnetic stimulation
No full textCognitive control has been classically considered as a flexible process engaged to pursue intentional behaviors, as distinct from automatic processes, which are unintentional, inflexible, and triggered by unconscious mechanisms. Our study challenged this view, showing that such a distinction may not be so clear-cut. We analyzed motor-evoked potentials (MEPs) elicited by transcranial magnetic stimulation to investigate the neurocognitive mechanisms occurring in a conflict task during trials that either required or did not require a response. We observed a Simon effect on MEPs and sequential modulations of such effects on both kinds of trials. Sequential modulations are usually explained as resulting from the engagement of intentional control mechanisms. Our findings rule against this idea, suggesting that these effects are the result of a mechanism that detects and resolves conflict even when there is no intention to select any response. Accordingly, cognitive control also seems to operate without intention, acting in an automatic fashio
Transcranial random noise stimulation (tRNS): a wide range of frequencies is needed for increasing cortical excitability
Full text linkTranscranial random noise stimulation (tRNS) is a recent neuromodulation protocol. The high-frequency band (hf-tRNS) has shown to be the most effective in enhancing neural excitability. The frequency band of hf-tRNS typically spans from 100 to 640 Hz. Here we asked whether both the lower and the higher half of the high-frequency band are needed for increasing neural excitability. Three frequency ranges (100–400 Hz, 400–700 Hz, 100–700 Hz) and Sham conditions were delivered for 10 minutes at an intensity of 1.5 mA over the primary motor cortex (M1). Single-pulse transcranial magnetic stimulation (TMS) was delivered over the same area at baseline, 0, 10, 20, 30, 45 and 60 minutes after stimulation, while motor evoked potentials (MEPs) were recorded to evaluate changes in cortical excitability. Only the full-band condition (100–700 Hz) was able to modulate excitability by enhancing MEPs at 10 and 20 minutes after stimulation: neither the higher nor the lower sub-range of the high-frequency band significantly modulated cortical excitability. These results show that the efficacy of tRNS is strictly related to the width of the selected frequency range
I processi di attivazione corticale alla base dell’effetto Simon e la loro modulazione sequenziale non dipendono dall’esecuzione della risposta: uno studio di stimolazione magnetica transcranica (TMS)
No full textThinking about it: the impact of COVID-19-related stimuli on prospective memory
Full text linkBackground. Since 2020, information regarding COVID-19 has been a constant presence in the news, in our conversations and thoughts. Continuous exposure to this type of stimuli could have an impact on cognitive processes essential for our everyday activities, such as prospective memory (PM). PM is the ability to remember to perform an intention at a specific point in the future, like remembering to take prescribed medicines at a specific time or to turn off the stove after cooking. Do COVID-related stimuli affect our ability to perform a PM task? Methods. To answer this question, we proposed a novel version of the classical paradigm used to investigate PM. Namely, this paradigm includes a baseline condition, in which an ongoing task is presented alone, and a PM condition in which the same task is proposed again together with a second (prospective) task. In this study, a short video clip was presented between the baseline and the PM condition. The video clip displayed either neutral, negative, or COVID-related content. Additionally, participants were asked to respond to two questionnaires and a series of questions regarding their well-being and experience with the pandemic. Namely, the DASS-21 scale (evaluating depression, anxiety, and stress), and the COVID-19-PTSD questionnaire (a questionnaire evaluating post-traumatic stress disorder symptoms related to the pandemic experience) were administered. Participants’ performance and responses were analyzed using a linear mixed effect (LME) model approach, and correlation analyses were run to highlight possible correlations between participants’ scores in the DASS-21, the COVID-19-PTSD, and the additional questions on their personal experience with the pandemic. Results. The LME models revealed significant effects of the displayed video on performance: in line with previous studies, the clip displaying standard negative contents led to impaired accuracy in the ongoing task in the PM condition, compared to the Baseline. In contrast, participants who saw the COVID-related clip showed improved accuracy in the ongoing task compared to the other participants, selectively in the block performed after the video clip was displayed (PM condition). Furthermore, the explanatory power of the LME model calculated on accuracy to the ongoing trials was enhanced by the inclusion of the scores in the anxiety subscale of the DASS-21, suggesting a detrimental role of anxiety. Altogether, these results indicate a different effect of the exposure to classical negative contents (associated with a cost in terms of accuracy in the ongoing task between the baseline and the PM condition) and the pandemic-related one, which was instead characterized by a higher accuracy to ongoing trials compared to the other video clips. This counterintuitive finding seems to suggest that COVID-related stimuli are processed as ``acute stressors'' rather than negative stimuli, thus inducing a state of increased alertness and responsivity
Visual exploration dynamics are low-dimensional and driven by intrinsic factors
Full text linkWhen looking at visual images, the eyes move to the most salient and behaviourally relevant objects. Saliency and semantic information significantly explain where people look. Less is known about the spatiotemporal properties of eye movements (i.e., how people look). We show that three latent variables explain 60% of eye movement dynamics of more than a hundred observers looking at hundreds of different natural images. The first component explaining 30% of variability loads on fixation duration, and it does not relate to image saliency or semantics; it approximates a power-law distribution of gaze steps, an intrinsic dynamic measure, and identifies observers with two viewing styles: static and dynamic. Notably, these viewing styles were also identified when observers look at a blank screen. These results support the importance of endogenous processes such as intrinsic dynamics to explain eye movement spatiotemporal properties
Processi di facilitazione ed inibizione della risposta nel compito Simon. Uno studio di stimolazione magnetica transcranica (TMS)
No full textUnveiling the neural correlates of prospective memory: An ecological EEG study
No full textThe ability to remember intentions for future actions is a fundamental aspect of human functioning in everyday life. This process is typically studied in laboratory settings with tasks designed to isolate it, but these often lack ecological validity because they may not fully capture the complexity and variability of prospective memory (PM) in real-world contexts. The present exploratory study was designed to overcome these limitations. Firstly, participants watched a movie simulating to be home on their sofa. They then continued to watch the movie on their "smart TV", while simultaneously maintaining and executing intentions related to everyday activities, such as "virtual cooking". Neurophysiological activity was recorded during these tasks using an hd-EEG system to investigate the role of brain oscillations in strategic monitoring processes involved in PM. Power spectral density was analyzed across the theta, alpha, and high beta frequency bands. Administration of time-based and eventbased instructions in an ecological context revealed two distinct patterns of brain activity. Time-based PM was characterized by widespread and sustained fronto-temporal activation, along with pronounced engagement of high beta frequencies in prefrontal areas. Event-based PM was associated with theta and alpha power localized to focal areas of the occipito-parietal lobes. According to the PM literature, modulations of theta and alpha oscillations are associated with attentional mechanisms for rehearsing different PM intentions in memory. The involvement of high beta frequencies in the time-based PM condition, already associated with temporal abilities, highlights their role in determining optimal timing for retrieval of future intentions
Sequential modulation of (bottom-up) response activation and inhibition in a response conflict task: a single-pulse transcranial magnetic stimulation study.
No full textMany cognitive tasks involve a response conflict between the response selected on the basis of the task-relevant attribute and that primed by an irrelevant attribute. Although response priming has been extensively investigated, we still have little evidence on whether it entails both excitatory and inhibitory processes and the way in which these processes are modulated by the prior occurrence of a conflict between-response alternatives. To shed light on these issues, we tested motor cortex excitability during a two-choice compatibility task (a Simon task) by delivering single pulses of transcranial magnetic stimulation and recording the resulting motor evoked potentials (MEPs). We obtained consistent behavioural and MEP results suggesting that the presentation of a left- or right-side stimulus causes the activation of the ipsilateral response, which-in turn-inhibits the alternative response. Both processes are modulated by the spatial compatibility of the preceding trial. In trials following compatible trials (i.e. after conditions wherein the primed response was the correct one), we found response efficiency advantages and disadvantages of compatible and incompatible trials, respectively, which were mirrored by an increase of the excitability of the motor cortex primed by stimulus position and by a parallel decrease of the contralateral cortex excitability. Both the facilitation and interference components of the behavioural effect and the excitatory and inhibitory effects of the stimulus position on motor excitability were smaller after neutral trials (i.e. when the stimulus of the previous trial was aligned with fixation, thus not priming any response) and absent after incompatible trials (i.e. after having experienced a conflict between the primed and correct responses). These results are consistent with the idea that location-based response priming is under control of a conflict monitoring mechanism that strengthens ipsilateral response activation and contralateral response inhibition after compatible trials and weakens both processes after incompatible trials
- …
