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Cognitive flexibility (CF) has been proposed as a potential trait marker in anorexia nervosa (AN), although findings have been inconsistent. To address this inconsistency, we applied a model that distinguishes between three subtypes of CF: task switching, switching sets, and stimulus-response mapping, which we then assessed using a paradigm-based task battery. The aim of the study was to investigate how AN is associated with these three CF subtypes. Thirty-three women with AN and 37 age- and education-matched controls performed a battery of computerized cognitive tasks to assess the three CF subtypes. Compared to the control group, individuals with AN exhibited poorer performance on the task switching and switching sets subtypes, as measured by response time switch cost, but not on the stimulus-response mapping subtype. No differences were found between the groups in response accuracy. Furthermore, switching sets as compared to the task switching and stimulus-response mapping subtypes was found to better explain the differences between the groups. These findings indicate a domain-specific impairment in CF among patients with AN, reflecting deficits observed in subtypes related to the disorder's characteristics, particularly that associated with visual perception. Therefore, CF impairment in AN should not be viewed dichotomously, but rather as a relative impairment that varies depending on the specific CF subtype.

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Research findings on cognitive flexibility (CF) functioning in women who recovered from anorexia nervosa (RAN) were found to be inconsistent. This was attributed to the multiple definitions of CF and the diverse measuring tools used to assess it. Applying a deductive approach to explore CF function may address these inconsistencies; thus, we used a model that divides CF into three subtypes, namely, stimulus-response mapping, switching sets and task switching. Additionally, we explored the association between CF subtypes and the disorder's clinical measures to assess the relation of CF to recovery. Forty-three RAN and 54 healthy controls performed tasks designed to assess CF subtypes based on the model's division, and the RAN group completed the Eating Disorder Examination Questionnaire. The results showed that the RAN group performed significantly worse than controls only in the stimulus-response mapping subtype. Additionally, there were no correlations between CF subtypes and clinical symptoms or the disorder measures - current and nadir body mass index, age of onset, time since recovery, and disorder duration. In conclusion, the study revealed CF impairment after recovery from AN, specifically in stimulus-response mapping. The variability in performance of the CF subtypes supports the application of a theory-driven perspective viewing CF as a modular ability in RAN. Additionally, CF is unrelated to clinical measures post-recovery and thus may not be used as a criterion for evaluating recovery.

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Despite the prevalence of visuomotor transformations in our motor skills, their mechanisms remain incompletely understood, especially when imagery actions are considered such as mentally picking up a cup or pressing a button. Here, we used a stimulus-response task to directly compare the visuomotor transformation underlying overt and imagined button presses. Electroencephalographic activity was recorded while participants responded to highlights of the target button while ignoring the second, non-target button. Movement-related potentials (MRPs) and event-related desynchronization occurred for both overt movements and motor imagery (MI), with responses present even for non-target stimuli. Consistent with the activity accumulation model where visual stimuli are evaluated and transformed into the eventual motor response, the timing of MRPs matched the response time on individual trials. Activity-accumulation patterns were observed for MI, as well. Yet, unlike overt movements, MI-related MRPs were not lateralized, which appears to be a neural marker for the distinction between generating a mental image and transforming it into an overt action. Top-down response strategies governing this hemispheric specificity should be accounted for in future research on MI, including basic studies and medical practice.

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There has been an increasing interest in uncovering the mechanisms underpinning how people decide which task to perform at a given time. Many studies suggest that task representations are crucial in guiding such voluntary task selection behavior, which is primarily reflected in a bias to select task repetitions over task switches. However, it is not yet clear whether the task-specific motor effectors are also a crucial component of task representations when deciding to switch tasks. Across three experiments using different voluntary task switching (VTS) procedures, we show that a greater overlap in task representations with a task-to-finger mapping than task-to-hand mapping increases participants' switching behavior (Exp. 1 and Exp. 2), but not when they were instructed to randomly select tasks (Exp. 3). Thus, task-specific stimulus-response associations can change the way people mentally represent tasks and influence switching behavior, suggesting that motor effectors should be considered as a component of task representations in biasing cognitive flexibility.

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Task-switching cost is highly reliable in old participants. However, in a Stroop-switching paradigm that compared old musicians with old non-musicians (Experiment 1A), task-switching costs were not consistent. For non-musicians, the task-switching costs were significant in the congruent and neutral trials, but not in the incongruent trials. For musicians, the task-switching costs disappeared completely. We suspected that besides following task rules, old participants might also apply a stimulus-based strategy called the target-first strategy. In Experiment 1B and 2, participants in Experiment 1A were invited again to perform two more Stroop-switching paradigms. To encourage the participants to use task rules, in Experiment 1B we removed the neutral trials but found the same results as in Experiment 1A. In Experiment 2, when inserting a cue-target interval in the Stroop-switching paradigm, both musicians and non-musicians produced reliable task-switching costs in all trial conditions. Note that younger participants had reliable task-switching costs in Experiment 1B and 2. We suggest that older participants preferred the target-first strategy to the task rules-based strategy because the former was easy to implant although it was less flexible. Besides task-switching costs, we found that old musicians had less interference effect than old non-musicians in Experiment 1B. In all three experiments, old musicians had shorter RTs than old non-musicians, which might be due to differences in strategies apart from cognitive abilities. We propose that without considering the strategy preference, some previous studies might misestimate the difference between old and young participants in terms of task-switching performance and interference control.

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The study examined effects of spatial stimulus-response compatibility on response time and response accuracy in 20 novice combat sport athletes. Two equivalent groups, based on initial reaction time measures, were required to perceive and move quickly and accurately in response to an unspecific visual stimulus presented on a large screen during the two types of perceptual training in eight laboratory sessions. One group reacted by moving the fist toward the stimulus location on the target (direct compatibility condition). Another group was required to move the fist away from target in the opposite direction (indirect compatibility condition). Specifically, the indirect compatibility group achieved faster reaction times than the direct compatibility group during the two posttests containing video-projected attacks of the opponents, and in one of the two posttests containing real opponents' attacks. Results seem to reveal higher combat performance against real opponents when athletes trained with an indirect stimulus-response compatibility condition.

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The implicit acquisition of complex probabilistic regularities has been found to be crucial in numerous automatized cognitive abilities, including language processing and associative learning. However, it has not been completely elucidated how the implicit extraction of second-order nonadjacent transitional probabilities is reflected by neurophysiological processes. Therefore, this study investigated the sensitivity of event-related brain potentials (ERPs) to these probabilistic regularities embedded in a sequence of visual stimuli without providing explicit information on the structure of the stimulus stream. Healthy young adults (N = 32) performed a four-choice RT task that included a sequential regularity between nonadjacent trials yielding a complex transitional probability structure. ERPs were measured relative to both stimulus and response onset. RTs indicated the rapid acquisition of the sequential regularity and the transitional probabilities. The acquisition process was also tracked by the stimulus-locked and response-locked P3 component: The P3 peak was larger for the sequence than for the random stimuli, while the late P3 was larger for less probable than for more probable short-range relations among the random stimuli. According to the RT and P3 effects, sensitivity to the sequential regularity is assumed to be supported by the initial sensitivity to the transitional probabilities. These results suggest that stimulus-response contingencies on the probabilistic regularities of the ongoing stimulus context are implicitly mapped and constantly revised. Overall, this study (1) highlights the role of predictive processes during implicit memory formation, and (2) delineates a potential to gain further insight into the dynamics of implicit acquisition processes.

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In the human visual system, different attributes of an object are processed separately and are thought to be then temporarily bound by attention into an integrated representation to produce a specific response. However, if such representations existed in the brain for arbitrary multi-attribute objects, a combinatorial explosion problem would be unavoidable. Here, we show that attention may bind features of different attributes only in pairs and that bound feature pairs, rather than integrated object representations, are associated with responses for unfamiliar objects. We found that in a mapping task from three-attribute stimuli to responses, presenting three attributes in pairs (two attributes in each window) did not significantly complicate feature integration and response selection when the stimuli were not very familiar. We also found that repeated presentation of the same triple conjunctions significantly improved performance on the stimulus-response task when the correct responses were determined by the combination of three attributes, but this familiarity effect was not observed when the response could be determined by two attributes. These findings indicate that integration of three or more attributes is a distinct process from that of two, requiring long-term learning or some serial process. This suggests that integrated object representations are not formed or are formed only for a limited number of very familiar objects, which resolves the computational difficulty of the binding problem.

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Receptive field (RF) models are an important tool for deciphering neural responses to sensory stimuli. The two currently popular RF models are multifilter linear-nonlinear (LN) models and context models. Models are, however, never correct, and they rely on assumptions to keep them simple enough to be interpretable. As a consequence, different models describe different stimulus-response mappings, which may or may not be good approximations of real neural behavior. In the current study, we take up two tasks: 1) we introduce new ways to estimate context models with realistic nonlinearities, that is, with logistic and exponential functions, and 2) we evaluate context models and multifilter LN models in terms of how well they describe recorded data from complex cells in cat primary visual cortex. Our results, based on single-spike information and correlation coefficients, indicate that context models outperform corresponding multifilter LN models of equal complexity (measured in terms of number of parameters), with the best increase in performance being achieved by the novel context models. Consequently, our results suggest that the multifilter LN-model framework is suboptimal for describing the behavior of complex cells: the context-model framework is clearly superior while still providing interpretable quantizations of neural behavior. NEW & NOTEWORTHY We used data from complex cells in primary visual cortex to estimate a wide variety of receptive field models from two frameworks that have previously not been compared with each other. The models included traditionally used multifilter linear-nonlinear models and novel variants of context models. Using mutual information and correlation coefficients as performance measures, we showed that context models are superior for describing complex cells and that the novel context models performed the best.

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Models of the spatial-numerical association of response codes (SNARC) effect-faster responses to small numbers using left effectors, and the converse for large numbers-diverge substantially in localizing the root cause of this effect along the numbers' processing chain. One class of models ascribes the cause of the SNARC effect to the inherently spatial nature of the semantic representation of numerical magnitude. A different class of models ascribes the effect's cause to the processing dynamics taking place during response selection. To disentangle these opposing views, we devised a paradigm combining magnitude comparison and stimulus-response switching in order to monitor modulations of the SNARC effect while concurrently tapping both semantic and response-related processing stages. We observed that the SNARC effect varied nonlinearly as a function of both manipulated factors, a result that can hardly be reconciled with a unitary cause of the SNARC effect.

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Video games have become both a widespread leisure activity and a substantial field of research. In a variety of tasks, video game players (VGPs) perform better than non-video game players (NVGPs). This difference is most likely explained by an alteration of the basic mechanisms underlying visuospatial attention. More specifically, the present study hypothesizes that VGPs are able to shift attention faster than NVGPs. Such alterations in attention cannot be disentangled from changes in stimulus-response mappings in reaction time based measurements. Therefore, we used a spatial cueing task with varying cue lead times (CLTs) to investigate the speed of covert attention shifts of 98 male participants divided into 36 NVGPs and 62 VGPs based on their weekly gaming time. VGPs exhibited higher peak and mean performance than NVGPs. However, we did not find any differences in the speed of covert attention shifts as measured by the CLT needed to achieve peak performance. Thus, our results clearly rule out faster stimulus-response mappings as an explanation for the higher performance of VGPs in line with previous studies. More importantly, our data do not support the notion of faster attention shifts in VGPs as another possible explanation.

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Attentional selection of sensory information and motor output is critical for successful interaction with one's surroundings. However, organization of attentional processes involved in selection of salient visual information, decision making, and movement planning has not yet been fully elucidated. We hypothesized that attentional processes involved in these tasks can function independently and draw from separate resources. If true, challenging the capacity limit of one attentional process would not affect performance of others. Healthy participants performed a cued saccade task in which target cues were embedded in a central stream of letters in a Rapid Serial Visual Presentation (RSVP). Participants performed saccades as quickly and as accurately as possible to a peripheral target location based on cue presentation within the central letter stream. To challenge visual attention, we parametrically varied the duration at which each letter of the RSVP was presented (50-200ms). In a separate experiment we challenged motor attention by increasing the number of possible saccade trajectories (1-6 peripheral targets). As expected, increasing attentional load in one domain of the task negatively affected performance in that domain, while performance in other domains was unaffected. We interpret our results as support for the independent allocation of attentional resources, at least in the early stages of processing, required across components of a cued saccade task. Deciphering the contributions of attention during visuomotor tasks is a critical step to understanding how humans process information necessary to successfully interact with the environment.

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