Incongruent Items Research Articles

Sorting the News: How Ranking by Popularity Polarizes Our Politics

ABSTRACTMost people receive political news from social media platforms. Unlike traditional media, these platforms algorithmically determine the order in which news is presented, in part relying on an article’s popularity (i.e. number of likes, shares, and comments) to determine its ranking. To what extent does sorting the news by popularity influence people’s attitudes toward politics? With two large, nationally representative samples of adults and a novel experimental design, we find that ranking news articles by their popularity has consequential effects that vary depending on the partisan composition of the group upon which the rankings are based. Overall, algorithmic sorting exacerbates the tendency to “like” news that conform to the dominant viewpoint of the reference group. For example, when the group is ideologically like-minded, the in-party bias in “liking” creates a self-perpetuating cycle, where attitudinally congruent articles remain at the top of the feed. When the reference group is rather composed of out-party members, politically incongruent items rise to the top. While this helps to expose readers to new information, they also become disengaged from reading and sharing political news. Overall, our study holds important implications for how using social media as an outlet for political information can influence – and even polarize – our political preferences.

Inhibiting the Whole Number Bias in a Fraction Comparison Task: An Event-Related Potential Study.

IntroductionPeople often use heuristics derived from natural number tasks to solve fraction comparison tasks. For instance, one may falsely consider a fraction with a larger natural number to be the larger in magnitude, as in the case of 1/5 vs 1/4. We hypothesized that inhibitory control was needed to overcome this type of bias.MethodsTo test the hypothesis, Event-related potentials (ERP) were collected when participants were conducting fraction comparison tasks that designed with the negative priming paradigm. Twenty-eight adult participants performed three types of fraction comparison tasks: congruent items, incongruent items and neutral items.ResultsWe found a negative priming effect in terms of response time. Consistently, ERP results demonstrated larger N1 and N2 amplitudes and a smaller P3 amplitude in the test trial than in the control trial.ConclusionThese findings indicated that adults still need to inhibit the “larger natural number-larger fraction” misleading strategy when solving fraction comparison tasks with common components.

Bold moves: Inevitable saccadic selection in visual short-term memory.

Selection for visual short-term memory (vstm) provides a basis for many cognitive functions. Saccadic eye movements sway this selection in favor of stimuli previously seen at locations congruent with their target. In three experiments, we provide converging evidence that this saccadic selection is implemented as a fundamental, inevitable selection process, rather than a top-down strategy. In particular, benefits for congruent over incongruent items were largely constant across set sizes ranging from two to eight items (Experiment 1), showing that saccadic selection imposes priorities on vstm irrespective of memory load and is effective even when only few representations need to be maintained. Moreover, a decrement in performance for incongruent items occurred reliably, whether the congruent location contained a task-relevant item or an irrelevant noise patch (Experiment 2). Finally, saccadic selection was immune to a strong manipulation of the observer's attentional priorities (Experiment 3). Given the prevalence of saccades in natural vision, our results demonstrate a fundamental and ecologically relevant selection mechanism for vstm: Saccades systematically eliminate information seen at non-target locations, while information at the saccade target remains available to recall. This simple heuristic is effective in the absence of informative cues and may incapacitate voluntary selection mechanisms that are incongruent with ongoing movement plans.

Consistently inconsistent: Multimodal episodic deficits in semantic aphasia

Semantic Aphasia (SA) patients have difficulty accessing semantic knowledge in both verbal and non-verbal tasks appropriately for the current context. Automatically activated semantic knowledge overwhelms the system, because it is no longer able to inhibit interference from dominant meanings in order to select weaker alternatives. Episodic memory, like semantic memory, requires control to select relevant memories amongst competing episodes. For example, our memory for what we ate for breakfast last Saturday is affected by competition from numerous other breakfast meals eaten on other days. Where one is unable to guide retrieval, we may rely on automatically activated knowledge about “breakfast foods”, and therefore experience false memories. Brain systems that support semantic control are also implicated in episodic control, and therefore deficits in semantic control are likely to cause more widespread problems. Despite this, nearly all research to date focuses on semantic performance alone. This study explored the impact of this semantic impairment on episodic recall. We used a verbal and non-verbal episodic memory task: participants remembered nursery rhymes in the verbal condition and logos and their associated products in the visual condition (e.g. bowl of cereal and coco-pops). For both tasks, we manipulated a) congruency with pre-existing knowledge (e.g. expectancy of trials: baa baa blackbuild – instead of sheep) and b) whether these trial types were blocked by congruency or mixed, as well as (c) distractor strength. If SA patients experience overwhelming automatic activation, they should find incongruent items more difficult to suppress, particularly when presented in an unpredictable task format. A total of 13 SA patients were compared to 33 controls across three experiments. In line with our predictions, SA patients found it more difficult to retrieve episodic memories which were in conflict with pre-existing semantic knowledge. This was true across modalities. Moreover, these deficits were accentuated when the congruency was presented in a mixed fashion, and so unpredictable across trials. Evidence of these episodic control impairments in SA cases supports the idea of a shared mechanism for semantic and episodic memory control.

Multimodal processing in simultaneous interpreting with text

Abstract The present study focuses on (in)congruence of input between the visual and the auditory modality in simultaneous interpreting with text. We asked twenty-four professional conference interpreters to simultaneously interpret an aurally and visually presented text with controlled incongruences in three categories (numbers, names and control words), while measuring interpreting accuracy and eye movements. The results provide evidence for the dominance of the visual modality, which goes against the professional standard of following the auditory modality in the case of incongruence. Numbers enjoyed the greatest accuracy across conditions possibly due to simple cross-language semantic mappings. We found no evidence for a facilitation effect for congruent items, and identified an impeding effect of the presence of the visual text for incongruent items. These results might be interpreted either as evidence for the Colavita effect (in which visual stimuli take precedence over auditory ones) or as strategic behaviour applied by professional interpreters to avoid risk.

Selective attention effects on recognition: the roles of list context and perceptual difficulty.

Two recent studies reported superior recognition memory for items that were incongruent targets than for items that were congruent targets in a prior incidental study phase (Krebs et al. in Cereb Cortex (New York, NY) 25(3):833-843, 2015; Rosner et al. in Psychol Res 79(3):411-424, 2015). The present study examined this effect further by addressing two issues. First, we examined whether this effect is sensitive to the list context in which congruent and incongruent items are presented. In Experiment 1, this issue was addressed by manipulating the relative proportions of congruent and incongruent trials in the study phase. In Experiments 2A and 2B, the same issue was examined by contrasting randomly intermixed and blocked manipulations of congruency. The results of these experiments, as well as a trial-to-trial sequence analysis, demonstrate that the recognition advantage for incongruent over congruent items is robust and remarkably insensitive to list context. Second, we examined recognition of incongruent and congruent items relative to a single word baseline condition. Incongruent (Experiment 3A) and congruent (Experiment 3B) items were both better recognized than single word items, though this effect was substantially stronger for incongruent items. These results suggest that perceptual processing difficulty, rather than interference caused by different target and distractor identities on its own, contributes to the enhanced recognition of incongruent items. Together, the results demonstrate that processes that are sensitive to perceptual processing difficulty of items but largely insensitive to list context produce heightened recognition sensitivity for incongruent targets.

Some do and some don't? Accounting for variability of individual difference structures.

A prevailing notion in experimental psychology is that individuals' performance in a task varies gradually in a continuous fashion. In a Stroop task, for example, the true average effect may be 50 ms with a standard deviation of say 30 ms. In this case, some individuals will have greater effects than 50 ms, some will have smaller, and some are forecasted to have negative effects in sign-they respond faster to incongruent items than to congruent ones! But are there people who have a true negative effect in Stroop or any other task? We highlight three qualitatively different effects: negative effects, null effects, and positive effects. The main goal of this paper is to develop models that allow researchers to explore whether all three are present in a task: Do all individuals show a positive effect? Are there individuals with truly no effect? Are there any individuals with negative effects? We develop a family of Bayesian hierarchical models that capture a variety of these constraints. We apply this approach to Stroop interference experiments and a near-liminal priming experiment where the prime may be below and above threshold for different people. We show that most tasks people are quite alike-for example everyone has positive Stroop effects and nobody fails to Stroop or Stroops negatively. We also show a case that under very specific circumstances, we could entice some people to not Stroop at all.

Dynamic Causal Modeling of Preclinical Autosomal-Dominant Alzheimer's Disease.

Dynamic causal modeling (DCM) is a framework for making inferences about changes in brain connectivity using neuroimaging data. We fitted DCMs to high-density EEG data from subjects performing a semantic picture matching task. The subjects are carriers of the PSEN1 mutation, which leads to early onset Alzheimer’s disease, but at the time of EEG acquisition in 1999, these subjects were cognitively unimpaired. We asked 1) what is the optimal model architecture for explaining the event-related potentials in this population, 2) which connections are different between this Presymptomatic Carrier (PreC) group and a Non-Carrier (NonC) group performing the same task, and 3) which network connections are predictive of subsequent Mini-Mental State Exam (MMSE) trajectories. We found 1) a model with hierarchical rather than lateral connections between hemispheres to be optimal, 2) that a pathway from right inferotemporal cortex (IT) to left medial temporal lobe (MTL) was preferentially activated by incongruent items for subjects in the PreC group but not the NonC group, and 3) that increased effective connectivity among left MTL, right IT, and right MTL was predictive of subsequent MMSE scores.

Beneficial and detrimental effects of schema incongruence on memory for contextual events.

Mental schemas provide a framework into which new information can easily be integrated. In a series of experiments, we examined how incongruence that stems from a prediction error modulates memory for multicomponent events that instantiated preexisting schemas as noted in a previous study. Each event consisted of four stimulus pairs with overlapping components, presented in four blocks (A–B, B–C, C–D, D–A). A–B pairs elicited contextual expectations (A: Farm, B: Tractor) that were either met by a congruent C component (C: Farmer) or violated by an incongruent one (C: Lawyer). The baseline condition included unrelated pairs, where the C component was neither congruent nor incongruent. In experiment 2, events were presented in successive trials instead of blocks, and eye movements were recorded to analyze allocation of attention. Memory was tested through old–new item recognition followed by cued recall. Across experiments, recognition and recall performance for incongruent components was reduced compared to congruent components. Incongruent items were in some cases more accurately retrieved compared to unrelated ones, depending on task demands. Additionally, better recall was observed in the incongruent D–A pairs, compared to congruent and unrelated ones, because of reduced interference from C components. Eye-tracking revealed an increased number of fixations on C components in the incongruent and unrelated conditions. These results suggest that the integration of incongruent items into an episode is impaired, compared to congruent items, despite the contextual surprise and increased attention they elicited at encoding. However, there was a beneficial effect of prediction error on memory performance, compared to a baseline, depending on the task used.

Measuring connection and collaboration in rehabilitation: Developing a measure of therapeutic relationship

The therapeutic relationship may be critical to rehabilitation outcome. However, knowledge advance is hampered by existing measures, which were not designed for use in the rehabilitation context and fail to capture essential elements. Drawing on a conceptual framework developed through prior research, we aimed to develop a robust measure of therapeutic relationship, tailored to the rehabilitation context. A measure development study drawing on steps proposed by Prior et al., 2011. We undertook a literature search to identify existing measures of therapeutic relationship. All items were extracted and mapped against our conceptual framework. We removed duplicate and conceptually incongruent items, and developed new items for aspects not already captured. We reworded items to ensure consistency in item scoring direction and language. A preliminary pool of 68 items were then piloted with rehabilitation clients using cognitive interviewing methods to determine their comprehensibility, acceptability, relevance and answerability. The research team met to examine the data and identified items for deletion or revision. Clients ( n = 13) were drawn from a diversity of contexts and included people with neurological ( n = 5), long-term chronic ( n = 4), and acute ( n = 4) conditions. We deleted 32 and reworded eight items in response to feedback. Reasons for deletion included overlap with other items ( n = 22), not relevant across populations/context ( n = 5), ambiguous ( n = 4), or too global ( n = 1). A 36-item scale was derived aiming to measure therapeutic relationship in rehabilitation. This measure is now being pilot tested with a larger cohort of clients to further refine the measure using Rasch analysis.

Possibility of semantic involvement in the L1-L2 congruency effect in the processing of L2 collocations

Abstract A growing body of second language (L2) research has identified the congruency effect in the processing of L2 collocations (L2 collocations that have word-for-word translation equivalents in learners’ first language [L1] are processed more quickly and accurately than those that have no such forms in L1). However, the locus of this effect has yet to be fully understood. This study explored the possibility of semantic involvement in this phenomenon by categorizing congruent and incongruent items used in the past studies according to the semantic transparency of collocations. Results showed a clear dominance of transparent items in the congruent category and that of opaque items in the incongruent category, suggesting the possibility of semantic involvement in the congruency effect. However, considerations of other factors observed in the pertinent studies led to the conclusion that there is something more in the congruency effect beyond semantic transparency.

Eye movements reveal persistent sensitivity to sound symbolism during word learning.

Although the relationship between sound and meaning in language is assumed to be largely arbitrary, reliable correspondences between sound and meaning in natural language appear to facilitate word learning. Using a set of independently normed pseudoword and shape stimuli, we examined the real-time effects of sound-to-shape correspondences at initial presentation and throughout an extended learning process resulting in high accuracy. In addition to accuracy and response time (RT) measures, we monitored participants' eye movements to investigate the extent to which visual orienting to objects is influenced by the sound symbolic characteristics of novel labels at initial exposure and throughout learning. Over the course of word learning, congruency of sound and shape properties affected both accuracy and RT with higher accuracy and faster responses for congruent than incongruent items. Eye tracking data reveal that congruent targets were fixated faster than incongruent targets throughout learning and that nontargets consistent with the sound symbolic properties of the word remained attractive distracters, even after overt behavioral differences in accuracy disappeared. This demonstrates the sustained influence of sound symbolism and the importance of sensitive, continuous measures of assessing sound symbolic effects in word learning and lexical processing. Arbitrariness resulted in better final individuation performance only when the arbitrary items were more phonologically distinct than the sound symbolic stimuli. These findings suggest that the advantages of sound symbolism may persist beyond early word learning and serve to significantly influence online lexical processing. (PsycINFO Database Record

Beyond the face: how context modulates emotion processing in frontotemporal dementia subtypes.

The importance of assessing social cognition to characterize dementia syndromes is increasingly recognized, with lower social cognition capacity associated with reduced functional independence and greater carer burden. Emotion recognition is impaired in both behavioural-variant frontotemporal dementia and semantic dementia, yet the social and behavioural changes observed in these syndromes in everyday situations varies. To date, most studies have investigated isolated, context-free stimuli indexing recognition of facial emotions only. Here, we aimed to investigate how contextual information (i.e. emotional body language) influences emotion recognition, within the framework of the Social Context Network Model. Thirty-one patients with frontotemporal dementia (19 behavioural-variant frontotemporal dementia; 12 semantic dementia) and 20 healthy age- and education-matched controls were assessed on three tasks which varied contextual cues: (i) face alone; (ii) context alone; and (iii) face embedded in context. Voxel-based morphometry was used to identify neural correlates of task performance. Our results demonstrated that both behavioural-variant frontotemporal dementia and semantic dementia patients performed worse than controls in recognizing emotions from face alone and context alone. Importantly, performance differed when faces were presented in context. While both behavioural-variant frontotemporal dementia and semantic dementia patients performed similarly to controls on congruent items (i.e. face emotion and body emotion are the same) (P-values > 0.05), patients with behavioural-variant frontotemporal dementia performed worse than both controls (P < 0.001) and patients with semantic dementia (P = 0.044) for incongruent items (i.e. face emotion and body emotion are different). Neuroimaging analyses revealed that abnormal contextual influence was associated with lower integrity of the right parahippocampal gyrus/amygdala and left precentral gyrus. Together, these results indicate that patients with behavioural-variant frontotemporal dementia are over-reliant on external contextual information. Conversely, in semantic dementia and controls, contextual influence varies, with the degree of contextual influence appearing to be mediated, at least in part, by the facial expression depicted. The profile in behavioural-variant frontotemporal dementia is reminiscent of the 'environmental dependency syndrome' described in frontal lesion patients. It also converges with recent evidence of abnormal face perception in this group. From a theoretical perspective, our findings demonstrate that the capacity to incorporate contextual body language is dependent on the integrity of both contextual association brain regions (i.e. parahippocampal gyrus), as well as regions necessary for processing dynamic body movements. Clinically, these results open new avenues for rehabilitation of social impairments in dementia.

The effect of dopaminergic medication on conflict adaptation in Parkinson's disease.

Parkinson's disease (PD) is a neurological disorder associated primarily with motor symptoms such as tremor, slowness of movement, and difficulties with gait and balance. Most patients take dopaminergic medication to improve their motor functions. Previous studies reported indications that such medication can impair higher cognitive functions (cf. dopamine overdose hypothesis). In the present study, we examined the effect of medication status on conflict adaptation. PD patients performed a Stroop task in which we manipulated the proportion of congruent and incongruent items, thereby allowing us to explore conflict adaptation. The use of mouse movements allowed us to examine the action dynamics of conflict adaptation in PD, and their sensitivity to dopaminergic medication. Each patient performed the same task twice: once without making changes to their regular medication regime, and once after overnight withdrawal from their medication. Results showed that medication improved mouse movements and alleviated motor symptoms. Moreover, patients' mouse movements were modulated as a function of the proportion congruency manipulation, revealing conflict adaptation in PD, which was unaffected by medication status. The present study extends earlier work on conflict adaptation in PD where reduced transient (trial-by-trial) conflict adaptation was observed ON compared to OFF medication (Duthoo etal., 2013, Neuropsychology, 27, 556). Our findings suggest that more sustained cognitive control processes may not be sensitive to dopamine overdose effects.

Can color changes alter the neural correlates of recognition memory? Manipulation of processing affects an electrophysiological indicator of conceptual implicit memory.

It has been widely shown that recognition memory includes two distinct retrieval processes: familiarity and recollection. Many studies have shown that recognition memory can be facilitated when there is a perceptual match between the studied and the tested items. Most event-related potential studies have explored the perceptual match effect on familiarity on the basis of the hypothesis that the specific event-related potential component associated with familiarity is the FN400 (300-500 ms mid-frontal effect). However, it is currently unclear whether the FN400 indexes familiarity or conceptual implicit memory. In addition, on the basis of the findings of a previous study, the so-called perceptual manipulations in previous studies may also involve some conceptual alterations. Therefore, we sought to determine the influence of perceptual manipulation by color changes on recognition memory when the perceptual or the conceptual processes were emphasized. Specifically, different instructions (perceptually or conceptually oriented) were provided to the participants. The results showed that color changes may significantly affect overall recognition memory behaviorally and that congruent items were recognized with a higher accuracy rate than incongruent items in both tasks, but no corresponding neural changes were found. Despite the evident familiarity shown in the two tasks (the behavioral performance of recognition memory was much higher than at the chance level), the FN400 effect was found in conceptually oriented tasks, but not perceptually oriented tasks. It is thus highly interesting that the FN400 effect was not induced, although color manipulation of recognition memory was behaviorally shown, as seen in previous studies. Our findings of the FN400 effect for the conceptual but not perceptual condition support the explanation that the FN400 effect indexes conceptual implicit memory.

Measuring attitudes towards suicide: Preliminary evaluation of an attitude towards suicide scale

ObjectivesOur study aimed to validate a previously published scale assessing attitudes towards suicide. Factor structure, convergent and discriminant validity, and predictive validity were investigated. MethodAdult German participants (N=503; mean age=24.74years; age range=18–67years) anonymously completed a set of questionnaires. An exploratory factor analysis was conducted, and incongruous items were deleted. Subsequently, scale properties of the reduced scale and its construct validity were analyzed. A confirmatory factor analysis was then conducted in an independent sample (N=266; mean age=28.77years; age range=18–88years) to further confirm the factor structure of the questionnaire. ResultsParallel analysis indicated a three-factor solution, which was also supported by confirmatory factor analysis: right to commit suicide, interpersonal gesture and resilience. The subscales demonstrated acceptable construct and discriminant validity. Cronbach's α for the subscales ranged from 0.67 to 0.83, explaining 49.70% of the total variance. ConclusionsPositive attitudes towards suicide proved to be predictive of suicide risk status, providing preliminary evidence for the utility of the scale. Future studies aiming to reproduce the factor structure in a more heterogeneous sample are warranted.

Early Stages of Sensory Processing, but Not Semantic Integration, Are Altered in Dyslexic Adults.

The aim of this study was to verify which stages of language processing are impaired in individuals with dyslexia. For this, a visual-auditory crossmodal task with semantic judgment was used. The P100 potentials were chosen, related to visual processing and initial integration, and N400 potentials related to semantic processing. Based on visual-auditory crossmodal studies, it is understood that dyslexic individuals present impairments in the integration of these two types of tasks and impairments in processing spoken and musical auditory information. The present study sought to investigate and compare the performance of 32 adult participants (14 individuals with dyslexia), in semantic processing tasks in two situations with auditory stimuli: sentences and music, with integrated visual stimuli (pictures). From the analysis of the accuracy, both the sentence and the music blocks showed significant effects on the congruency variable, with both groups having higher scores for the incongruent items than for the congruent ones. Furthermore, there was also a group effect when the priming was music, with the dyslexic group showing an inferior performance to the control group, demonstrating greater impairments in processing when the priming was music. Regarding the reaction time variable, a group effect in music and sentence priming was found, with the dyslexic group being slower than the control group. The N400 and P100 components were analyzed. In items with judgment and music priming, a group effect was observed for the amplitude of the P100, with higher means produced by individuals with dyslexia, corroborating the literature that individuals with dyslexia have difficulties in early information processing. A congruency effect was observed in the items with music priming, with greater P100 amplitudes found in incongruous situations. Analyses of the N400 component showed the congruency effect for amplitude in both types of priming, with the mean amplitude for incongruent items being greater than that of the congruent items. Electrophysiological findings were corroborated by the N400 literature and showed that the semantic processing of individuals with dyslexia was preserved. Furthermore, the findings indicate P100 visual sensory processing deficits in the dyslexic group and may suggest difficulty in the sensory stimuli process.

Disentangling Genuine Semantic Stroop Effects in Reading from Contingency Effects: On the Need for Two Neutral Baselines.

The automaticity of reading is often explored through the Stroop effect, whereby color-naming is affected by color words. Color associates (e.g., “sky”) also produce a Stroop effect, suggesting that automatic reading occurs through to the level of semantics, even when reading sub-lexically (e.g., the pseudohomophone “skigh”). However, several previous experiments have confounded congruency with contingency learning, whereby faster responding occurs for more frequent stimuli. Contingency effects reflect a higher frequency-pairing of the word with a font color in the congruent condition than in the incongruent condition due to the limited set of congruent pairings. To determine the extent to which the Stroop effect can be attributed to contingency learning of font colors paired with lexical (word-level) and sub-lexical (phonetically decoded) letter strings, as well as assess facilitation and interference relative to contingency effects, we developed two neutral baselines: each one matched on pair-frequency for congruent and incongruent color words. In Experiments 1 and 3, color words (e.g., “blue”) and their pseudohomophones (e.g., “bloo”) produced significant facilitation and interference relative to neutral baselines, regardless of whether the onset (i.e., first phoneme) was matched to the color words. Color associates (e.g., “ocean”) and their pseudohomophones (e.g., “oshin”), however, showed no significant facilitation or interference relative to onset matched neutral baselines (Experiment 2). When onsets were unmatched, color associate words produced consistent facilitation on RT (e.g., “ocean” vs. “dozen”), but pseudohomophones (e.g., “oshin” vs. “duhzen”) failed to produce facilitation or interference. Our findings suggest that the Stroop effects for color and associated stimuli are sensitive to the type of neutral baseline used, as well as stimulus type (word vs. pseudohomophone). In general, contingency learning plays a large role when repeating congruent items more than incongruent items, but appropriate pair-frequency matched neutral baselines allow for the assessment of genuine facilitation and interference. Using such baselines, we found reading processes proceed to a semantic level for familiar words, but not pseudohomophones (i.e., phonetic decoding). Such assessment is critical for separating the effects of genuine congruency from contingency during automatic word reading in the Stroop task, and when used with color associates, isolates the semantic contribution.

Sleep deprivation selectively disrupts top-down adaptation to cognitive conflict in the Stroop test.

Sleep deprivation is known to exert detrimental effects on various cognitive domains, including attention, vigilance and working memory. Seemingly at odds with these findings, prior studies repeatedly failed to evidence an impact of prior sleep deprivation on cognitive interference in the Stroop test, a hallmark paradigm in the study of cognitive control abilities. The present study investigated further the effect of sleep deprivation on cognitive control using an adapted version of the Stroop test that allows to segregate top-down (attentional reconfiguration on incongruent items) and bottom-up (facilitated processing after repetitions in responses and/or features of stimuli) components of performance. Participants underwent a regular night of sleep or a night of total sleep deprivation before cognitive testing. Results disclosed that sleep deprivation selectively impairs top-down adaptation mechanisms: cognitive control no longer increased upon detection of response conflict at the preceding trial. In parallel, bottom-up abilities were found unaffected by sleep deprivation: beneficial effects of stimulus and response repetitions persisted. Changes in vigilance states due to sleep deprivation selectively impact on cognitive control in the Stroop test by affecting top-down, but not bottom-up, mechanisms that guide adaptive behaviours.

Generalizing attentional control across dimensions and tasks: evidence from transfer of proportion-congruent effects.

Three experiments investigated transfer of list-wide proportion congruent (LWPC) effects from a set of congruent and incongruent items with different frequency (inducer task) to a set of congruent and incongruent items with equal frequency (diagnostic task). Experiments 1 and 2 mixed items from horizontal and vertical Simon tasks. Tasks always involved different stimuli that varied on the same dimension (colour) in Experiment 1 and on different dimensions (colour, shape) in Experiment 2. Experiment 3 mixed trials from a manual Simon task with trials from a vocal Stroop task, with colour being the relevant stimulus in both tasks. There were two major results. First, we observed transfer of LWPC effects in Experiments 1 and 3, when tasks shared the relevant dimension, but not in Experiment 2. Second, sequential modulations of congruency effects transferred in Experiment 1 only. Hence, the different transfer patterns suggest that LWPC effects and sequential modulations arise from different mechanisms. Moreover, the observation of transfer supports an account of LWPC effects in terms of list-wide cognitive control, while being at odds with accounts in terms of stimulus-response (contingency) learning and item-specific control.