Response Selection Mechanisms Research Articles

Responsive and Adaptive Designs in Repeated Cross-National Surveys: A Simulation Study

AbstractCross-national surveys run the risk of differential survey errors, where data collected vary in quality from country to country. Responsive and adaptive survey designs (RASDs) have been proposed as a way to reduce survey errors, by leveraging auxiliary variables to inform fieldwork efforts, but have rarely been considered in the context of cross-national surveys. Using data from the European Social Survey, we simulate fieldwork in a repeated cross-national survey using RASD where fieldwork efforts are ended early for selected units in the final stage of data collection. Demographic variables, paradata (interviewer observations), and contact data are used to inform fieldwork efforts. Eight combinations of response propensity models and selection mechanisms are evaluated in terms of sample composition (as measured by the coefficient of variation of response propensities), response rates, number of contact attempts saved, and effects on estimates of target variables in the survey. We find that sample balance can be improved in many country-round combinations. Response rates can be increased marginally and targeting high propensity respondents could lead to significant cost savings associated with making fewer contact attempts. Estimates of target variables are not changed by the case prioritizations used in the simulations, indicating that they do not impact nonresponse bias. We conclude that RASDs should be considered in cross-national surveys, but that more work is needed to identify suitable covariates to inform fieldwork efforts.

Probing the decision-making mechanisms underlying choice between drug and nondrug rewards in rats.

Delineating the decision-making mechanisms underlying choice between drug and nondrug rewards remains a challenge. This study adopts an original approach to probe these mechanisms by comparing response latencies during sampling versus choice trials. While lengthening of latencies during choice is predicted in a deliberative choice model (DCM), the race-like response competition mechanism postulated by the Sequential choice model (SCM) predicts a shortening of latencies during choice compared to sampling. Here, we tested these predictions by conducting a retrospective analysis of cocaine-versus-saccharin choice experiments conducted in our laboratory. We found that rats engage deliberative decision-making mechanisms after limited training, but adopt a SCM-like response selection mechanism after more extended training, while their behavior is presumably habitual. Thus, the DCM and SCM may not be general models of choice, as initially formulated, but could be dynamically engaged to control choice behavior across early and extended training.

Neurophysiological correlates of perception\u2013action binding in the somatosensory system

Action control requires precisely and flexibly linking sensory input and motor output. This is true for both, visuo-motor and somatosensory-motor integration. However, while perception–action integration has been extensively investigated for the visual modality, data on how somatosensory and action-related information is associated are scarce. We use the Theory of Event Coding (TEC) as a framework to investigate perception–action integration in the somatosensory-motor domain. Based on studies examining the neural mechanisms underlying stimulus–response binding in the visuo-motor domain, the current study investigates binding mechanisms in the somatosensory-motor domain using EEG signal decomposition and source localization analyses. The present study clearly demonstrates binding between somatosensory stimulus and response features. Importantly, repetition benefits but no repetition costs are evident in the somatosensory modality, which differs from findings in the visual domain. EEG signal decomposition indicates that response selection mechanisms, rather than stimulus-related processes, account for the behavioral binding effects. This modulation is associated with activation differences in the left superior parietal cortex (BA 7), an important relay of sensorimotor integration.

Differences in unity: The go/no-go and stop signal tasks rely on different mechanisms

Response inhibition refers to the suppression of prepared or initiated actions. Typically, the go/no-go task (GNGT) or the stop signal task (SST) are used interchangeably to capture individual differences in response inhibition. On the one hand, factor analytic and conjunction neuroimaging studies support the association of both tasks with a single inhibition construct. On the other hand, studies that directly compare the two tasks indicate distinct mechanisms, corresponding to action restraint and cancellation in the GNGT and SST, respectively. We addressed these contradictory findings with the aim to identify the core differences in the temporal dynamics of the functional networks that are recruited in both tasks. We extracted the time-courses of sensory, motor, attentional, and cognitive control networks by group independent component (G-ICA) analysis of electroencephalography (EEG) data from both tasks. Additionally, electromyography (EMG) from the responding effector muscles was recorded to detect the timing of response inhibition. The results indicated that inhibitory performance in the GNGT may be comparable to response selection mechanisms, reaching peripheral muscles at around 316 ​ms. In contrast, inhibitory performance in the SST is achieved via biasing of the sensorimotor system in preparation for stopping, followed by fast sensory, motor and frontal integration during outright stopping. Inhibition can be detected at the peripheral level at 140 ​ms after stop stimulus presentation. The GNGT and the SST therefore seem to recruit widely different neural dynamics, implying that the interchangeable use of superficially similar inhibition tasks in both basic and clinical research is unwarranted.

Categorical Biases in Human Occipitoparietal Cortex.

Categorization allows organisms to generalize existing knowledge to novel stimuli and to discriminate between physically similar yet conceptually different stimuli. Humans, nonhuman primates, and rodents can readily learn arbitrary categories defined by low-level visual features, and learning distorts perceptual sensitivity for category-defining features such that differences between physically similar yet categorically distinct exemplars are enhanced, whereas differences between equally similar but categorically identical stimuli are reduced. We report a possible basis for these distortions in human occipitoparietal cortex. In three experiments, we used an inverted encoding model to recover population-level representations of stimuli from multivoxel and multielectrode patterns of human brain activity while human participants (both sexes) classified continuous stimulus sets into discrete groups. In each experiment, reconstructed representations of to-be-categorized stimuli were systematically biased toward the center of the appropriate category. These biases were largest for exemplars near a category boundary, predicted participants' overt category judgments, emerged shortly after stimulus onset, and could not be explained by mechanisms of response selection or motor preparation. Collectively, our findings suggest that category learning can influence processing at the earliest stages of cortical visual processing.SIGNIFICANCE STATEMENT Category learning enhances perceptual sensitivity for physically similar yet categorically different stimuli. We report a possible mechanism for these changes in human occipitoparietal cortex. In three experiments, we used an inverted encoding model to recover population-level representations of stimuli from multivariate patterns in occipitoparietal cortex while participants categorized sets of continuous stimuli into discrete groups. The recovered representations were systematically biased by category membership, with larger biases for exemplars adjacent to a category boundary. These results suggest that mechanisms of categorization shape information processing at the earliest stages of the visual system.

Intact Motivation in Major Depression: Normative Responsiveness to Action-Effectiveness Demonstrated in a Clinical Sample

Ultimately, motivation enables survival through goal-directed behaviour and is evident through the direction and force of action. While a plethora of candidate responses are generated by the brain, response-selection mechanisms are responsible for evaluating and selecting the most adaptive course of action given the current context. Although motivation is known to be modulated by tangible rewards (such as food or monetary gain), substantial evidence has accumulated to suggest that both the direction and speed of responding can be modulated by feedback indicating mere influence over the environment or 'pure effectiveness' (e.g., Hemed et al., in press; Wen et al., 2018). In general, clinically depressed individuals are characterized as being less-motivated and less-active, both motorically and mentally (Sobin & Sackeim, 1997). The current study examines whether people diagnosed with Major Depressive Disorder (MDD) are similarly sensitive to (and are motivated by) effectiveness-feedback as healthy individuals are. Clinically depressed participants (N=75) performed a task in which their responses either led to action-effects or did not (i.e. effectiveness-feedback). The results show that effectiveness-feedback motivated individuals suffering from MDD, at least as strong as previously established in healthy individuals. These results suggest that the motivational system is fully activated by relevant effectiveness-feedback in MDD and imply that the motivational deficit in this condition is either limited to an outcome or goal-relevant feedback or other desired-outcome related processes. A more radical conclusion would be that a motivational deficit per-se is not a defining feature of this condition.

The impact of stimulus modality on the processing of conflicting sensory information during response inhibition

Response inhibition is a central aspect of cognitive control. Usually, response inhibition is examined using information from a single sensory modality. Yet, evidence suggests that conflicts between information from different modalities affect response inhibition. It is, however, crucial to consider that there are modality differences in the efficiency to trigger response inhibition that may also modulate the impact of conflicts between different sensory modalities. In the current study, we compared an auditory–tactile to an auditory–visual Go/NO-GO task. We recorded EEG data and performed signal decomposition and source localization. On the behavioral level, we show stronger interference effects in the visual than the tactile modality. Despite sensory processes were experimentally varied, temporally decomposed EEG data show that response selection mechanisms are associated with these effects and not the sensory processing stage. These modulations of response selection processes occur in the temporo-parietal junction (TPJ, BA40) and inferior frontal structures (IFG, BA47). The smaller activity in the TPJ during auditory–tactile, compared to auditory–visual conflicts suggests that task representations are less affected by interfering auditory information when the tactile modality informs response inhibition processes. This also explains why less intense braking processes (reflected by IFG activity) are still able to maintain a reasonable response inhibition performance level. It can be concluded that the tactile and visual domains do not only differ in regard to their efficiency to trigger response inhibition processes but also in their susceptibility to interference while informing inhibitory control. Clinical implications are discussed.

Multi-factor analysis in language production: Sequential sampling models mimic and extend regression results

ABSTRACTFor multi-factor analyses of response times, descriptive models (e.g., linear regression) arguably constitute the dominant approach in psycholinguistics. In contrast empirical cognitive models (e.g., sequential sampling models, SSMs) may fit fewer factors simultaneously, but decompose the data into several dependent variables (a multivariate result), offering more information to analyze. While SSMs are notably popular in the behavioural sciences, they are not significantly developed in language production research. To contribute to the development of this modelling in language, we (i) examine SSMs as a measurement modelling approach for spoken word activation dynamics, and (ii) formally compare SSMs to the default method, regression. SSMs model response activation or selection mechanisms in time, and calculate how they are affected by conditions, persons, and items. While regression procedures also model condition effects, it is only in respect to the mean RT, and little work has been previously done to compare these approaches. Through analyses of two language production experiments, we show that SSMs reproduce regression predictors, and further extend these effects through a multivariate decomposition (cognitive parameters). We also examine a combined regression-SSM approach that is hierarchical Bayesian, which can jointly model more conditions than classic SSMs, and importantly, achieve by-item modelling with other conditions. In this analysis, we found that spoken words principally differed from one another by their activation rates and production times, but not their thresholds to be activated.

Paradoxical response inhibition advantages in adolescent obsessive compulsive disorder result from the interplay of automatic and controlled processes.

Response inhibition deficits have often been described in obsessive compulsive disorder (OCD). Yet, research on response inhibition in OCD focusses on “top-down” controlled mechanisms, and it has been neglected that response inhibition performance depends on the interplay of controlled and automatic processes during response selection. Based on pathophysiological considerations we test the counterintuitive hypothesis that OCD patients show superior inhibitory control when automatic mechanisms govern processes involved in response inhibition. We examined a group of adolescent OCD patients (n = 27) and healthy controls (n = 27) using a combined Simon-Go/NoGo task. This task is able to examine conjoint effects of automatic and controlled processes during response inhibition. EEG and source localization analyses were applied to examine the underlying neural mechanisms. OCD patients committed fewer false alarms than healthy controls (HC) in the congruent Simon-NoGo condition, which is dominated by automatic response selection mechanisms. On a neurophysiological (EEG) level, these effects were reflected by intensified correlates of ‘braking’ processes associated with modulation of right inferior prefrontal regions. There is no general response inhibition deficit in adolescent OCD. When considering conjoint effects of automatic and controlled processes during the inhibition of responses paradoxical response inhibition advantages can emerge in OCD. This is likely a result of otherwise pathological fronto-striatal hyperactivity and loss of a situation-specific modulation of response selection mechanisms in OCD.

The neurophysiological basis of developmental changes during sequential cognitive flexibility between adolescents and adults.

Cognitive flexibility is a major facet of executive functions and often refers to sequential task control; that is, it is very likely that one may re-encounter a task that has previously been abandoned to carry out a different task. In the context of sequential cognitive flexibility, the "backward inhibition (BI) effect" has been studied quite extensively. Here we ask whether there are age-related differences between adolescents and adults to overcome BI and what system-neurophysiological mechanisms underlie these modulations. This was examined using a system neurophysiological study procedure combining event-related potentials data with source localization and EEG signal decomposition methods. We show that sequential cognitive flexibility, and the ability overcome backward inhibition, is inferior in adolescents compared with adults. Accounting for intra-individual variability in the neurophysiological data, this data suggest that two partly inter-related processes underlie the differences between adolescents than adults to overcome backward inhibition: One process refers to the suppression of the inhibitory effect of the n-1 trial on the n-2 trial during perceptual categorization of incoming information that is associated with right inferior frontal regions. The other process refers to immature response selection and conflict monitoring mechanisms associated with regions in the medial frontal cortex.

Effects of multisensory stimuli on inhibitory control in adolescent ADHD: It is the content of information that matters.

Even though deficits in inhibitory control and conflict monitoring are well-known in ADHD, factors that further modulate these functions remain to be elucidated. One factor that may be of considerable importance is how inhibitory control is modulated by multisensory information processing. We examined the influence of concurrent auditory conflicting or redundant information on visually triggered response inhibition processes in adolescent ADHD patients and healthy controls. We combined high-density event-related potential (ERP) recordings with source localization to delineate the functional neuroanatomical basis of the involved neurophysiological processes. In comparison to controls, response inhibition (RI) processes in ADHD were compromised in conflicting conditions, but showed no differences to controls when redundant or no concurrent auditory information was presented. These effects were reflected by modulations at the response selection stage (P3 ERP) in the medial frontal gyrus (BA32), but not at the attentional selection (P1, N1 ERPs) or resource allocation level (P2 ERP). Conflicting information during RI exerts its influences in adolescent ADHD via response selection mechanisms, but not via attentional selection. It is not the mere presence of concurrent information, but the presence of conflicting information during RI that may destabilize goal shielding processes in medial frontal cortical regions, by means of increasing the automaticity of response tendencies. The occurring RI deficits might relate to the increased impulsivity in adolescent ADHD and a corresponding vulnerability to react to an increased automaticity of pre-potent response tendencies. ADHD patients show a bias to a specific content of information which can modulate inhibitory control.

Neural mechanisms underlying successful and deficient multi-component behavior in early adolescent ADHD.

Attention Deficit Hyperactivity Disorder (ADHD) is a disorder affecting cognitive control. These functions are important to achieve goals when different actions need to be executed in close succession. This type of multi-component behavior, which often further requires the processing of information from different modalities, is important for everyday activities. Yet, possible changes in neurophysiological mechanisms have not been investigated in adolescent ADHD. We examined N = 31 adolescent ADHD patients and N = 35 healthy controls (HC) in two Stop-Change experiments using either uni-modal or bi-modal stimuli to trigger stop and change processes. These stimuli were either presented together (SCD0) or in close succession of 300 milliseconds (SCD300). Using event-related potentials (ERP), EEG data decomposition and source localization we analyzed neural processes and functional neuroanatomical correlates of multicomponent behavior. Compared to HCs, ADHD patients had longer reaction times and higher error rates when Stop and Change stimuli were presented in close succession (SCD300), but not when presented together (SCD0). This effect was evident in the uni-modal and bi-modal experiment and is reflected by neurophysiological processes reflecting response selection mechanisms in the inferior parietal cortex (BA40). These processes were only detectable after accounting for intra-individual variability in neurophysiological data; i.e. there were no effects in standard ERPs. Multi-component behavior is not always deficient in ADHD. Rather, modulations in multi-component behavior depend on a critical temporal integration window during response selection which is associated with functioning of the inferior parietal cortex. This window is smaller than in HCs and independent of the complexity of sensory input.

The Basal Ganglia Striosomes Affect the Modulation of Conflicts by Subliminal Information—Evidence from X-Linked Dystonia Parkinsonism

Cognitive control is relevant when distracting information induces behavioral conflicts. Such conflicts can be produced consciously and by subliminally processed information. Interestingly, both sources of conflict interact suggesting that they share neural mechanisms. Here, we ask whether conjoint effects between different sources of conflict are modulated by microstructural basal ganglia dysfunction. To this end, we carried out an electroencephalography study and examined event-related potentials (ERPs) including source localization using a combined flanker-subliminal priming task in patients with X-linked dystonia Parkinsonism (XDP) and a group of healthy controls. XDP in its early stages is known to predominantly affect the basal ganglia striosomes. The results suggest that conjoint effects between subliminal and conscious sources of conflicts are modulated by the striosomes and were stronger in XDP patients. The neurophysiological data indicate that this effect is related to modulations in conflict monitoring and response selection (N2 ERP) mechanisms engaging the anterior cingulate cortex. Bottom-up perceptual gating, attentional selection, and motor response activation processes in response to the stimuli (P1, N1, and lateralized readiness potential ERPs) were unaffected. Taken together, these data indicate that striosomes modulate the processing of conscious and subliminal sources of conflict suggesting that microstructural basal ganglia properties are relevant for cognitive control.

The role of dimension relevance in features' access to response-selection mechanisms.

It is widely agreed that attending to a stimulus entails that all its features are processed. However, whether all these features are granted access to response-selection mechanisms remains a debated issue. Some authors suggest that all the features of the attended object affect response selection, irrespective of their relevance to the task at hand, whereas others claim that only its currently relevant features do. Yet others suggest that irrelevant features of an attended object affect response selection only if this object is the target, that is, only if it is selected for action. The results from 3 experiments show that responses associated with an attended object's irrelevant dimension interfered with response selection even when this object was not selected for action, but to a lesser extent than the responses associated with its relevant dimension. Our findings also show that interference from the irrelevant dimension can be masked when the response codes associated with the relevant and irrelevant dimensions compete. We suggest a parsimonious account of the findings from the extant literature that obviates the need to postulate a qualitative distinction between attention and selection for action. (PsycINFO Database Record

Functional connectivity correlates of response inhibition impairment in anorexia nervosa

Anorexia nervosa (AN) is a disorder characterized by high levels of cognitive control and behavioral perseveration. The present study aims at exploring inhibitory control abilities and their functional connectivity correlates in patients with AN. Inhibitory control – an executive function that allows the realization of adaptive behavior according to environmental contingencies – has been assessed by means of the Stop-Signal paradigm. The study involved 155 patients with lifetime AN and 102 healthy women. A subsample underwent resting-state functional magnetic resonance imaging and was genotyped for COMT and 5-HTTLPR polymorphisms. AN patients showed an impaired response inhibition and a disruption of the functional connectivity of the ventral attention circuit, a neural network implicated in behavioral response when a stimulus occurs unexpected. The 5-HTTLPR genotype appears to significantly interact with the functional connectivity of ventral attention network in explaining task performance in both patients and controls, suggesting a role of the serotoninergic system in mechanisms of response selection. The disruption of the ventral attention network in patients with AN suggests lower efficiency of bottom-up signal filtering, which might be involved in difficulties to adapt behavioral responses to environmental needs. Our findings deserve further research to confirm their scientific and therapeutic implications.

Competitive interactions in sensorimotor cortex: oscillations express separation between alternative movement targets.

Choice behavior is influenced by factors such as reward and number of alternatives but also by physical context, for instance, the relative position of alternative movement targets. At small separation, speeded eye or hand movements are more likely to land between targets (spatial averaging) than at larger separation. Neurocomputational models explain such behavior in terms of cortical activity being preshaped by the movement environment. Here, we manipulate target separation, as a determinant of motor cortical activity in choice behavior, to address neural mechanisms of response selection. Specifically, we investigate whether context-induced changes in the balance of cooperative and competitive interactions between competing groups of neurons are expressed in the power spectrum of sensorimotor rhythms. We recorded magnetoencephalography while participants were precued to two possible movement target locations at different angles of separation (30, 60, or 90°). After a delay, one of the locations was cued as the target for a joystick pointing movement. We found that late delay-period movement-preparatory activity increased more strongly for alternative targets at 30 than at 60 or 90° of separation. This nonlinear pattern was evident in slow event-related fields as well as in beta- and low-gamma-band suppression. A comparable pattern was found within an earlier window for theta-band synchronization. We interpret the late delay effects in terms of increased movement-preparatory activity when there is greater overlap and hence less competition between groups of neurons encoding two response alternatives. Early delay-period theta-band synchronization may reflect covert response activation relevant to behavioral spatial averaging effects.

Asymmetrical switch costs in bilingual language production induced by reading words.

We examined language-switching effects in French-English bilinguals using a paradigm where pictures are always named in the same language (either French or English) within a block of trials, and on each trial, the picture is preceded by a printed word from the same language or from the other language. Participants had to either make a language decision on the word or categorize it as an animal name or not. Picture-naming latencies in French (Language 1 [L1]) were slower when pictures were preceded by an English word than by a French word, independently of the task performed on the word. There were no language-switching effects when pictures were named in English (L2). This pattern replicates asymmetrical switch costs found with the cued picture-naming paradigm and shows that the asymmetrical pattern can be obtained (a) in the absence of artificial (nonlinguistic) language cues, (b) when the switch involves a shift from comprehension in 1 language to production in another, and (c) when the naming language is blocked (univalent response). We concluded that language switch costs in bilinguals cannot be reduced to effects driven by task control or response-selection mechanisms.

ARITO: Cyber-attack response system using accurate risk impact tolerance

We propose a novel approach for automated intrusion response systems to assess the value of the loss that could be suffered by a compromised resource. A risk assessment component of the approach measures the risk impact and is tightly integrated with our response system component. When the total risk impact exceeds a certain threshold, the response selection mechanism applies one or more responses. A multi-level response selection mechanism is proposed to gauge the intrusion damage (attack progress) relative to the response impact. This model proposes a feedback mechanism, which measures the response goodness and helps indicate the new risk level following application of the response(s). Not only does our proposed model constitutes a novel online mechanism for response activation and deactivation based on the online risk impact, it also addresses the factors inherent in assessing risk and calculating response effectiveness that are more complex in terms of detail. We have designed a sophisticated multi-step attack to penetrate Web servers, as well as to acquire root privilege. Our simulation results illustrate the efficiency of the proposed model and confirm the feasibility of the approach in real time. At the end of paper, we discuss the various ways in which an attacker might succeed in completely bypassing our response system.

Effects of Working Memory Demand on Neural Mechanisms of Motor Response Selection and Control

Inhibitory control commonly recruits a number of frontal regions: pre-supplementary motor area (pre-SMA), frontal eye fields (FEFs), and right-lateralized posterior inferior frontal gyrus (IFG), dorsal anterior insula (DAI), dorsolateral prefrontal cortex (DLPFC), and inferior frontal junction (IFJ). These regions may directly implement inhibitory motor control or may be more generally involved in executive control functions. Two go/no-go tasks were used to distinguish regions specifically recruited for inhibition from those that additionally show increased activity with working memory demand. The pre-SMA and IFG were recruited for inhibition in both tasks and did not have greater activation for working memory demand on no-go trials, consistent with a role in inhibitory control. Activation in pre-SMA also responded to response selection demand and was increased with working memory on go trials specifically. The bilateral FEF and right DAI were commonly active for no-go trials. The FEF was also recruited to a greater degree with working memory demand on go trials and may bias top-down information when stimulus-response mappings change. The DAI, additionally responded to increased working memory demand on both go and no-go trials and may be involved in accessing sustained task information, alerting, or autonomic changes when cognitive demands increase. DLPFC activation was consistent with a role in working memory retrieval on both go and no-go trials. The inferior frontal junction, on the other hand, had greater activation with working memory specifically for no-go trials and may detect salient stimuli when the task requires frequent updating of working memory representations.

The functional tumor necrosis factor-α (308A/G) polymorphism modulates attentional selection in elderly individuals

There has been increasing interest in understanding the role of inflammatory processes for cognitive functions in aging using molecular genetic approaches. Though this has mostly been evaluated in pathological aging, little is known about the relevance for cognitive functions in healthy aging in humans. On the basis of behavioral data and neurophysiological data (event-related potentials and time–frequency decomposition) we show that the A-allele of the functional tumor necrosis factor (TNF)-α -308 A/G polymorphism confers dysfunction in a number of cognitive processes: prolonged attentional selection indexed by a delayed P1/N1 complex, an increased P3a, which is interpreted as an enhanced distractibility by nonrelevant stimuli and compromised response selection mechanisms, as indexed by a reduced frontocentral N2. Time–frequency analyses show that allelic variations further exert their effects by modulating alpha and beta frequency oscillations. On a neurobiological level, these effects might be because of the interaction of TNF-α with glutamatergic neural transmission by which TNF-α is known to boost apoptotic mechanisms in elderly individuals.