Cue-type manipulation dissociates two types of task set inhibition: backward inhibition and competitor rule suppression

Backward inhibition (BI) reflects the suppression of a recently abandoned task set to allow for smooth transition to a new task even when the rules do not generate a response conflict. Competitor rule suppression (CRS) reflects the inhibition/suppression of irrelevant task rules when these rules generate a response conflict even if they have not recently been abandoned. We assessed whether BI and CRS are differentially affected by the difficulty in retrieving category-response mappings from memory. Retrieval demands were manipulated via the information provided by the task cues, which either indicated the relevant dimension (dimension cues; “color”) or the relevant dimension with its category-to-key mapping (mapping cues; “red green”, indicating that “red” and “green” go with the left/right responses, respectively). CRS was larger with dimension compared to mapping cues when cue-type varied between groups and was larger after trials involving dimension cues when cue-type varied on a trial-by-trial basis. In contrast, BI was not influenced by cue-type. These results suggest that task switching involve at least two distinct inhibitory processes, with CRS being related to the ease of retrieval of category-response mappings from memory.     

Sustained attention is related to heartbeat counting task performance but not to self-reported aspects of interoception and mindfulness

Although association between sustained attention and various aspects of interoception (i.e. the perception of the body state) seems plausible, research on this subject is scarce. In the present study, 74 undergraduate students (41 females; age: 22.3 ± 4.04 yrs) filled out the Body Awareness Questionnaire, the Mindful Attention Awareness Scale, and the Somatosensory Amplification Scale and completed the Heartbeat Counting Task (HCT), a sensory-perceptual measure of cardiac interoception and the PEBL Continuous Performance Test (CPT) assessing sustained attention. The HCT score showed a weak to moderate negative correlation with the number of commission errors shown in CPT, indicating a lack of response inhibition (frequentist analysis: r_s = −0.313, p = 0.008; Bayesian analysis: τ_b = −0.216, BF₁₀ = 5.865). Questionnaire measures did not show any connection with CPT-performance. These findings suggest that the subjective representation of attentiveness to bodily processes is unrelated to the objectively measured sustained attention. Response inhibition, however, is moderately related to HCT performance.     

Psychopathy is related to negative affectivity but not to anxiety sensitivity

Although the hypothesis that psychopathic individuals are characterized by a reduced capacity for experiencing anxiety is central to many theories of psychopathy, most prior studies have examined anxiety and fear measures generally considered outdated in the literature. Moreover, prior findings are mixed, with several studies reporting no relationships between psychopathy and anxiety, and others suggesting negative relationships for the affective, interpersonal aspects of the disorder and positive relationships for the antisocial behavior dimension. To examine whether psychopathy dimensions are associated with contemporary measures of anxiety, the Anxiety Sensitivity Index and State Trait Anxiety Inventory-Trait scale were administered to 157 male inmates. Participants also completed the MMPI-derived Welsh Anxiety Scale (WAS), commonly used in psychopathy studies. Analyses provide no evidence for a negative relationship between psychopathy's affective, interpersonal factor and anxiety sensitivity after controlling for trait anxiety. Trait anxiety and WAS scores were positively associated with the antisocial behavior dimension of psychopathy. Findings do replicate prior relationships between the WAS and psychopathy, suggesting the WAS may measure aspects of negative affectivity that differ from anxiety.     

Inhibition of object identity in inhibition of return: Implications for encoding and retrieving inhibitory processes

Inhibition of return (IOR) effects, in which participants detect a target in a cued box more slowly than one in an uncued box, suggest that behavior is aided by inhibition of recently attended irrelevant locations. To investigate the controversial question of whether inhibition can be applied to object identity in these tasks, in the present research we presented faces upright or inverted during cue and/or target sequences. IOR was greater when both cue and target faces were upright than when cue and/or target faces were inverted. Because the only difference between the conditions was the ease of facial recognition, this result indicates that inhibition was applied to object identity. Interestingly, inhibition of object identity affected IOR both whenencoding a cue face andretrieving information about a target face. Accordingly, we propose that episodic retrieval of inhibition associated with object identity may mediate behavior in cuing tasks.     

Trait aggression is related to anger-modulated deficits in response inhibition

The goal of the present study was to investigate the role of emotion-modulated response inhibition in individual difference in the disposition towards aggressive behavior (i.e. trait aggression). One hundred and twelve undergraduate participants completed a behavioral measure of emotion modulated response inhibition (an emotional go/no-go task), self-report measures previously shown to predict aggression (Big-5 traits, impulsivity), and the Aggression Questionnaire (AQ) as a measure of trait aggression. Results show that deficient inhibition to angry, but not happy, faces were related to trait aggression but not to other traits. These findings provide support for the role of specific top down executive control mechanisms in the regulation of aggressive tendencies and highlight the importance of examining these mechanisms in an emotional context.     

2D:4D in men is related to aggressive dominance but not to sociable dominance

It has been shown that a smaller ratio between the length of the second and fourth digit (2D:4D) is an indicator of the exposure to prenatal testosterone (T). This study measured the 2D:4D of men and assessed dominance as a personality trait to investigate indirectly if the exposure to prenatal T is related to a dominant personality later in life. Results showed that men had a more aggressive dominant personality when having a more masculine (lower) 2D:4D, while there was no relationship between sociable dominance and 2D:4D. Findings from this study indicate that it is important to distinguish different forms of dominance since other studies failed to find relationships between dominance and 2D:4D.     

Refining the understanding of inhibitory processes: how response prepotency is created and overcome

Understanding (a) how responses become prepotent provides insights into when inhibition is needed in everyday life. Understanding (b) how response prepotency is overcome provides insights for helping children develop strategies for overcoming such tendencies. Concerning (a), on tasks such as the day‐night Stroop‐like task, is the difficulty with inhibiting saying the name of the stimulus due to the name being semantically related to the correct response or to its being a valid response on the task (i.e. a member of the response set) though incorrect for this stimulus? Experiment 1 (with 40 4‐year‐olds) suggests that prepotency is caused by membership in the response set and not semantic relation. Concerning (b), Diamond, Kirkham and Amso (2002) found that 4‐year‐olds could succeed on the day‐night task if the experimenter sang a ditty after showing the stimulus card, before the child was to respond. They concluded that it was because delaying children’s responses gave them time to compute the correct answer. However, Experiment 2 (with 90 3‐year‐olds) suggests that such a delay helps because it gives the incorrect, prepotent response time to passively dissipate, not because of active computation during the delay.     

Lower begging responsiveness of host versus parasitic brown-headed cowbird (Molothrus ater) nestlings is related to species identity but not to early social experience

The survival of young brood parasites depends critically on their many adaptations to exploit hosts. Parasitic survival is particularly related to competitive superiorty for foster parental care whenever host young are not destroyed in parasitized nests.Brown-headed cowbirds (Molothrus ater) are generalist obligate parasites whose early social environments are unpredictable regarding host species and numbers of nestmates. Young avian brood parasites typically beg more intensively and loudly than foster siblings, but an untested prediction is that young parasites are also more likely to respond by begging to a wider variety of stimulus types. Avian vocalizations were used in a playback experiment to stimulate begging behavior in cowbird hosts. Compared with age-matched cowbird nestlings, hosts begged less frequently to acoustic stimuli, and lower begging responsiveness was irrespective of whether hosts had been reared in parasitized nests.     

Dispositional pessimism but not optimism is related to sickness absence caused by musculoskeletal symptoms

Musculoskeletal disorders account for a higher proportion of sickness absence from work in the European Union than any other health condition. The present study examined the associations between work environment, dispositional optimism/pessimism and medically certified sickness absence caused by musculoskeletal complaints in a sample of employees from the Norwegian Armed Forces (N = 1190, 77.5% men). Dispositional pessimism, but not optimism, predicted the amount of absence also when taking into account the effects of age and the work environment. Overall, our results support previous studies suggesting that pessimism is a more salient predictor of physical health than optimism. Our results also suggest that it may be beneficial for employers to combine medical treatment of musculoskeletal symptoms with psychological treatment targeting pessimistic outcome expectancies in order to reduce the amount of sickness absence.     

H-reflex excitability is inhibited in soleus,but not gastrocnemius,at the short-latency response of a horizontal jump-landing task

Impaired spinal-level neuromuscular control is suggested to contribute to instability and injury during dynamic landing tasks. Despite this suggestion, spinal-level neuromuscular control is yet to be examined during a horizontal jump-landing task. The aim of the current study was to assess changes in H-reflexes and its reliability at the short-latency response of landings from short and long distances. Eight healthy individuals (five male, three female; age, 22 ± 1.2 yrs; height, 178 ± 8.1 cm; weight, 72 ± 15.7 kg) participated in the study. H-reflexes were evoked at the SLR in the soleus and medial gastrocnemius muscles, during two landing conditions: 25% and 50% of maximal broad jump distance. H-reflexes were expressed relative to the background electromyography (EMG) and maximal M-wave responses (M-max). Soleus H-reflexes were inhibited when landing from shorter distance (25%, 13.9 ± 7.6%; 50%, 8.3 ± 6.5%; p < 0.01). No change in H-reflex excitability was observed in medial gastrocnemius. Background EMG was unaltered across landing conditions. Inhibition of soleus H-reflex excitability from 25% to 50% landing condition indicates a reduced contribution of Ia-afferent feedback to the alpha-motor neuron during landings from greater distances, which may contribute to stiffness regulation at the ankle joint. Unaltered H-reflex excitability of medial gastrocnemius is most likely attributed to its functional role during the landing task.     

Dog is a dog is a dog: infant rule learning is not specific to language

Human infants possess powerful learning mechanisms used for the acquisition of language. To what extent are these mechanisms domain specific? One well-known infant language learning mechanism is the ability to detect and generalize rule-like similarity patterns, such as ABA or ABB [Marcus, G. F., Vijayan, S., Rao, S. B., & Vishton, P. M. (1999). Rule learning by seven-month-old infants. Science, 283, 77-80.]. The results of three experiments demonstrate that 7-month-old infants can detect and generalize these same patterns when the elements consist of pictures of animals (dogs and cats). These findings indicate that rule learning of this type is not specific to language acquisition.     

Newborn right-holding is related to depressive symptoms in bottle-feeding mothers but not in breastfeeding mothers

This study examines the relationships between infant holding preferences and maternal depression according to the newborn feeding mode. Links between depression and infant holding biases have been observed in mothers [Vauclair, J., Scola, C. (in press). Dépression, alexithymie et latéralisation dans la fa?on de porter un nouveau-né [Infant holding biases in relation to depression, alexithymia and laterality]. Annales Médico-psychologiques; Weatherill, R. P., Almerigi, J. B., Levendosky, A. A., Bogat, G. A., von Eye, A., & Harris, L. J. (2004). Is maternal depression related to side of infant holding? International Journal of Behavioral Development, 28, 421-427] but the fact that breastfeeding has never been studied in relation to these two factors is surprising as breastfeeding has some influence on depression (e.g., [Mezzacappa, E. S., Guethlein, W., Vaz, N., & Bagiella, E. (2000). A preliminary study of breast-feeding and maternal symptomatology. Annals of Behavioral Medicine, 22, 71-79]) and must also affect holding biases. Mothers who just gave birth (N=100) were tested few days after delivery. Measures of handedness, infant holding-side preferences, and level of depressive symptoms expressed by mothers (assessed with the CES-D scale) were collected via questionnaires. Asymmetries in emotional perception were assessed via a Chimeric Figure Task and a Dichotic Listening Task. Results showed that breastfeeding (1) reduced left-side bias for holding newborns and (2) was associated with lowest levels of depressive symptoms. Moreover, holding biases were related to maternal depression in bottle-feeding but not in breastfeeding mothers, namely that holding on the right-side while bottle-feeding was associated with higher levels of depressive symptoms. These results were not due to hemispheric specialization as auditory and visual asymmetries were similar between breastfeeding and bottle-feeding mothers. The discussion emphasizes the striking role of the early mother/child relationship's establishment on infant holding biases.     

Knowledge of response location alone is not sufficient to generate social inhibition of return

Previous research has revealed that the inhibition of return (IOR) effect emerges when individuals respond to a target at the same location as their own previous response or the previous response of a co-actor. The latter social IOR effect is thought to occur because the observation of co-actor's response evokes a representation of that action in the observer and that the observation-evoked response code subsequently activates the inhibitory mechanisms underlying IOR. The present study was conducted to determine if knowledge of the co-actor's response alone is sufficient to evoke social IOR. Pairs of participants completed responses to targets that appeared at different button locations. Button contact generated location-contingent auditory stimuli (high and low tones in Experiment 1 and colour words in Experiment 2). In the Full condition, the observer saw the response and heard the auditory stimuli. In the Auditory Only condition, the observer did not see the co-actor's response, but heard the auditory stimuli generated via button contact to indicate response endpoint. It was found that, although significant individual and social IOR effects emerged in the Full conditions, there were no social IOR effects in the Auditory Only conditions. These findings suggest that knowledge of the co-actor's response alone via auditory information is not sufficient to activate the inhibitory processes leading to IOR. The activation of the mechanisms that lead to social IOR seems to be dependent on processing channels that code the spatial characteristics of action.     

Activity engagement is related to level, but not change in cognitive ability across adulthood

It is unclear whether the longitudinal relation between activity participation and cognitive ability is due to preserved differentiation (active individuals have higher initial levels of cognitive ability), or differential preservation (active individuals show less negative change across time). This distinction has never been evaluated after dividing time-varying activity into its two sources of variation: between-person and within-person variability. Further, few studies have investigated how the association between activity participation and cognitive ability may differ from early to older adulthood. Using the PATH Through Life Project, we evaluated whether between- and within-person variation in activity participation was associated with cognitive ability and change within cohorts aged 20-24 years, 40-44 years, and 60-64 years at baseline (n = 7,152) assessed on three occasions over an 8-year interval. Multilevel models indicated that between-person differences in activity significantly predicted baseline cognitive ability for all age cohorts and for each assessed cognitive domain (perceptual speed, short-term memory, working memory, episodic memory, and vocabulary), even after accounting for sex, education, occupational status, and physical and mental health. In each case, greater average participation was associated with higher baseline cognitive ability. However, the size of the relationship involving average activity participation and baseline cognitive ability did not differ across adulthood. Between-person activity and within-person variation in activity level were both not significantly associated with change in cognitive test performance. Results suggest that activity participation is indeed related to cognitive ability across adulthood, but only in relation to the starting value of cognitive ability, and not change over time.     

Two time windows of anisomycin-induced amnesia for inhibitory avoidance training in rats: protection from amnesia by pretraining but not pre-exposure to the task apparatus

We have studied the effect of training conditions on hippocampal protein synthesis-dependent processes in consolidation of the inhibitory avoidance task. Adult male Wistar rats were trained and tested in a step-down inhibitory avoidance task (0.4 mA foot shock, 24 hr training–test interval). Fifteen minutes before or 0, 3, or 6 hr after training, animals received a 0.8-μl intrahippocampal infusion of the protein-synthesis inhibitor anisomycin (80 μg) or vehicle (PBS, pH 7.4). The infusion of anisomycin impaired retention test performance in animals injected 15 min before and 3 hr after the training session, but not at 0 or 6 h post-training. Pretraining with a low foot shock intensity (0.2 mA) 24 hr before training, prevented the amnestic effect of anisomycin injected at 15 min before or 3 hr after training. However, simple pre-exposure to the inhibitory avoidance apparatus did not alter the amestic effects of anisomycin. The results suggest that hippocampal protein synthesis is critical in two periods, around the time of, and 3 hr after training. A prior weak training session, however, which does not itself alter step-down latencies, is sufficient to prevent the amnestic effect of anisomycin, suggesting that even if not behaviorally detectable, weak training must be sufficient to produce some lasting cellular expression of the experience.     

Developmental history and stress responsiveness are related to response inhibition,but not judgement bias,in a cohort of European starlings (Sturnus vulgaris)

Animal Cognition - Judgement bias tasks are designed to provide markers of affective states. A recent study of European starlings (Sturnus vulgaris) demonstrated modest familial effects on...     

Interference suppression vs. response inhibition: An explanation for the absence of a bilingual advantage in preschoolers’ Stroop task performance

The well-documented advantage that bilingual speakers demonstrate across the lifespan on measures of controlled attention is not observed in preschoolers’ performance on Stroop task variations. We examined the role of task demands in explaining this discrepancy. Whereas the Color/Word Stroop used with adult participants requires interference suppression, the Stroop task typically used with preschoolers requires only response inhibition. We developed an age-appropriate conflict task that measures interference suppression. Fifty-one preschool children (26 bilinguals) completed this new Bivalent Shape Task and the Day/Night task used in previous research. Bilingual in comparison to monolingual children performed better on incongruent trials of the Bivalent Shape Task, but did not differ on other measures. The results indicate that the discrepancy between preschoolers and older individuals in performance on Stroop task adaptations results from characteristics of the task rather than developmental differences. Further, the findings provide additional support for the importance of interference suppression as a mechanism underlying the bilingual advantage.     

Agreeableness is related to social‐cognitive,but not social‐perceptual,theory of mind

We hypothesise on a number of grounds that the personality dimension of Agreeableness may be associated with inter‐individual differences in theory of mind (ToM) functioning. However, it is important to distinguish social‐perceptual from social‐cognitive ToM. Previous findings on ToM in psychopathic individuals, sex differences in ToM and the associations between ToM and social relationships, all suggest that social‐cognitive ToM is more likely than social‐perceptual ToM to relate to Agreeableness. In separate empirical studies, we find that Agreeableness is substantially correlated with social‐cognitive ToM performance, but uncorrelated with social‐perceptual ToM performance. We suggest that the propensity or motivation to attend to the mental states of others may be central to the personality dimension of Agreeableness. Copyright © 2008 John Wiley & Sons, Ltd.