A tuned-trace theory of interval-timing dynamics

Animals on interval schedules of reinforcement can rapidly adjust a temporal dependent variable, such as wait time, to changes in the prevailing interreinforcement interval. We describe data on the effects of impulse, step, sine-cyclic, and variable-interval schedules and show that they can be explained by a tuned-trace timing model with a one-back threshold-setting rule. The model can also explain steady-state timing properties such as proportional and Weber law timing and the effects of reinforcement magnitude. The model assumes that food reinforcers and other time markers have a decaying effect (trace) with properties that can be derived from the rate-sensitive property of habituation (the multiple-time-scale model). In timing experiments, response threshold is determined by the trace value at the time of the most recent reinforcement. The model provides a partial account for the learning of multiple intervals, but does not account for scalloping and other postpause features of responding on interval schedules and has some problems with square-wave schedules.     

Associative learning and elemental representation: II. Generalization and discrimination

This paper follows on from an earlier companion paper (McLaren & Mackintosh, 2000), in which we further developed the elemental associative theory put forward in McLaren, Kaye, and Mackintosh (1989). Here, we begin by explicating the idea that stimuli can be represented as patterns of activation distributed across a set of units and that different stimuli activate partially overlapping sets (the degree of overlap being proportional to the similarity of the stimuli). A consequence of this view is that the overall level of activity of some of the units representing a stimulus may be dependent on the nature of the other stimuli present at the same time. This allows an elemental analysis in which provision for the representation of configurations of stimuli is made. A selective review of studies of generalization and discrimination learning, including peak shift, transfer along a continuum, configural discrimination, and summation, suggests that the principles embodied in this class of theory deserve careful consideration and will form part of any successful model of associative learning in humans or animals. There are some phenomena that require an elemental/associative explanation.     

Negative mood,depressive symptoms,and major depression after smoking cessation treatment in smokers with a history of major depressive disorder

Negative mood, depressive symptoms, and major depressive episodes (MDEs) were examined in 179 smokers with a history of major depression in a trial comparing standard smoking cessation treatment to treatment incorporating cognitive-behavioral therapy for depression (CBT-D). Early lapses were associated with relatively large increases in negative mood on quit date. Mood improved in the 2 weeks after quit date among those returning to regular smoking but not among those smoking moderately. Continuous abstinence was associated with short- and long-term reductions in depressive symptoms. MDE incidence during follow-up was 15.3% and was not associated with abstinence. Unexpected was that CBT-D was associated with greater negative mood and depressive symptoms and increased MDE risk. Results suggest complex bidirectional associations between affect and smoking outcomes.     

Children prenatally exposed to maternal anxiety devote more attentional resources to neutral pictures

Maternal anxiety during pregnancy can negatively affect fetal neurodevelopment, predisposing the offspring to a higher risk of behavioral and emotional problems later in life. The current study investigates the association between maternal anxiety during pregnancy and child affective picture processing using event‐related brain potentials (ERPs). Mothers reported anxiety during the second trimester using the anxiety subscale of the Symptom Checklist (SCL‐90). At age 4 years, child affective picture processing (N = 86) was measured by recording ERPs during viewing of neutral, pleasant, and unpleasant pictures selected from the International Affective Pictures System. The late positive potential (LPP)—an ERP component reflecting individual differences in affective processing—was used as child outcome. The expected positive association between maternal anxiety and LPP amplitude for unpleasant pictures was not found. Nevertheless, we found a positive association between maternal anxiety during pregnancy and LPP amplitudes for neutral pictures in the middle and late time window at anterior locations (all p < .05). These associations remained significant after adjusting for maternal postnatal anxiety and gestational age at birth and after FDR correction for multiple comparisons. Our study provides neurophysiological evidence that children prenatally exposed to higher maternal anxiety devote more attentional resources to neutral pictures, but not to unpleasant pictures. Possibly, these children show enhanced vigilance for threat when viewing neutral pictures. Although useful in dangerous environments, this enhanced vigilance may predispose children prenatally exposed to higher maternal anxiety to developing behavioral and/or emotional problems later in life. A video abstract of this article can be viewed at: https://www.youtube.com/watch?v=kEzYi6IS2HA     

Effectiveness of a Comprehensive Worksite Stress Management Program: Combining Organizational and Individual Interventions

A comprehensive worksite stress management program consisting of self-management training and a stressor reduction process was evaluated in a pre-post, treatment-control design in four comparable facilities. Results showed that over a 3-month period those individuals attending self-management training improved on emotional well-being measures. Organizational data suggested that their work-units' productivity increased and absenteeism decreased over the same period. Results support the value of combining self-management training and stressor reduction to produce positive individual and organizational outcomes.     

Temporal manipulation of stimulus patterns using the Apple II: Tachistoscopic and part presentation

A technique is described in which line-drawn pictures can be rapidly interlaced, allowing for sequential part presentation or tachistoscopic presentation on the Apple II. This is accomplished using a two-stage process in which the pictorial stimuli are converted into machine code data files and then used to create a rapidly changing display consisting of two or more line drawings. The latter stage could be accomplished in less than 2 msec but is limited by the frame time of the monitor (17–20 msec).     

Development of Indirect Measures of Conscientiousness: Combining a Facets Approach and Network Analysis

Because indirect measures of personality self‐concepts such as the Implicit Association Test (IAT) allow tapping into automatic processes, they can offer advantages over self‐report measures. However, prior investigations have led to mixed results regarding the validity of indirect measures of conscientiousness. We suggest that these results might be due to a failure to consider the different facets of conscientiousness. These facets are of crucial importance because they are associated differentially with other psychobiological constructs and they are also characterized by different mechanisms. Therefore, focusing on facets while developing indirect measures of conscientiousness may improve the validity of such measures. In Study 1, we conducted a psycholexical investigation to develop one IAT for each conscientiousness facet. In Study 2, we examined the convergent and discriminant validities of each facet IAT in relation to self‐report measures, peer‐report measures and self‐report behavioural indicators, and we investigated differential associations of the conscientiousness facets with working memory capacity and self‐control. We employed network analysis as a novel approach to elucidate differential relationships involving personality facets. The results corroborated the convergent and discriminant validity of the conscientiousness facet IATs with self‐reports and showed that the conscientiousness facets were differentially associated with working memory capacity and with self‐control. Copyright © 2015 European Association of Personality Psychology     

Brain bases of morphological processing in Chinese‐English bilingual children

Can bilingual exposure impact children's neural circuitry for learning to read? To answer this question, we investigated the brain bases of morphological awareness, one of the key spoken language abilities for learning to read in English and Chinese. Bilingual Chinese‐English and monolingual English children (N = 22, ages 7–12) completed morphological tasks that best characterize each of their languages: compound morphology in Chinese (e.g. basket + ball = basketball) and derivational morphology in English (e.g. re + do = redo). In contrast to monolinguals, bilinguals showed greater activation in the left middle temporal region, suggesting that bilingual exposure to Chinese impacts the functionality of brain regions supporting semantic abilities. Similar to monolinguals, bilinguals showed greater activation in the left inferior frontal region [BA 45] in English than Chinese, suggesting that young bilinguals form language‐specific neural representations. The findings offer new insights to inform bilingual and cross‐linguistic models of language and literacy acquisition.     

Parental Stress and Children’s Social and Behavioral Outcomes: The Role of Abuse Potential over Time

Parental stress is a well-established risk factor for adverse child outcomes, including the development of aggression, externalizing behavior problems, and anxiety, as well as compromised emotional coping, impaired social cognition, and diminished treatment response. Abuse potential represents a mechanism by which parental stress may impact child social competence and behavior; evidence links parental stress to abuse potential, and abuse potential to a range of negative child social competence and behavioral outcomes. The current study assessed relationships between parental stress, abuse potential, and child social and behavioral outcomes over time. Parents of children ages 2–6 years (N?=?610, 44% girls) reported on perceived parental stress and attitudes towards abuse and neglect, as well as child social competence and behavior problems, before and after a caregiver-directed, community-based intervention. Changes in parental stress, abuse potential, and child social and behavioral outcomes were examined using panel analyses, while controlling for intervention effects and demographic variables. Parental stress predicted child social competence, anxiety/withdrawal, and anger/aggression over time; while the links between stress and anxiety/withdrawal, and stress and social competence, were mediated by child abuse potential, the link between stress and anger/aggression was not mediated by child abuse potential. Findings suggest that abuse potential represents a mechanism by which parental stress and child social and behavioral outcomes are linked. Further, screening for child social competence deficits may identify children at risk for abuse, as well as parents in need of services to reduce stress.