The interval for interference in conscious visual imagery

Three experiments are described that use dynamic visual noise (DVN) to interfere with words processed under visual and verbal processing instructions. In Experiment 1 DVN is presented to coincide with the encoding of the words or to coincide with the interval between encoding and recall. The results show that while DVN is a robust disruptor when it is applied during encoding to words processed under visual instruction, it has no effect during encoding when the words are processed under rote instruction. Moreover, DVN has no effect when it is applied during the retention interval, no matter what means are employed to encode the words. Experiment 2 extends these findings by again showing no effect of DVN during the retention interval, yet showing robust interference effects for visually processed words during recall. Finally, Experiment 3 demonstrates that the results of Experiments 1 and 2 cannot be explained by a difference in the time duration associated with application of DVN during the retention interval compared to during encoding and recall. Moreover, the differing decay functions for visually and verbally processed words during the intervals used in Experiment 3 suggest that any failure to cause interference is not because the two processing instructions resulted in words being retained in the same medium. The functions are consistent with word storage mechanisms reflecting appropriately verbal and visual properties. The results are discussed in terms of current models of visual working memory. It is argued that a full interpretation of the results requires a buffer mechanism as an important component of any model of visual working memory.     

Emergence of Joint Attention: Relationships Between Gaze Following,Social Referencing,Imitation, and Naming in Infancy

The authors investigated the extent to which the joint-attention behaviors of gaze following, social referencing, and object-directed imitation were related to each other and to infants' vocabulary development in a sample of 60 infants between the ages of 8 and 14 months. Joint-attention skills and vocabulary development were assessed in a laboratory setting. Split-half reliability analyses on the joint-attention measures indicated that the tasks reliably assessed infants' capabilities. In the main analysis, no significant correlations were found among the joint-attention behaviors except for a significant relationship between gaze following and the number of names in infants' productive vocabularies. The overall pattern of results did not replicate results of previous studies (e.g., M. Carpenter, K. Nagell, & M. Tomasello, 1998) that found relationships between various emerging joint-attention behaviors.     

Explaining Addiction: How Far Does the Reward Account of Motivation Take Us?

ABSTRACT

Choice theorists such as George Ainslie and Gene Heyman argue that the drug-seeking behaviour of addicts is best understood in the same terms that explain everyday choices. Everyday choices, they claim, aim to maximise the reward from available incentives. Continuing drug-use is, therefore, what addicts most want given the incentives they are aware of but they will change their behaviour if and when better incentives become available. This model might explain many typical cases of addiction, but there are hard cases that pose a problem. In these hard cases the addicted individual does not cease using drugs in the face of consequences that are so adverse it is implausible that they are unaware of more rewarding paths of action. These cases force the choice theorist into a dilemma: either these addicts’ drug use does not count as action and so is best described by a neurobiological model, or reference to ‘reward’ in these cases means merely ‘motivated’ and so provides no explanatory power. We propose a different model of motivation that takes self-conception into account. We show how that can better explain the hard cases of addiction and also inform our understanding of recovery and self-control.     

Addressing Anger,Stress, and Alcohol-Related Difficulties in the Military: An ACT Intervention

The use of alcohol to manage emotion is a common technique seen in military service personnel, the implication of which is evident in the relationship between alcohol misuse and mood disorders. However, investigations into transdiagnostic treatments aimed at addressing the common underlying processes to these problems in military personnel are lacking. The present study aimed to investigate the efficacy of a real-world Acceptance and Commitment Therapy (ACT)-based intervention undergone by 262 military personnel. A quasi-experimental prepost design was employed (interim 1 month postintervention) with a waitlist control group utilized to compare differences over time between those who promptly completed the week-long intervention course and the delayed waitlist participants. In line with predictions, the intervention group showed greater improvement (cf. preintervention waitlist group) in emotion management, and greater reductions in levels of alcohol consumption, aggression, anxiety, stress, and perceptions of others being responsible for their circumstances. No significant differences were found in the comparison of both groups’ 1-month postintervention results (i.e., both groups evidenced similar improvements); suggesting having to wait to start the course had little effect on its impact. The results suggest the course holds promise for helping military service personnel improve a range of psychosocial outcomes. Further testing with a more rigorous methodology is recommended, as is using a more proactive approach in the promotion and implementation of future courses.     

A New Measure of Introversion-Extroversion

Five groups of grade school children (N = 237) were selected and administered the Torrance Tests of Creative Thinking. The five groups included urban-middle income children (N = 47), urban-lower income children (N = 49), rural children (N = 72), Indian-lower income children (N = 54), and Indian-impoverished children (N = 15). Significant differences were found on all three measures of verbal creativity, with the verbal flexibility and verbal originality measures significant at the .001 level, and the verbal fluency measure significant at the .005 level. On all three measures, the groups scored from high to low in the following order: rural, urban-middle income, urban-lower income, Indian-lower income, and Indian-impoverished. None of the four measures of figural creativity showed significant differences.     

The effect of overlearning on long‐term retention

Once material has been learned to a criterion of one perfect trial, further study within the same session constitutes overlearning. Although overlearning is a popular learning strategy, its effect on long‐term retention is unclear. In two experiments presented here, 218 college students learned geography facts (Experiment 1) or word definitions (Experiment 2). The degree of learning was manipulated and measured via multiple test‐with‐feedback trials, and participants returned for a final cued recall test between 1 and 9 weeks later. The overlearners recalled far more than the low learners at the 1‐week test, but this difference decreased dramatically thereafter. These data suggest that overlearning (and its concomitant demand for additional study time) is an inefficient strategy for learning material for meaningfully long periods of time. Copyright © 2004 John Wiley & Sons, Ltd.     

Sleep-Related Problems in Pediatric Obsessive-Compulsive Disorder and Intensive Exposure Therapy

Limited research has examined sleep-related problems (SRPs) among children and adolescents with obsessive-compulsive disorder (OCD). The present study addresses this gap by investigating preliminary associations between SRPs, demographic factors (gender and age), family variables (family accommodation and parental stress), and clinical factors (medication status, internalizing and externalizing symptoms, OCD severity, OCD-related impairment), and treatment outcomes in a sample of 103 youth (aged 7 to 17 years; 53% female) with a primary diagnosis of OCD. Clinician, parent, and child measures were used to assess demographic, family, and clinical predictors. SRPs were assessed using an 8-item measure comprising items of the Child Behaviour Checklist, Child Depression Inventory, and Multidimensional Anxiety Scale for Children as used in previous studies. Results showed that SRPs were highly prevalent among this sample and that more SRPs were associated with younger age, internalizing problems, and functional impairment. However, SRPs were not an independent predictor of OCD severity, impairment, or treatment response. Preliminary findings suggest that SRPs among youth with OCD may be more strongly associated with broader internalizing symptoms than with OCD itself. Future longitudinal research is warranted to further explore the complexity of SRPs when co-occurring with pediatric OCD.     

The "ticktock" of our internal clock: direct brain evidence of subjective accents in isochronous sequences

The phenomenon commonly known as subjective accenting refers to the fact that identical sound events within purely isochronous sequences are perceived as unequal. Although subjective accenting has been extensively explored using behavioral methods, no physiological evidence has ever been provided for it. In the present study, we tested the notion that these perceived irregularities are related to the dynamic deployment of attention. We disrupted listeners' expectancies in different positions of auditory equitone sequences and measured their responses through brain event-related potentials (ERPs). Significant differences in a late parietal (P3-like) ERP component were found between the responses elicited on odd-numbered versus even-numbered positions, suggesting that a default binary metric structure was perceived. Our findings indicate that this phenomenon has a rather cognitive, attention-dependent origin, partly affected by musical expertise.