Age influences domestic dog cognitive performance independent of average breed lifespan

Animal Cognition - Across mammals, increased body size is positively associated with lifespan. However, within species, this relationship is inverted. This is well illustrated in dogs (Canis...     

Selective impairment of lexical stress assignment in an Italian-speaking aphasic patient

Psycholinguistic speech production models assume that lexical stress is stored and accessed separately during phonological encoding. We address the questions of the storage and computation of lexical stress in a case study of an Italian-speaking patient with an impairment of lexical stress assignment in naming, reading, and repeating single words. The patient's stress error pattern and his performance on tasks examining lexical stress in perception suggest an impairment in the retrieval of the stress pattern of irregular words. In contrast, his assignment of stress to nonstored phonological forms suggests that the computation of stress is unimpaired.     

Distress tolerance as a predictor of early treatment dropout in a residential substance abuse treatment facility

A large percentage of individuals who enter residential substance abuse treatment drop out before completing treatment. Given that early treatment dropout places individuals at an increased risk for relapse, identifying the mechanisms underlying treatment dropout would have several important theoretical and clinical implications. In the current study, the authors examined levels of psychological and physical distress tolerance as a predictor of early treatment dropout in a residential substance abuse treatment facility. In a sample of 122 individuals entering a residential substance abuse treatment facility, level of psychological distress tolerance was predictive of early treatment dropout above and beyond relevant self-report variables. There was no relationship between physical distress tolerance and early treatment dropout. Implications for future studies and treatment development or modification are discussed.     

Effects of reinforcement history on response rate and response pattern in periodic reinforcement

Several researchers have suggested that conditioning history may have long-term effects on fixed-interval performances of rats. To test this idea and to identify possible factors involved in temporal control development, groups of rats initially were exposed to different reinforcement schedules: continuous, fixed-time, and random-interval. Afterwards, half of the rats in each group were studied on a fixed-interval 30-s schedule of reinforcement and the other half on a fixed-interval 90-s schedule of reinforcement. No evidence of long-term effects attributable to conditioning history on either response output or response patterning was found; history effects were transitory. Different tendencies in trajectory across sessions were observed for measures of early and late responding within the interreinforcer interval, suggesting that temporal control is the result of two separate processes: one involved in response output and the other in time allocation of responding and not responding.     

The dynamics of self-esteem in adults over a 6-month period: an exploratory study

In this exploratory study, the authors examined the dynamics of self-esteem in 8 adults over a 6-month period. Each participant (M age = 29.4 years, SD = 7.9, SEM = 2.8) completed a single item from the Physical Self Inventory (G. Ninot, M. Fortes, & D. Delignières, 2001) using a 10-cm visual analog scale (horizontal line), twice a day between 7:00 and 9:00 a.m. and between 7:00 and 9:00 p.m. Time series analyses, including autocorrelation and autoregressive integrated moving average (ARIMA) procedures, showed that global self-esteem dynamics were neither stable, stationary, nor random. The ARIMA procedures indicated that this perceived dimension functioned as a moving average (0, 1, 1) without a significant constant, thus suggesting a short-term dynamic adjustment. This pattern is a typical signature of a complex system submitted to several constraints and not an indication of personality trait or state.     

Toddlers' representations of space: the role of viewer perspective

In the present study, we examined how people code object location when an object is hidden in an enclosed space. On object location tasks involving disorientation, viewers must code the location of an object in relation to the spatial environment because they cannot directly track their changing relation to the object. Recently, we showed that viewers also code their perspective relative to the entire space (inside vs. outside) in such tasks. To determine whether viewers code perspective whenever they must locate an object, we examined young children's performance on a task in which coding perspective would be difficult. Our task involved both disorientation and translation (i.e., movement from inside to outside the space or vice versa). When translation preceded disorientation, performance was comparable to performance on tasks with no translation. However, when disorientation preceded translation, performance was at chance. The implications of these findings for location coding are discussed.     

The relationship between active hand and ear advantage in the native and foreign language

In an experimental design involving two auditorily presented competing commands (one to each ear), 144 right-handed subjects (72 male and 72 female) were asked to provide motor responses. Half of each group of subjects was responding with their right hand and the other half with the left. The test was applied in the subjects' native language (Croatian) and in English, which they had learned as a foreign language. Ear advantage was determined by calculating laterality indices from the order of responding to the commands. On average, right-ear advantage was found in all conditions. Analysis of results revealed the effect of the active hand in Croatian (with significant decrease in the right-ear advantage when using the left hand). The same trend failed to reach significance in English. In responses to English stimuli, there was a significant effect of gender (with men exhibiting a lower right-ear advantage than women). The same trend was not significant for Croatian stimuli. The consistently lower right-ear advantage found in male subjects is contrary to the traditional assumptions that men are more lateralized than women and warrants further investigation.     

Predictors of picture naming speed

We report the results of a large-scale picture naming experiment in which we evaluated the potential contribution of nine theoretically relevant factors to naming latencies. The experiment included a large number of items and a large sample of participants. In order to make this experiment as similar as possile to classic picture naming experiments, participants were familiarizedwith the materials during a training session. Speeded naming latencies were determined by a software key on the basis of the digital recording of the responses. The effects of various variables on these latencies were assessed with multiple regression techniques, using a repeated measures design. The interpretation of the observed effects is discussed in relation to previous studies and current views on lexical access during speech production.     

Inhibitory attentional control in patients with frontal lobe damage

The performance of a group of frontal lobe lesion and a group of frontal lobe dementia patients was compared with the performance of their respective matched normal control groups on two tests of inhibitory attentional control-the stop-signal reaction time task and a negative priming task. Both patient groups responded significantly slower than their respective normal control groups, but they showed only marginally significant selective impairments on the measures of inhibition. The data suggest that the specific inhibitory processes evaluated by these two tests are, in general, spared in patients with focal frontal lobe lesions or frontal lobe degeneration.