Perception of Temporal Order: The Effects of Age,Sex, and Cognitive Factors

ABSTRACT

The present paper investigates the effects of age, sex, and cognitive factors on temporal-order perception. Nine temporal-order tasks were employed using two and four stimuli presented in the auditory and visual modalities. Significantly increased temporal-order thresholds (TOT) in the elderly were found for almost all tasks, while sex differences were only observed for two tasks. Multiple regression analyses show that the performance on most temporal-order tasks can be predicted by cognitive factors, such as speed of fluid reasoning, short-term memory, and attention. However, age was a significant predictor of TOT in three tasks using visual stimuli. We conclude (1) that age-related differences can often be attributed to cognitive factors involved in temporal-order perception, and (2) that the concept of temporal-order perception is more complex than implied by the current models.     

Commission errors of active intentions: the roles of aging,cognitive load,and practice

Performing an intended action when it needs to be withheld, for example, when temporarily prescribed medication is incompatible with the other medication, is referred to as commission errors of prospective memory (PM). While recent research indicates that older adults are especially prone to commission errors for finished intentions, there is a lack of research on the effects of aging on commission errors for still active intentions. The present research investigates conditions which might contribute to older adults’ propensity to perform planned intentions under inappropriate conditions. Specifically, disproportionally higher rates of commission errors for still active intentions were observed in older than in younger adults with both salient (Experiment 1) and non-salient (Experiment 2) target cues. Practicing the PM task in Experiment 2, however, helped execution of the intended action in terms of higher PM performance at faster ongoing-task response times but did not increase the rate of commission errors. The results have important implications for the understanding of older adults’ PM commission errors and the processes involved in these errors.     

Psychometric Properties of Various Scales Measuring Psychological Well-Being in a South African Context: The FORT 1 Project

The aim of this study was to do a first phase screening of psychometric properties of various scales measuring facets of psychological well-being so as to address further questions in the FORT 1 project (FORT 1 = Clarifying the nature of psychological strengths). All scales (except one) were developed in a Western context, and measure facets of cognitive, affective, conative, social, and spiritual psychological well-being. As it could not be assumed that scales are valid in South African contexts, a broad screening of their psychometric properties was necessary before specific questions could be adressed. A convenience sample (N=514) including white (n=384) and black (n=130) students and adults from the North West Province and Gauteng areas completed all questionnaires. Psychometric properties of scales varied from acceptable to unacceptable for use in a specific subgroup.     

Visual event-related potentials of dogs: a non-invasive electroencephalography study

Previously, social and cognitive abilities of dogs have been studied within behavioral experiments, but the neural processing underlying the cognitive events remains to be clarified. Here, we employed completely non-invasive scalp-electroencephalography in studying the neural correlates of the visual cognition of dogs. We measured visual event-related potentials (ERPs) of eight dogs while they observed images of dog and human faces presented on a computer screen. The dogs were trained to lie still with positive operant conditioning, and they were neither mechanically restrained nor sedated during the measurements. The ERPs corresponding to early visual processing of dogs were detectable at 75–100 ms from the stimulus onset in individual dogs, and the group-level data of the 8 dogs differed significantly from zero bilaterally at around 75 ms at the most posterior sensors. Additionally, we detected differences between the responses to human and dog faces in the posterior sensors at 75–100 ms and in the anterior sensors at 350–400 ms. To our knowledge, this is the first illustration of completely non-invasively measured visual brain responses both in individual dogs and within a group-level study, using ecologically valid visual stimuli. The results of the present study validate the feasibility of non-invasive ERP measurements in studies with dogs, and the study is expected to pave the way for further neurocognitive studies in dogs.     

The self in the couple relationship: part 2

Part 1 of this paper examined some of the ways in which individual therapy, by assisting in the development of a more cohesive sense of self in the individual, inevitably has an impact on the individual's relationships, especially their relationship with a partner. This paper approaches the topic of the significance of ‘the self’ in the couple relationship from an alternative direction. It focuses on the significance of ‘the self’ for couples therapy, and argues that couples therapy may sometimes need to include therapeutic work with one partner to facilitate change in the relationship. In both parts of the paper, a conceptualization of the couple relationship as ‘a transitional space’ is central.     

Mood state,task demand,and effort-related cardiovascular response

Drawing on the mood-behaviour model (Gendolla, 2000), two studies investigated informational effects of mood on effort-related cardiovascular response. Experiment 1 manipulated mood state (positive, negative) and task difficulty (easy, difficult, extremely difficult). Effects on cardiovascular reactivity were as expected: On the easy level, reactivity was weak in a positive mood, but strong in a negative mood; on the difficult level, reactivity was strong in a positive mood, but weak in a negative mood; on the extremely difficulty level mood had no effect. Experiment 2 manipulated mood only. As predicted, subjective demand and cardiovascular response were both higher in a negative mood than in a positive mood and the mood effect on cardiovascular response diminished after statistically controlling for the demand appraisals. Neither study revealed any mood effects on cardiovascular response during the mood inductions.     

Attentional capture by signals of threat

Attention can be captured automatically by events that are physically salient. Similarly, emotional stimuli are known to be prioritised by the visual system because of their behavioural significance. The present study investigated whether a neutral stimulus which became associated with fear captured attention in visual search. Using a fear-conditioning procedure, one stimulus was repeatedly combined with an electrical shock (CS+), whereas another stimulus with identical physical features was never combined with a shock (CS?). Following conditioning, participants had to search for a target; while on some trials, either an irrelevant CS+ or CS? stimulus was present. The results show that the presence of an irrelevant distractor that was previously associated with fear slowed a search more than a distractor without fear association. The current results indicate that learned fear associations have the ability to capture our attention even if we try to ignore them.