Biomedical subjects

Steve Stewart-Williams

Publications and source records attributed to Steve Stewart-Williams.

5 recordsLinked to original sources

PubMed2006

Memory deficits in Parkinson's disease.

The purpose of this study was to investigate deficits in recognition, recall, and prospective memory among Parkinson's disease (PD) patients, and to ascertain whether task difficulty and disease severity moderate these deficits. Comparisons were made between 41 nondemented PD participants, divided into early-stage and advanced-stage groups, and 41 matched controls. PD participants exhibited deficits in recognition, recall, and prospective memory. The advanced-stage PD group produced greater deficits than the early-stage PD group in all tasks, suggesting that these deficits increase in step with overall disease severity. The results of the task difficulty manipulation provide a partial explanation for the inconsistencies in the literature concerning the existence of recognition memory deficits in PD.

Aged↗

PubMed2006

Adding insult to injury: development and initial validation of the Partner-Directed Insults Scale.

Women who are verbally abused by their intimate male partners suffer serious mental health consequences and often experience physical violence in their relationship. Despite the importance of studying verbal abuse, no previous research has investigated the specific content of the insults men use to derogate their partners. We present the development and initial validation of a new measure designed to assess the specific content of insults used by men against their intimate partners. In a preliminary study, we used feedback from battered women, along with a review of the relevant literature, to identify specific insults for inclusion in the Partner-Directed Insults Scale (PDIS). We administered the PDIS to a sample of United States participants (Study 1) and a sample of New Zealand participants (Study 2), allowing for a cross-national investigation of the specific insults that men use to derogate their partners. The results demonstrate the practical need for such a scale and provide evidence for the discriminant validity of the PDIS by documenting that men's use of insults predicts their use of controlling behaviors and physical violence.

Adult↗

PubMed2005

Face recognition and aging: effects of target age and memory load.

In the present study, we investigated age-related decline in face recognition memory and whether this decline is moderated by the age of the target faces and by the number of faces that the participant must learn (memory load). Thirty-two participants in each of three age groups (18-39 years, 60-75 years, and 76-96 years) completed a face recognition task. Signal detection analyses confirmed that face recognition accuracy declined with age. However, this finding was qualified by an interaction between participant age and target age, which revealed that the age-related decline in face recognition accuracy occurred only for young target faces. Increased memory load was associated with comparable performance decrements across all age groups. However, memory load appears not to be the cause of these decrements. Instead, they appear to be a product of recognition load (the number of stimuli presented in the recognition phase).

Adolescent↗

PubMed2004

The placebo effect: dissolving the expectancy versus conditioning debate.

The authors review the literature on the 2 main models of the placebo effect: expectancy theory and classical conditioning. A path is suggested to dissolving the theoretical impasse that has long plagued this issue. The key is to make a clear distinction between 2 questions: What factors shape placebo effects? and What learning mediates the placebo effect? The reviewed literature suggests that classical conditioning procedures are one shaping factor but that verbal information can also shape placebo effects. The literature also suggests that conditioning procedures and other sources of information sometimes shape conscious expectancies and that these expectancies mediate some placebo effects; however, in other cases conditioning procedures appear to shape placebo effects that are not mediated by conscious cognition.

Cognition↗

PubMed2004

The placebo puzzle: putting together the pieces.

This article outlines and assesses the main theories of the placebo effect and suggests how they might sit together in a larger model of placebo etiology. Among the approaches considered are expectancy theory, emotional change theory, classical conditioning, and the biological approach. Although these are sometimes assumed to be competing models, in many cases they shed light on different pans of the placebo puzzle. Expectancies are the core of most placebo effects in human beings. The effects of expectancies are sometimes unmediated but in other cases are mediated by changes in emotional state, immune system function, perception, or behavior. Although expectancies are implicated in most placebo effects, a small number of placebo effects may be solely attributable to nonconscious contingency learning.

Affect↗