Divergent effects of healthy ageing on semantic knowledge and control: Evidence from novel comparisons with semantically impaired patients

Effective use of semantic knowledge requires a set of conceptual representations and control processes which ensure that currently relevant aspects of this knowledge are retrieved and selected. It is well-established that levels of semantic knowledge increase across the lifespan. However, the effects of ageing on semantic control processes have not been assessed. I addressed this issue by comparing the performance profiles of young and older people on a verbal comprehension test. Two sets of variables were used to predict accuracy and RT in each group: (1) the psycholinguistic properties of words probed in each trial and (2) the performance on each trial by two groups of semantically impaired neuropsychological patients. Young people demonstrated poor performance for low-frequency and abstract words, suggesting that they had difficulty processing words with intrinsically weak semantic representations. Indeed, performance in this group was strongly predicted by the performance of patients with semantic dementia, who suffer from degradation of semantic knowledge. In contrast, older adults performed poorly on trials where the target semantic relationship was weak and distractor relationships strong – conditions which require high levels of controlled processing. Their performance was not predicted by the performance of semantic dementia patients, but was predicted by the performance of patients with semantic control deficits. These findings indicate that the effects of ageing on semantic cognition are more complex than has previously been assumed. While older people have larger stores of knowledge than young people, they appear to be less skilled at exercising control over the activation of this knowledge.     

Protective Factors for Suicidal Black Females

The purpose of this study is to evaluate the extent to which a model of social support may help explain the low suicide rate of Black females. The data are taken from the National Institute of Mental Health's Epidemiologic Catchment Area Study 1980–1985 (United States). The LISREL model examines the direct and indirect effects of the background characteristics on attempted suicide as mediated by emotional state. Results indicate evidence that for Black and White males and females, finding emotional and psychological support in friends and family members helps to safeguard against suicide. The most substantial finding is that for all race/sex categories, seeking support from friendship and familial resources is negatively related to attempted suicide, whereas seeking support from professional resources is associated with an increase in the likelihood of a suicide attempt. This increased likelihood of attempted suicide may be reflecting populations members' resistance to seeking professional help until their emotional state has severely deteriorated.     

Standards of Care: Potential Implications for the Counseling Profession

The potential implications for development of professionally defined “standards of care” treatment procedures for mental health counseling are presented. The role of xpert witnesses in malpractice cases is examined as one source from which the standards are currently derived. The influence of managed care on the current clinical practices is noted. Finally, the importance of using outcome research as the basis for developing a “best practices” concept of standards of care is discussed. The authors note difficulties and challenges involved in making a commitment to what could be the next major impetus to the mental health movement.