Aging, working memory, and discrimination learning

Older adults easily learn probabilistic relationships between cues and outcomes when the predictive event is the occurrence of a cue, but have greater difficulty when the predictive event is the nonoccurrence of a cue (Mutter & Pliske, 1996; Mutter & Plumlee, 2004; Mutter & Williams, 2004). This study explored whether this age-related deficit occurs in a simpler learning context and whether it might be related to working memory (WM) decline. We gave younger and older adults simultaneous discrimination tasks that allowed us to compare their ability to learn deterministic relationships when either the occurrence (feature positive; FP) or the nonoccurrence (feature negative; FN) of a distinctive feature predicted reinforcement. We also included a group of younger adults who performed the discrimination tasks under a concurrent WM load. Both age and WM load had a detrimental effect on initial FP and FN discrimination; however, these effects persisted only in FN discrimination after additional learning experience. Learning predictive relationships requires inductive reasoning processes that apparently do not operate as efficiently in individuals with reduced WM capacity. The impact of WM decline may ultimately be greater for negative cue-outcome relationships because learning these relationships requires more difficult inductive reasoning processes, which place greater demands on WM.     

A Descriptive Study of Pain and Quality of Life following Guillain-Barré Syndrome: One Year Later

Guillain-Barré syndrome (GBS) is a debilitating immunopathy that afflicts approximately 5,000 patients annually in the United States, a number that represents roughly half of the incidence of spinal cord injuries (J. M., Meythaler, 1997). Of these 5,000 new cases per year, 4–15% will die, 20% will possess deficits in ambulation or require ventilator assistance more than one year later, and more than two-thirds will have persistent fatigue (J. M., Meythaler, 1997; Hughes et al., 2003). These figures suggest that GBS is currently a legitimate cause of long-term disability.Many secondary complications may follow GBS that include dysautonomia, deep vein thrombosis, anemia, immobilization, and pain and sensory involvement (J. M., Meythaler, 1997; J. M. Meythaler, M. J. De Vivo, and W. C. Braswell, 1997). These medical complications have not been studied systematically, and the psychosocial complication of pain following GBS has certainly been overlooked in the literature. The present paper utilized a limited sample of 18 patients (N = 18) with persistent motor deficits at least one year after onset of GBS. We examined their pain and perceived quality of life as part of an ongoing federally funded study which will ultimately attempt to determine if 4-aminopyridine (4-AP) significantly improves motor function in patients with residual weakness from GBS. Findings suggest that while most persons do not rate themselves as depressed one year after GBS onset, 22% of respondents did exceed the cutoff for clinical depression on the CES-D. Age and gender do not appear to be related to any component of pain in GBS; however, self-ratings of physical and mental health do appear to be significantly related to pain experience. The nature of this relationship was not determined, and merits further investigation in future studies.     

Subversive Redemption in Psychoanalysis

Subversive redemption—the sense of overturning the conventional order of things in order to recover lost parts of the self—is a virtually neglected topic in psychoanalysis. With free association, Freud empowered patients to harness unconventional thoughts and feelings. Patients who engage in subversive redemption frequently have a strong sense of agency prompting them to open up in new ways in lieu of “playing it safe.” When patients begin to express certain forbidden ideas, the boundaries of analysis are broadened, freeing the analytic pair to become fully authentic. Psychoanalysis provides patients with an arena to renew themselves as they risk “killing off” their status quo positions to achieve the paradox of living more dangerously in the safety of the analytic surrounds. Patients then feel more confident about undertaking the process of subversive redemption in the wider world.     

Orientation discrimination across the visual field: size estimates near contrast threshold

Performance in detection and discrimination tasks can often be made equal across the visual field through appropriate stimulus scaling. The parameter E2 is used to characterize the rate at which stimulus dimensions (e.g., size or contrast) must increase in order to achieve foveal levels of performance. We calculated both size and contrast E2 values for orientation discrimination using a spatial scaling procedure that involves measuring combination size and contrast thresholds for stimuli with constant size-to-contrast ratios. E2 values for size scaling were 5.77 degrees and 5.92 degrees. These values are three to four times larger than those recovered previously using similar stimuli at contrasts well above detection threshold (Sally & Gurnsey, 2003). E2 values for contrast scaling were 324.2 degrees and 44.3 degrees, indicating that for large stimuli little contrast scaling (.3% to 2.3% increase) was required in order to equate performance in the fovea and the largest eccentricity (10 degrees). A similar pattern of results was found using a spatial scaling method that involves measuring contrast thresholds for target identification as a function of size across eccentricities. We conclude that the size scaling for orientation discrimination at near-threshold stimulus contrasts is much larger than that required at suprathreshold contrasts. This may arise, at least in part, from contrast-dependent changes in mechanisms that subserve task performance.     

Knowledge and fear of developing Alzheimer's disease in a sample of healthy adults

Alzheimer's disease is the fourth leading cause of death among seniors but its insidious onset makes it difficult to distinguish from age-related decline and little is known about how much knowledge and fear people entertain about this disease. This study examined knowledge and fear of Alzheimer's disease by surveying 127 young (M= 19.6 yr.) and 118 older (M=67.9 yr.) participants. Younger participants obtained a score of 64%, while older participants obtained 58% on the knowledge test. Younger participants reported significantly higher fear overall. Knowledge and Fear scores were not significantly correlated with having a family member or knowing someone with Alzheimer's disease.     

Temporal stability of the Francis Scale of Attitude toward Christianity short-form: test-retest data over one week

This study evaluated the test-retest reliability of the Francis Scale of Attitude toward Christianity short-form. 39 Northern Irish undergraduate students completed the measure on two occasions separated by one week. Stability across the two administrations was high, r = .92, and there was no significant change between Time 1(M = 25.2, SD = 5.4) and Time 2 (M = 25.7, SD = 6.2). These data support the short-term test-retest reliability of the Francis Scale of Attitude toward Christianity short-form.     

The effects of a mentoring program on at-risk youth

This study examined an intensive mentoring program that focuses on youth deemed at-risk for juvenile delinquency or mental illness. Mothers and teachers completed the Child Behavior Checklist, and youth completed the Hopelessness Scale for Children, the Piers-Harris Self-Concept Scale, and the Self-Report Delinquency Scale. The youth (ages 10 to 17) either participated in the mentoring program (intervention, n = 34) or remained on the waiting list (nonintervention, n = 34) for 6 months. Repeated-measures ANOVAs assessed changes from preintervention to postintervention and indicated significant improvement in problematic behaviors for the intervention group. Mentoring appeared to affect African American youth differently than Caucasian and Latino youth. There were no significant interactions involving gender. The findings of this study supported the positive influence of mentoring on at-risk youth.     

The importance of irrelevant-dimension variability in the stroop flanker task

Two experiments in which the Stroop flanker task was used were conducted in order to examine the influence of irrelevant dimension invariance on congruency effects. Participants responded manually to a central color patch flanked by a Stroop stimulus. In Experiment 1, invariance in flanker location was found to have no influence on word and color congruency effects. In contrast, invariance of flanker identity led to the disappearance of congruency effects. Experiment 2 indicated that the elimination of a congruency effect was restricted to the dimension that remained constant and did not influence the congruency effect of the other dimension that was presented at the same location. Results suggest that variance is a prerequisite to congruity effects, determining the activation of irrelevant dimensions.