Letters to the Editor Department

Letter to the Editor

Letters to the Editor Department     

Varying intertrial interval reveals temporally defined memory deficits and enhancements in NTAN1-deficient mice

The N-end rule is one ubiquitin-proteolytic pathway that relates the in vivo half-life of a protein to the identity of its N-terminal residue. NTAN1 deamidates N-terminal asparagine to aspartate, which is conjugated to arginine by ATE1. An N-terminal arginine-bearing substrate protein is recognized, ubiquitylated by UBR1/E3α, and subsequently degraded by 26S proteasomes. Previous research showed that NTAN1-deficient mice exhibited impaired long-term memory in the Lashley III maze. Therefore, a series of studies, designed to assess the role of NTAN1 in short- and intermediate-term memory processes, was undertaken. Two hundred sixty mice (126 −/−; 134 +/ +) received Lashley III maze training with intertrial intervals ranging from 2–180 min. Results indicated that inactivation of NTAN1 amidase differentially affects short-, intermediate-, and long-term memory.     

Alcohol use and depression among African-American and Caucasian adolescents

The purpose of this study was to determine differences in reported alcohol use and depressive symptomatology among a sample of 524 African-American and Caucasian adolescents. Of specific interest was determining if ethnicity, gender, and age predicted severity of scores obtained on the Reynolds Adolescent Depression Scale (RADS) and Adolescent Drinking Index (ADI). Extreme groups were formed using upper (> 75%) and lower (< 25%) quartiles. Three other groups were formed using each instrument's normatively derived cutoff scores: depressed only (RADS > 77), heavy drinking (ADI > 16) and mixed (RADS > 77, ADI > 16). Several results were obtained. First, Caucasians obtained significantly higher scores on the ADI than African-Americans, although no differences were obtained for the RADS. Females scored higher on the RADS but lower on the ADI than males. In terms of extreme scores, females were less likely to belong to the severe depression group, while older adolescents in general and African-Americans in particular had a greater probability of belonging to the heavy-drinking group. Finally, using RADS and ADI cutoff scores, females were less likely than males to belong to the depression only group as were African-Americans. Older adolescents, in general, and African-Americans in particular had a greater probability of belonging to the mixed group than did their counterparts.     

Body checking and avoidance and the core features of eating disorders among obese men and women seeking bariatric surgery

This study examined two aspects of body checking and avoidance, and their relations to the core psychopathology of eating disorders (EDs), in severely obese men and women seeking bariatric surgery. A consecutive series of 260 (44 male and 216 female) gastric bypass candidates were administered measures to assess body checking and avoidance, binge eating, restraint, and overevaluation of weight and shape. The majority of patients reported regularly pinching areas of their body to check for fatness and avoided wearing clothing that made them particularly aware of their body. Significant associations were observed between checking and restraint, and between avoidance and binge eating. Both checking and avoidance behaviors were significantly associated with overevaluation of weight and shape. The positive associations between each of the two behaviors (body checking and avoidance) with overevaluation of weight/shape remained significant even after controlling for the effects of avoidance on body checking and vice versa. Stepwise multiple regression analyses revealed that binge eating, body checking, and avoidance behaviors made significant unique contributions and jointly accounted for 22-25% of the variance in overevaluation of weight and shape, respectively. This study documents the presence of eating disorder psychopathology among severely obese patients seeking bariatric surgery. The findings support the view that body checking and avoidance behaviors are manifestations of overevaluation of weight and shape and disordered eating.     

The course of depressive symptoms in men from early adolescence to young adulthood: identifying latent trajectories and early predictors

Heterogeneity in the longitudinal course of depressive symptoms was studied through the use of general growth mixture modeling for young men in the Oregon Youth Study (N=206), who ranged in age from 15 to 24 years. Four trajectory classes were identified: the very-low, the moderate-decreasing, the high-decreasing, and the high-persistent classes. The 3 lowest classes differed primarily quantitatively with the initial level or mean level across time being the major determinant of class differences, whereas the high-persistent class appeared qualitatively different in terms of long-term developmental trends and variation. Findings from univariate and multivariate analyses revealed specific effects of childhood, parental, contextual, and individual risk factors on the class membership as well as on the growth within each trajectory class.     

The effects of universal pre-K on cognitive development

In this study of Oklahoma's universal pre-K program, the authors relied on a strict birthday eligibility criterion to compare "young" kindergarten children who just completed pre-K to "old" pre-K children just beginning pre-K. This regression-discontinuity design reduces the threat of selection bias. Their sample consisted of 1,567 pre-K children and 1,461 kindergarten children who had just completed pre-K. The authors estimated the impact of the pre-K treatment on Woodcock-Johnson Achievement test scores. The authors found test impacts of 3.00 points (0.79 of the standard deviation for the control group) for the Letter-Word Identification score, 1.86 points (0.64 of the standard deviation of the control group) for the Spelling score, and 1.94 points (0.38 of the standard deviation of the control group) for the Applied Problems score. Hispanic, Black, White, and Native American children all benefit from the program, as do children in diverse income brackets, as measured by school lunch eligibility status. The authors conclude that Oklahoma's universal pre-K program has succeeded in enhancing the school readiness of a diverse group of children.     

The impact of justice climate and justice orientation on work outcomes: a cross-level multifoci framework

In this article, which takes a person-situation approach, the authors propose and test a cross-level multifoci model of workplace justice. They crossed 3 types of justice (procedural, informational, and interpersonal) with 2 foci (organization and supervisor) and aggregated to the group level to create 6 distinct justice climate variables. They then tested for the effects of these variables on either organization-directed or supervisor-directed commitment, satisfaction, and citizenship behavior. The authors also tested justice orientation as a moderator of these relationships. The results, based on 231 employees constituting 44 work groups representing multiple organizations and occupations, revealed that 4 forms of justice climate (organization-focused procedural and informational justice climate and supervisor-focused procedural and interpersonal justice climate) were significantly related to various work outcomes after controlling for corresponding individual-level justice perceptions. In addition, some moderation effects were found. Implications for organizations and future research are discussed.     

The multidimensional nature of ageism: construct validity and group differences

The authors investigated the factor structure and construct validity of the Fraboni Scale of Ageism and the age and gender differences in ageism scores. Confirmatory factor analyses supported the multidimensional nature of FSA scores and generally corroborated the initial factor structure reported by M. Fraboni, with some notable exceptions. Essentially, the present findings were aligned with theoretical models of ageism that emphasize both cognitive facets and affective facets. That is, on the basis of their factor analytic findings, the authors redefined Fraboni's original factors of Antilocution, Avoidance, and Discrimination as Stereotypes, Separation, and Affective Attitudes, respectively, because of the clustering of items within factors. The revised 3-factor structure accounted for 36.4% of the variance in FSA scores. FSA factor scores significantly related to other scores from other measures of age-related attitudes, with higher correlations among factors that were similar in terms of their cognitive nature versus their affective nature. Finally, younger individuals and men had significantly higher ageism scores on the FSA than older individuals and women. The authors discussed the importance of adequately assessing ageism, with particular emphasis devoted to the understanding of age bias.     

Straightness as a cue for luminance edge interpretation

In order to determine the reflectance of a surface, it is necessary to discount luminance changes produced by illumination variation, a process that requires the visual system to respond differently to luminance changes that are due to illumination and reflectance. It is known that various cues can be used in this process. By measuring the strength of lightness illusions, we find evidence that straightness is, used as a cue: When a boundary is straight rather than curved, it has a greater tendency to be discounted, as if it were an illumination edge. The strongest illusions occur when a boundary has high contrast and has multiple X-junctions that preserve a consistent contrast ratio.     

The relationship between short-term memory and working memory: complex span made simple?

This experiment addresses the question of what makes a working memory measure a good predictor of higher-level abilities. Verbal and visuospatial processing episodes were interleaved with distinct verbal and visuospatial storage episodes to form four complex span tasks. Although these measures were reliable predictors of reading and mathematics ability in children, they were no more predictive of these abilities than corresponding simple span tasks involving storage alone. However, when individual differences in storage ability and processing capacity were controlled for, residual variance in complex span performance was related to academic ability in some cases. These findings indicate that complex span tasks are multiply determined, and that differences in task structure can dramatically influence the relative importance of these multiple constraints and the predictive power of a complex span measure.