Developments in long-term explicit memory late in the first year of life: behavioral and electrophysiological indices

Coincident with developments in the temporal-cortical explicit memory network, long-term recall abilities are newly emergent late in the first year of human life. We recorded event-related potentials (ERPs) in 9-month-olds as an index of the integrity of the neural substrate underlying a task thought to reflect explicit memory, namely, deferred imitation. ERP measures of recognition memory 1 week after unique laboratory experiences predicted whether and how much infants recalled of the experiences 1 month later. The findings further imply that memory storage and consolidation processes are a major source of variability in long-term recall memory late in the first year of life.     

Inhibition and working memory: effect of acute sleep deprivation on a random letter generation task]

The literature contains inconsistent data on the effects of acute sleep deprivation on the superior cognitive functions. The primary purpose of this study is to determine the effectiveness of inhibition, one of the functions of the working memory executive centre (EC), over an extended, 36-hour waking period. Inhibition is a cognitive mechanism whereby individuals ignore non-relevant information recorded in their working memory. We also tested the effects of a 36-hour period of acute sleep deprivation on simple reaction time. Twelve young, healthy volunteers (M = 21.5 years, sigma = 2.3) performed a random generation task involving letters and a simple reaction time psychomotor test over four sessions held at 10-hour intervals. Each participant was assigned a "constant routine." Participants were kept awake in a prone position within a room whose environment was held strictly constant (light, noise, temperature, meals, etc.). This control procedure provided assurance that any variation in participant performance was solely caused by sleep deprivation. The random generation task, nearly two minutes in length, consisted in verbally producing a sequence of 100 letters in a random fashion (i.e. by inhibiting, for example, alphabetical order) and by keeping to a set rhythm. Our assumption was that capacity for inhibition diminished as the number of hours of sleep deprivation increased. The simple reaction test, 10 minutes in length, involved pressing a button as swiftly as possible to cause a black square to disappear from a screen. In this case our assumption was that acute sleep deprivation alters simple reaction time. Analysis of variance (ANOVA) through repeated measures using the "sessions" factor as an intra-subject variable showed no significant changes in randomization indices of the random generation task, contrary to analysis of average simple reaction times. Participants' reaction times deteriorated over the first two minutes of the test during the night they were deprived of sleep. It would seem that the contradictory results of previous studies of the effects of acute sleep deprivation on the inhibition function would be due to errors in factor identification. In conclusion, the inhibition function, as measured during the performance of a brief task, seems to remain intact during an extended, 36-hour waking period. Simple reaction time assessed by means of a brief psychomotor test is affected during a night of sleep deprivation. The working-memory inhibition executive function shows greater resistance to acute sleep deprivation than does psychomotor reaction time for the performance of short tasks.     

Faith Development in the Lives of HIV-Positive Adults

Studies of religious faith consistently document the important role of religion in the lives of adults. Investigations of adult religious faith also suggest that a life crisis can stimulate faith development. However, these earlier studies do not explain how a life-threatening crisis changes adult religious faith. This study examines the impact of an HIV-positive diagnosis on adult religious faith development. Interviews were conducted with 18 HIV-positive men and women under 45 years of age. The researchers found that an HIV-positive diagnosis affects faith development in these ways: the perspective of faith shifts from a religious to a spiritual orientation for which the participants feel a stronger sense of ownership; the concept of God changes from an authoritarian to an empowering figure, and views of the self are transformed to include others.     

Neural Recruitment and CognitiveAging: Two Hemispheres Are Better Than One, Especially as You Age

Several neuroimaging studies have reported that older adults show weaker activations in some brain areas together with stronger activations in other areas, compared with younger adults performing the same task. This pattern may reflect neural recruitment that compensates for age-related neural declines. The recruitment hypothesis was tested in a visual laterality study that investigated age differences in the efficiency of bihemispheric processing. Letter-matching tasks of varying complexity were performed under two conditions: (a) matching letters projected to the same visual field (hemisphere) and (b) matching letters projected to opposite visual fields (hemispheres). As predicted by the recruitment hypothesis, older adults generally performed better in the bilateral than unilateral condition, whereas younger adults showed this pattern onlyfor the most complex task. We discuss the relation between these results and neuroimaging evidence for recruitment, and the relevance of the present bihemispheric advantage to other evidence for age-related changes in interhemispheric transfer.     

Family and Contextual Predictors of Depressive Symptoms in Inner-City African American Youth

Family and contextual predictors of depression in inner-city, African American youth have rarely been examined. In this study we explore the contribution of current and historical life events, family conflict, perceived social support from mother, maternal depression, and maternal explanatory style to the depressive symptoms of inner-city African American school-age (M = 10.7 years) children. Home interviews were conducted with 89 mother and child dyads living in moderate- to high-violent areas of a southeastern city. Regression analyses revealed that the children in this sample with higher levels of depressive symptoms had higher levels of child-reported everyday stress, were more likely to have been abused at some point in their past, came from homes with mothers who were less well educated, and had mothers who reported higher levels of depression, a past history of domestic abuse, as well as a less pessimistic explanatory style. Implications for interventions with inner-city African American families are discussed.     

Flanker recall and the flanker validity effect may reflect different attentional processes

High flanker recall in the correlated flanker task suggests a failure of selective attention. We used a dissociation approach to examine the role of attentional processing of the flankers’ identities in the flanker validity effect (FVE). In three experiments, flanker recall decreased as flanker duration decreased, but the FVE was not affected by flanker duration. Masking also produced a dissociation, in that masking decreased flanker recall but the FVE was not affected. Examination of on-line flanker identification suggested that flanker recall was an adequate measure of attentional processing of the flankers’ identities on most trials. The results suggest that attentional processing of the flankers’ identities is not related to the magnitude of the FVE and is not necessary for it to obtain. Because there is a failure of selective attention, the dissociations suggest that flanker recall and the FVE may reflect different attentional processes.     

Size-arrival effects: The potential roles of conflicts between monocular and binocular time-to-contact information, and of computer aliasing

With computer simulations of self-motion, participants approached a floating object and tried to “jump” over it without collision. Participants “jumped” significantly later over small objects than they did over larger objects. This occurred when the displays were viewed monocularly or binocularly, a finding that suggests that such size-arrival effects (DeLucia & Warren, 1994) were not due to a conflict between monocular and binocular cues to time-to-contact (TTC) information (Tresilian, 1994,1995). Moreover, the results further suggest that size-arrival effects are not due to irregularities in TTC information that can occur from computer abasing and that the latter does not always affect TTC estimation; visual information used in such judgments does not seem to be extracted on a frame-by-frame basis.     

Mother Knows Best? Mother and Child Report of Behavioral Difficulties of Children of HIV-Infected Mothers

Children of HIV-infected mothers have more psychosocial adjustment difficulties than do those of noninfected mothers. In this study, child psychosocial adjustment in children of HIV-infected women is examined across the three stages of HIV-infected: asymptomatic, symptomatic and AIDS. Participants were 99 HIV-infected women and 148 noninfected women. Children were not identified as being HIV infected. Mother and child reports of behavioral difficulties are compared, and competing hypotheses about mother report of child behavior difficulties are tested. Results indicate an ascending linear trend for child report of internalizing and externalizing difficulties from the noninfected stage through increasingly severe stages of HIV-infection. According to mother report, child externalizing and internalizing difficulties are nonlinear, as mothers report an increase through the infected symptomatic stage, then a decrease in the AIDS stage. Implications for assessment, prevention and intervention in families with maternal HIV infection are discussed.     

Multicultural Counseling Competencies as Tools to Address Oppression and Racism

The Multicultural Counseling Competencies (Arredondo et al., 1996; Sue, Arredondo, & McDavis, 1992) provide developmental and evaluative guidelines for enhancing counselor education and practice. A reason for the articulation of the competencies was the need to address racism and other forms of interpersonal and institutional oppression in the profession. The Dimensions of Personal Identity Model is discussed as a reference point to recognize various personal criteria that are often the focal point of discriminatory behavior. Specific competencies and explanatory statements provide checkpoints that address racism and other forms of oppression that are part of the human experience, but more particularly so for people of color in the United States.