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.     

Ethnic identity, self-esteem, and ethnocentrism: a study of social identity versus multicultural theory of development

Social identity theory (SIT) proposes that the more strongly individuals identify with their group, the less favorable attitudes they hold toward dissimilar groups. In contrast, multicultural theory proposes that affirmation toward one's group--particularly with respect to ethnicity--should correspond with higher levels of acceptance toward dissimilar groups. These competing theories were examined with 486 non-Hispanic White, African American, and Hispanic/Latino university students to determine if support would be found for either theory. Consistent with SIT, levels of ethnic identity correlated significantly with levels of ethnocentrism for Whites and Hispanics but not for African Americans. African Americans obtained significantly higher ethnic identity and self-esteem scores than the other 2 groups. Implications of the findings are discussed.     

How conscious experience and working memory interact

Active components of classical working memory are conscious, but traditional theory does not account for this fact. Global Workspace theory suggests that consciousness is needed to recruit unconscious specialized networks that carry out detailed working memory functions. The IDA model provides a fine-grained analysis of this process, specifically of two classical working-memory tasks, verbal rehearsal and the utilization of a visual image. In the process, new light is shed on the interactions between conscious and unconscious aspects of working memory.     

Morally Relevant Features

This article summarizes the account of morality presented in Morality: Its Nature and Justification (Oxford, 1998), with emphasis on that aspect of morality that deals with justifying violations of the moral rules. Such justification requires a two-step procedure; the first is describing the situation using only morally relevant features. I list these features, noting how diverse they are, and describe their characteristics. The second step is estimating the consequences of publicly allowing a violation with the same morally relevant features, that is, allowing a violation when everyone knows that it is allowed to violate the rule in the same circumstances, and comparing this to the estimated consequences of not publicly allowing that kind of violation. I then explain why fully informed, impartial rational persons can sometimes disagree about whether a violation should be publicly allowed and note that such weakly justified violations are the controversial cases.     

Keeping Up with the Cloneses -- Issues in Human Cloning

The advent of cloning animals has created a maelstrom of social concern about the ethical issues associated with the possibility of cloning humans. When the ethical concerns are clearly examined, however, many of them turn out to be less matters of rational ethics than knee-jerk emotion, religious bias, or fear of that which is not understood. Three categories of real and spurious ethical concerns are presented and discussed: 1) that cloning is intrinsically wrong, 2) that cloning must lead to bad consequences, and 3) that cloning harms the organism generated. The need for a rational ethical framework for discussing biotechnological advances is presented and defended.     

In these pages . . .

The American Journal of Psychoanalysis -     

College Students’ Perceptions of Peers Who Cheat1

Two studies investigated the efficacy of 3 theoretical models in explaining college students judgments of peers who cheat and of accomplices who assist cheaters. The value pluralism model predicted that accomplices who acted for money would be judged more harshly than those who acted from friendship; the attributional model predicted that cheaters whose actions were caused by internal controllable factors would be judged more harshly than those who actions were caused by external uncontrollable factors, and the relative preference model predicted that students who saw themselves as more likely to act as the cheater and accomplice did would make less harsh judgments. Overall, the results provided the best support for the relative preference model.     

Trends in Telehealth versus On-site Clinical Genetics Appointments in Manitoba: A Comparative Study

Telehealth involves the use of information and communications technology to deliver health services to patients over distance. Canada is well suited to benefit from telehealth since many individuals live in remote, rural and isolated locations. Manitoba is the easternmost prairie province and MBTelehealth is an active Canadian program that currently has 105 sites in 73 communities. Although studies of patient satisfaction comparing telehealth to on-site clinical visits have been conducted, a comparative study of the types of genetics patients seen via these two modalities has not been performed previously. In this study we: (1) examined the uptake of telehealth in Genetics in Manitoba; (2) contrasted telehealth usage in Genetics with other clinical programs; and (3) performed a comparative study of the types of Genetics referrals seen in 2008 on-site versus via telehealth. Results indicate the uptake of telehealth is increasing and has made genetics outreach clinics unnecessary. The Program of Genetics and Metabolism is consistently one of the top ten utilizers of telehealth within the province. With respect to discipline, chi square analysis revealed the trends were not significantly different for on-site and telehealth encounters, with prenatal referrals being the most common and Hereditary Breast and Ovarian Cancer referrals being the least common. Referrals within each discipline varied depending on the need for fetal assessment and physical examination. Telehealth was utilized regularly for test results sessions across all disciplines.