Spatial working memory performance and fMRI activation interaction in abstinent adolescent marijuana users.

Previous studies have suggested neural disruption and reorganization in adult marijuana users. However, it remains unclear whether these effects persist in adolescents after 28 days of abstinence and, if they do, what Performance x Brain Response interactions occur. Adolescent marijuana users (n=17) and controls (n=17) aged 16-18 years were recruited from local schools. Functional magnetic resonance imaging data were collected after 28 days' monitored abstinence as participants performed a spatial working memory task. Marijuana users show Performance x Brain Response interactions in the bilateral temporal lobes, left anterior cingulate, left parahippocampal gyrus, and right thalamus (clusters >/=1358 microl; p<.05), although groups do not differ on behavioral measures of task performance. Marijuana users show differences in brain response to a spatial working memory task despite adequate performance, suggesting a different approach to the task via altered neural pathways.     

Evidence for executive deficits among users of MDMA (Ecstasy)

Random letter generation and computation span are tasks known to load on executive, prefrontal resources. Previous research suggests that Ecstasy users are impaired on random letter generation. The current study, employing a larger sample (44 current Ecstasy users, and 59 non‐Ecstasy users), together with more effective statistical controls for other drug use, failed to replicate previous findings. Ecstasy users were unimpaired on all measures of random generation performance. A significant difference was obtained on the computation span measure, with Ecstasy users scoring significantly lower than non‐Ecstasy users. This difference remained statistically significant following control for various indicators of the use of other drugs including cannabis. The results are discussed in terms of the potential effects that Ecstasy might have on different component executive processes.     

记忆中"曾经"的承诺

该文关注“曾经”与“承诺”—“复仇”与“拯救”如何相关特别是如何转换的“记忆的政治”。问题的背景是苦难:作为存在论或现象着的生活世界的基本事实,它是人类唯一可以普遍面对神、面对政治的“救赎地”,而不是“弥撒”中可以流逝的将来时,或在“复仇”中永远走不出的过去时。这里重要的是记忆形式的时间结构发生了根本的变化。因而“曾经”不是无生命力的过去压力(如尼采所批判的和本雅明所清理的);也不是简单转化为复仇的有生命力的权力意志即强权政治(如尼采所一厢情愿的);而是走出复仇的拯救———即走出过去时的———“记忆”中的“曾经”的“承诺”。但事实上,它已不能由西方文化的特质独立承担了。     

Color discrimination under chronic hypoxic conditions (simulated climb "Everest-Comex 97")

Hypoxia is known to alter visual functions. In the present study, the effects of chronic hypobaric hypoxia upon visual color discrimination were studied in 8 subjects participating in a simulated climb from sea level (PO2 = 210 hPa) to 8,848 m (PO2 = 70 hPa) over a 31-day period of confinement in a decompression chamber ('Everst-Comex 97'). During these investigations, the subjects were required to discriminate between colors of different hue in the red, blue, and green ranges. Alterations in color discrimination increased slightly but significantly as altitude increased. Impairments occurred mainly in the red and blue ranges. In addition, our results further indicate that color discrimination would be affected only when a minimum threshold of difference between color stimuli is not present. Methodological and physiological implications are discussed.     

Science,commonsense and philosophy: A defense of continuity (a critique of "network apriorism")

A popular line in philosophy championed by Jackson and his followers analyses concepts as networks of propositions. It takes even network-propositions characterizing ordinary empirically applicable concepts to be a priori, in contrast to statements of empirical science. This is meant to guarantee both the autonomy of conceptual analysis, and its substantial and informative character. It is argued here, to the contrary, that empirically applicable and entrenched concepts owe the acceptability of their own network precisely to its empirical pedigree. Promoting an empirical proposition into a network proposition does not make it ultimately a priori: no matter how entrenched the network is, it owes its ultimate justification to its empirical pedigree. Autonomy from experience and informativeness clash with each other: the stipulative "knowledge" is a priori in a weak sense, but not informative and substantial, the factual knowledge is substantial but not a priori .     

Memory anxiety and memory performance in adulthood

The present study examined the contribution of general and domain-specific anxiety to the prediction of memory performance in a sample of 350 young, middle-aged and old adults. In a preliminary stage of this investigation, psychometric analyses revealed that the predictive validity of the Anxiety scale of the Metamemory in Adulthood questionnaire, used to assess memory-related anxiety, could be improved by using an abbreviated version of the scale. This Memory Anxiety subscale predicted level of state anxiety experienced by middle-aged and older subjects in anticipation of a memory-demanding task. It was superior to the general state measures in predicting actual memory performance, but only for the oldest age group. Results thus provide support for domain- and age-specificity in the assessment of anxiety performance relationships.     

Memory development in adolescence: Relationships between metamemory,strategy use,and performance

Eighth and tenth grade students were asked to study and recall a list of paired associates. The word pairs were available either throughout an 8 sec per word study period or only at the beginning and were composed of either high frequency or low frequency words. After recall, students were asked to indicate which of several study strategies they had used with each word pair (read pair carefully, rehearsal, visual elaboration, verbal elaboration). In addition, they were asked which of these strategies would have had the best effect on recall. Knowledge of appropriate memory strategies (metamemory) was positively related to strategy use, and strategy use was positively related to recall performance at both ages. Improved performance with materials available throughout study and with high frequency word pairs was explained by increased use of elaborative strategies. Age differences in performance were explained by increased strategy effectiveness. These results are discussed in relation to changing relationships among metamemory, strategy use, and performance with age.     

Memory performance awareness in younger and older adults

Reports on the course of memory-monitoring skills across adulthood are discrepant in conclusions and limited in scope. The purpose of this study was to build a large data base (3 samples and 7 different tasks) to assess performance awareness. Younger (19-41 years) and older (59-93 years) Ss estimated performance either before (i.e., predictions) or after (i.e., postdictions) completing each task. Predictions were less accurate than postdictions at both age levels, suggesting Ss monitored performance during the study-test cycle. Overall, the data suggested no consistent age effects in performance awareness: Age differences in monitoring occurred only in predictions and only for some tasks. Between-tasks differences in age effects could not be attributed to a single mediating mechanism like those suggested in previous reports. Why previous research has produced conflicting conclusions about metacognitive development in adulthood is discussed in light of these data.     

Comparison of delay discounting of different outcomes in cigarette smokers,smokeless tobacco users,e-cigarette users,and non-tobacco users

Delay discounting is the process by which a commodity loses value as the delay to its receipt increases. Rapid discounting predicts various maladaptive behaviors including tobacco use. Typically, delay discounting of different outcomes has been compared between cigarette smokers and nonsmokers. To better understand the relationship of delay discounting to different modes of tobacco use, we examined the differences in delay discounting of different outcomes between cigarette smokers, smokeless tobacco users, e-cigarette users, and non-tobacco users. In the present study, all participants completed 8 titrating delay-discounting tasks: $100 gain, $500 gain, $500 loss, alcohol, entertainment, food, a temporary health gain, and a temporary cure from a disease. Non-tobacco users discounted most outcomes less than tobacco users overall; however, there were no differences in discounting among the different types of tobacco users. These results suggest that nicotine consumption of any kind is associated with a higher degree of impulsivity compared to non-tobacco users. Adoption of tobacco products that have been perceived as less harmful (e.g., e-cigarettes) is not associated with a baseline difference or decrease in delay discounting if adopted after a history of cigarette use.     

Memory complaint and memory performance in the depressed elderly

Depressed and nondepressed elderly subjects recruited in the context of a large epidemiological study of health were compared on measures of self-reported memory disturbance and an objective index of memory performance (free recall). Three groups were studied including (a) subjects meeting Research Diagnostic Criteria (RDC) for major depression, (b) subjects with high levels of self-reported depressive symptoms who did not meet RDC for major depression, and (c) subjects with low levels of self-reported depressive symptoms. Subjects with high depression symptom levels reported significantly higher levels of memory complaint than did subjects with low symptom levels. However, there were no differences in self-reported memory disturbance as a function of depression diagnosis. Further, there were no significant differences between groups on the free-recall measure, either as a function of symptom level or diagnosis. It is argued that symptom severity rather than diagnosis of depression is important in determining impairment in depressed elderly people.     

Eye movements reveal no immediate "WOW" ("which one's weird") effect in autism spectrum disorder

Autism spectrum disorder (ASD) and typically developed (TD) adult participants viewed pairs of scenes for a simple "spot the difference" (STD) and a complex "which one's weird" (WOW) task. There were no group differences in the STD task. In the WOW task, the ASD group took longer to respond manually and to begin fixating the target "weird" region. Additionally, as indexed by the first-fixation duration into the target region, the ASD group failed to "pick up" immediately on what was "weird". The findings are discussed with reference to the complex information processing theory of ASD (Minshew & Goldstein, 1998 ).     

Comment on "Memory storage and retrieval processes in category learning"

This article is based on the Estes (1986b) article that examined learning processes associated with categorization in relation to new-old recognition. The focus of the commentary is on alternative views of recognition/classification relations as well as the implications of the more detailed analyses of learning for exemplar-based classification models. The argument is made that strategies typically used by experimental participants and exemplar processing have some fundamental properties in common. This implies that a good fit to classification data by an exemplar model does not necessarily mean that performance is based on comparisons with remembered exemplars but suggests that abstract representations may not be different kinds of entities from the memory representation of a specific experience.     

Eroticism in group psychotherapy: psychoanalytic reflections on desire, agony, and ecstasy

To fully understand the complexities of eroticism in groups, it may be necessary to review a conceptual differentiation of desire and its allies: agony and ecstasy. This article suggests that psychoanalytic group psychotherapy is made for neither agony nor ecstasy. Sexual excitement maybe; eroticism and desire, yes; agony and ecstasy, no. While agony or ecstasy imply a threat to the survival of the group, eroticism and desire reaffirm its existence. In this manner the group may be converted into a theater where desire may be celebrated, while the threat of being dissolved in the depths or exaltation of agony and ecstasy is elaborated and worked through: "Desire is desire only if it succeeds in postponing something".     

权利、法律与犯罪:“属人”的还是“为我”的?——《德意志意识形态》中《我的权力》部分解读

目前马克思主义政治哲学研究中,对经典作家原始文本及其思想的深度挖掘和客观阐释仍显得非常不够,基于此,本文特别解读了《德意志意识形态》中选择关乎这一议题的《我的权力》部分。在人们通常的理解中,权利、法律乃至犯罪等现象归属具体法学讨论的范畴,然而无论是施蒂纳还是马克思、恩格斯,从来没有把它们看作单纯的法的问题,而是从个体与社会的分野中,紧密结合人的自由问题来透视它们的存在方式、表现形态及其本质特征,这使其各自的分析别具特色和深度,而且呈现出两种很不相同的视角和思路。当然,它们之间与其说是对立的,还不如说是互补的;人的社会性与个体性的矛盾、现实性与超越性的差异,要求我们必须多角度、多方位地考虑问题、判明趋势,这也符合马克思主义的辩证分析方法。     

The "don't ask, don't tell" policy and military performance

This paper is a response to Schumm's 2004 critique of Belkin's 2003 article, dealing with the "Don't Ask, Don't Tell" policy in the U.S. military. Schumm's critique specified four reasons for continuing to exclude homosexuals from military service: military effectiveness, sexual asymmetries, Christian soldiers' dilemma of "living a lie" and skewed opinions of policy makers and military elites. Each of these categories is analyzed and discussed.     

Interviewing intoxicated witnesses: Memory performance in theory and practice

Memory encoding and recall involving complex, effortful cognitive processes are impaired by alcohol primarily due to impairment of a select few, but crucial, cortical areas. This review shows how alcohol affects some, but not all, aspects of eyewitnesses' oral free recall performance. The principal results, so far, are that: a) free recall reports by intoxicated witnesses (at the investigated BAC‐levels) may contain less, but as accurate, information as reports by sober witnesses; b) immediate reports given by intoxicated witnesses may yield more information compared to reports by sober witnesses given after a one week delay; c) an immediate interview may enhance both intoxicated and sober witnesses' ability to report information in a later interview; and d) reminiscence seems to occur over repeated interviews and the new information seems to be as accurate as the previously reported information. Based on this, recommendations are given for future research to enhance understanding of the multifaceted impact of alcohol on witnesses' oral free recall of violent crimes.     

The influence of "preparedness" on autoshaping, schedule performance, and choice.

Two groups of experimentally naive pigeons were exposed to an autoshaping procedure in which the response key was mounted on the wall (the conventional location) or on the floor of the chamber. In two experiments, subjects readily responded to the wall key, but floor-key subjects required shaping. A subsequent experiment compared performance of wall- and floor-key groups on an ascending series of fixed-ratio schedule values, resistance to extinction, differential reinforcement of other behavior, and reversal of key assignment. Each experiment was followed by several sessions of fixed-ratio training; the performance of the wall- and floor-key groups was almost identical throughout. In the final experiment, a fixed-ratio requirement could be completed on either or both keys. Birds initially chose the key on which they had responded during the preceding (reversal of key assignment) experiment. However, within a few sessions both groups showed almost exclusive preference for the floor key. Preference for a key located on the floor may follow from the fact that pigeons are ground feeders and may thus be more "prepared" to peck the floor than to peck a wall. However, autoshaping, under the conditions prevailing here, occurred much more readily to the wall key, suggesting that pecking a vertical surface is more highly prepared. Difficulties in determining relative preparedness seem moot, however, given the lack of between-group differences in the intervening experiments. It is thus unlikely that schedule performances critically depend upon the specific operant response involved.     

Memory Span,Naming Speed,and Memory Strategies in Poor and Normal Readers

Eleven-year-old severely impaired poor readers failed to show a word length effect with pictorial presentation, but showed an effect of equal magnitude to that of reading age and chronological age controls with auditory presentation. The lack of a pictorial word length effect was unlikely to be due to slow speed of naming skills, as in one study these were at least as fast as those of the reading age controls. It is possible that the poor readers failed to verbally encode the pictures. However, they reported using verbal rehearsal, and lip movements were often observed during presentation, suggesting that they did verbally encode the items. Therefore they may have failed to show a word length effect because they did not retrieve information from the phonological store at recall. Although the poor readers had impaired naming speed skills for their age on both discrete item identification and articulation rate tasks, they could not be equated with their chronological age controls on memory span or reading when these naming speed differences were controlled. However, the groups were matched on the naming speed measures when differences in reading ability were controlled.     

Memory load as a cognitive antidote to performance decrements in data entry

In two experiments, subjects trained in data entry, typing one 4-digit number at a time. At training, subjects either typed the numbers immediately after they appeared (immediate) or typed the previous number from memory while viewing the next number (delayed). In Experiment 2 stimulus presentation time was limited and either nothing or a space (gap) was inserted between the second and third digits. In both experiments after training, all subjects completed a test with no gap and typed numbers immediately. Training with a memory load improved speed across training blocks (Experiment 1) and eliminated the decline in accuracy across training blocks (Experiment 2), thus serving as a cognitive antidote to performance decrements. An analysis of each keystroke revealed different underlying processes and strategies for the two training conditions, including when encoding took place. Chunking (in which the first and last two digits are treated separately) was more evident in the immediate than in the delayed condition and was exaggerated with a gap, even at test when there was no gap. These results suggest that such two-digit chunking is due to stimulus encoding and motor planning processes as well as memory, and those processes transferred from training to testing.