Hippocampal synaptic plasticity during instrumental learning

present research examined the role of hippocampal NMDA-dependent synaptic potentiation on appetitive instrumental conditioning under a continuous reinforcement schedule. In the first experiment, low (.025 mg.kg) or moderate (.05 mg/kg) dosages of the NMDA receptor antagonist, MK801, failed to increase the number of training days required to reach acquisition criterion; number of training days required to reach criterion for extinction were also unaffected. In the second experiment, a higher dosage (.10 mg/kg) of MK801 or induction of long-term potentiation failed to alter the number of responses occurring during acquisition. These data suggest that hippocampal synaptic potentiation does not play a prominent role in instrumental learning with simple contingency conditions. It is suggested that hippocampal LTP reflects a perceptual process that contributes differentially to spatial cognition, classical and instrumental conditioning.     

THE CREDIBLE SHRINKING ROOM:

Abstract— Becoming a proficient symbol user is a universal developmental last in the first years of life, but delecting and mentally representing symbolic relations can be quite challenging for young children To test the extent to which symbolic reasoning per se is problematic, we compared the performance of 2-year-olds in symbolic and nonsymbolic versions of a search task. The children had to use their knowledge of the location of a toy hidden in a room to draw an inference about where to find a miniature toy in a scale model of the room (and vice versa) Children in the nonsymbolic condition believed a shrinking machine had caused the room to become the model They were much more successful than children in the symbolic condition, for whom the model served as a symbol of the room The symbol understanding and use.     

Book reviews

Enlightenment East and West Leonard Angel, 1994 Albany, State University of New York Press 388 pp.

Visions of Power: Imagining Medieval Japanese Buddhism Bernard Faure, trans, by Phyius Brooks, 1996 Princeton, Princeton University Press 329 pp.

Pāli Buddhism. Curzon Studies in Asian Philosophy Frank J. Hoffman & Deegaixe Mahinda (Eds), 1996 Richmond, Curzon Press xiii + 233 pp., ISBN 0 7007 0359 4, hb £40

Friendship East and West: philosophical perspectives Oliver Leaman (Ed.), 1996 Richmond UK, Curzon Press ix + 288 pp., ISBN 0 7007 0358 6, hb £40

Heidegger's Hidden Sources: East Asian Influences on his work Reinhard May, trans, by GRAHAM PARKES, 1996 London, Routledge xviii+ 121 pp., hb £35.00, pb £11.99

The Social Self in Zen and American Pragmatism Steve Odin, 1996 Albany, SUNY Press xvi + 482 pp., ISBN 0 9714 2492 8, pb $24.95

The Art of living. Aesthetics of the Ordinary in World Spiritual Traditions Crispin Sartwell, 1995 Albany, State University of New York Press xiv+ 163 pp., hb

East‐West Encounters in Philosophy and Religion Ninian Smart & B. Srinivasa Murthy (Eds), 1997 London, Sangam Books xxiii + 411 pp., ISBN 0 8613 2375 0, hb £24.95

Confucianism and Christianity: a comparative study of Jen and Agape Xinzhong Yao, 1996 Brighton, Sussex Academic Press viii+ 164 pp., ISBN 1 8987 2325 7, hb £35 and $55     

Assisting At-Risk College Students With Attributional Retraining and Effective Teaching1

Attributional retraining appears to be an effective remedial intervention for college students. However, the potential moderating effects of student and classroom characteristics have not yet been investigated systematically. In two studies, attributional retraining was provided to low- and high-risk students, followed by a videotaped lecture presented by either an ineffective or effective instructor. Attributional retraining enhanced achievement on a lecture-based achievement test only when combined with effective teaching, improving the achievement of students who had previously performed poorly (Experiment l), and of low-achieving externals (Experiment 2). The intervention provided no advantage for previously successful students and low-achieving internals. Moreover, attributional retraining induced a more internal attribution profile in students with an external locus, and increased expectations of future success in both externals and internals, but again only when students also received effective instruction. These results suggest that contextual factors related to the classroom, such as quality of instruction, and individual differences have to be considered when developing attributional retraining programs.     

CONTRIBUTIONS OF TIPLER'S OMEGA POINT THEORY

Abstract. An attempt to discover what can be learned from the recent work of Frank Tipler on the Omega Point theory requires an analysis of his framework of understanding from scientific, philosophical, and theological perspectives. A critique of his crucial ideas, and of the salient points raised by some of his critics, can then be undertaken within the compass of his strengths. A critique of the critiques of Tipler's work allows one to evaluate the extent and limitations of his contributions.     

On the Nature of Embarrassabllity: Shyness, Social Evaluation, and Social Skill

In this study, the correlates of embarrassability, or chronic susceptibility to embarrassment, were examined. Competing theoretical models suggest either that embarrassable people should be especially concerned about others' evaluations of them or that they should lack social skills. Further, shyness and embarrassment are typically considered to be closely related states. To test these propositions, 310 participants provided extensive self-reports of social skill, fear of negative evaluation, self-esteem, self-consciousness, and negative affectivity. Regression and factor analyses indicated that, compared to those of low embarrassability, highly embarrassable people are particularly concerned with the normative appropriateness of behavior and are more motivated to avoid rejection from others. In contrast, shyness was best predicted by low social self-confidence and low social skill. The data best support a social-evaluation model of embarrassment and argue that embarrassability is linked to the appropriateness of social behavior, and shyness to its effectiveness.     

Are All Hostility Scales Alike? Factor Structure and Covariation Among Measures of Hostility1

Few studies have examined the correlational and structural relationships between measures of hostility that may predict coronary heart disease. Using data from a population-based study (N= 2,682), we examined the factor structure among the five subscales from Siegel's (1986) Multi-dimensional Anger Inventory, the three subscales from Spielberger et al.'s (1985) anger expression scales, a Cook-Medley (Cook & Madley, 1954) hostility subscale that measures cynicism, and items measuring hostility from four scales that assess Type A behavior. Eight separate factors were identified: hostile anger expression, perceived control over the expression of one's anger, frequency of anger, ease of anger provocation, brooding, hostile outlook, cynicism, and sullenness. These results suggest that the structure of hostility measures is more complex than previous factor analyses have suggested. Our findings point to the dangers in assuming that a factor structure can be generalized beyond the data on which it is based to provide theoretical statements about psychological structure. The new scales appear to be valid because they correlate with demographic variables and indicators of social support in the expected directions.     

Behavioral Intentions: Which Ones Predict Fertility Behavior in Married Couples?1

The published literature on the relationship between behavioral intentions and fertility behavior exhibits four major problems: inconsistent and confusing use of theoretical constructs, limited use of different types of intentions, use of nonbehavioral outcomes, and failure to explore adequately the couple aspects of the intentions/behavior relationship. The study reported here addresses these problems by using a theoretical framework that characterizes the psychological/behavioral sequence leading to a planned conception, three different types of fertility intentions, a behavioral outcome variable, and data from 196 married couples with no children and 185 married couples with one child. Data analysis results in a simultaneous equation, constrained regression model which indicates that child-timing intentions are the most important predictors of proceptive behavior over a 3-1/2 year period and that childbearing intentions are next in importance; that behavioral intentions are the final common pathway through which fertility motivations, attitudes, beliefs, and desires affect behavior; that the use of proceptive behavior as an outcome variable improves the explanatory power of our models; and that the interaction of couple intentions do not demonstrate greater husband or wife influence over couple proceptive behavior but do demonstrate that disagreement has a delaying effect on the onset of that behavior.     

DOUBLE DISSOCIATION BETWEEN MEMORY SYSTEMS UNDERLYING EXPLICIT AND IMPLICIT MEMORY IN THE HUMAN BRAIN

Abstract— Amnesic patients have impaired explicit memory that is evident in poor recall and recognition of words, yet can have intact implicit memory for words as measured by repetition priming, the enhanced efficiency for reprocessing those word's. The dissociation between explicit and implicit memory for words is a fundamental characteristic of normal cognition that could reflect two different functional architectures of the human brain two separate processing systems or two levels of operation of a single system with implicit memory less demanding of that system. We present a patient who has a lesion in the right occipital lobe and who showed intact explicit and impaired implicit memory for words. The deficit was specific to visual priming. The double dissociation between explicit and implicit visual memory for words indicates that separate processing systems mediate these two forms of memory, and that a memory system in right occipital cortex mediates implicit visual memory for words.     

Bit-plane layering for high-resolution EGA and VGA graphics on the IBM PC/XT/AT

Each page of video memory comprises four parallel planes that can be manipulated and displayed independently or in combination. A technique is described that involves programming the video hardware to achieve this. The utility of well-known video programming technology, such as the tachistoscope display, is thereby extended. Assembly language code is included, and a demonstration program is described.