bluuebunny/crossref_metadata_2025 huggingface dataset:
The Role of Horizontal Connections in Generating Long Receptive Fields in the Cat Visual Cortex
Authors: Bolz Jürgen , Gilbert Charles D.
Published: April 2006

The cells in the primary visual cortex possess numerous functional properties that are more complex and varied than those seen in the cortical input. These properties result from the network of intrinsic cortical connections running across the cortical layers and between cortical columns. In the current study we relate the long receptive fields that are characteristic of layer 6 cells to the input that these cells receive from layer 5. The axons of layer 5 pyramidal cells project over long distances within layer 6, enabling layer 6 cells to collect input from regions of cortex representing large parts of the visual field. When layer 5 was locally inactivated by injection of the inhibitory transmitter GABA, layer 6 cells lost sensitivity over the portion of their receptive fields corresponding to the inactivated region of layer 5. This suggests that the extensive convergence in the projection from layer 5 to layer 6 is responsible for generating the long receptive fields characteristic of the layer 6 cells.
Postnatal Development of Protein Kinase C‐like Immunoreactivity in the Cat Visual Cortex
Authors: Stichel Christine C. , Singer Wolf
Published: April 2006

The postnatal development of protein kinase C isozymes II and III (PkCII/III) was investigted in the cat visual cortex by applying immunohistochemical methods with a monoclonal antibody against PkC(II/III).

PkC(II/III)‐like immunoreactivity was found in astrocytes and neurons. All astrocytes but only a few of the immunoreactive neurons were homogeneously labelled. The majority of the latter exhibited a punctate distribution of reaction product. The staining pattern of neurons and glial cells showed developmental changes until at least 18 months of age. These were characterized by (1) a gradual increase of immunolabelled astrocytes, (2) an abrupt appearance of immunopositive neurons at 4 weeks of age, (3) an aggregation of immunolabelled neurons in a well‐delineated band in lower layer IV between 4 weeks and 12 months of age, and (4) a decrease in number of PkC(II/III)‐positive neurons after 12 months of age.

These developmental changes in the expression of PkC(II/III)‐like immunoreactivity correlate well with the time course and the laminar selectivity of experience‐dependent malleability. Moreover, they correspond closely to changes in several systems that contribute to PkC‐activation and are thought to be involved in use‐dependent neuronal plasticity. Thus, we consider these results as compatible with the hypothesis that the PkC isozymes II and III participate in cellular mechanisms underlying use‐dependent plasticity.
Efferent Projections to the Host Brain from Intrastriatal Striatal Mouse‐to‐rat Grafts: Time Course and Tissue‐type Specificity as Revealed by a Mouse Specific Neuronal Marker
Authors: Wictorin K. , Lagenaur C. F. , Lund R. D. , Björklund A.
Published: April 2006

The developmental time‐course and growth characteristics of efferent graft‐to‐host projections were studied from mouse fetal striatal grafts (E13–14) implanted as a cell suspension into the ibotenate‐lesioned striatum of immunosuppressed adult rats. A cell surface monoclonal antibody specific for mouse neurons (M6) was used to identify the donor cells and their projections into the host brain. At 3–5 days after implantation, sparse fascicles of M6‐positive graft‐derived fibres extended for ∼0.3–0.4 mm across the graft‐host border into the surrounding host striatum. From the beginning they were selectively orientated in one direction, i.e. caudally along the myelinated fibre bundles of the internal capsule. At 8 days, the graft‐derived fibres were more numerous and more densely labelled. They ran in dense fascicles inside the myelinated bundles of the host internal capsule and reached the rostral host globus pallidus, a distance of ∼ 1.2 mm from the caudal tip of the graft. Two weeks after grafting, the M6‐positive fibre fascicles were clearly seen to branch within the globus pallidus to form terminal‐like networks. From this time onwards, the immunoreactivity of the outgrowing fibre fascicles gradually diminished, although small but dense terminal‐like networks could be found in the host globus pallidus in most, but not all, of the rats at longer survival times (3–15 weeks). This is consistent with previous work showing that outgrowing axons lose their M6 immunoreactivity as they mature and become myelinated. Control grafts of fetal neocortical and fetal cerebellar tissue were used to assess the tissue‐type specificity of the efferent fibre growth. The neocortical implants projected densely up to about 3 mm into the host brain, along the internal capsule and the corpus callosum and into the overlying cortex. By contrast, although the cerebellar grafts survived well, they showed very little efferent fibre growth. Double immunostaining for DARPP‐32 and M6 revealed that all M6‐positive fibre fascicles extending from the striatal (but not neocortical) grafts also showed DARPP‐32 positivity, and thus that it was the DARPP‐32‐positive regions of the striatal grafts that projected to the host brain. It is concluded that graft‐to‐host projections, running along and inside host myelinated bundles, are formed from intrastriatal striatal grafts within 1–2 weeks of implantation. Grafts of neocortical tissue grew well along the same trajectory, whereas neurons of a type not normally projecting along the internal capsule, i.e. cerebellum, failed to extend axons over any significant distance along this trajectory.
Two Promoters Direct Transcription of the Mouse NT‐3 Gene
Authors: Leingärtner Axel , Lindholm Dan
Published: April 2006

The structure of the mouse neurotrophin‐3 (NT‐3) gene has been analysed using genomic cloning and the rapid amplification of cDNA ends (RACE) method. The gene consists of two small upstream exons (exons IA and IB) and a larger downstream exon (exon II) that encodes the mature protein. Two classes of NT‐3 transcripts, termed transcripts A and B, are generated by alternative splicing of exon IA or exon IB to the common exon II. The NT‐3 gene also contains several transcription start sites in both upstream exons, and three different polyadenylation sites in exon II, as shown by RNase protection assays and by RACE, giving rise to multiple NT‐3 mRNA variants of slightly different lengths. Cerebellar granule neurons express both classes of NT‐3 transcripts, but only transcript B is regulated by tri‐iodothyronine (T3) in these neurons. The effect of T3 on NT‐3 mRNA is primarily due to transcription enhancement, as shown in nuclear run‐on experiments. The levels of NT‐3 mRNA are much lower in cultured mouse astrocytes and are undetectable in the human neuroblastoma cell line IMR 32. A TATA box is present in the upstream region of exon IB but not in that of exon IA. Promoter analysis using the chloramphenicol acetyltransferase reporter gene fused to different NT‐3 upstream regions showed the presence of two active NT‐3 promoters in cerebellar granule neurons. However, in IMR 32 cells, NT‐3 promoter activity decreased dramatically with increasing length of the 5′ flanking region. This suggests that expression of the NT‐3 gene is regulated both by positive influences, such as T3, and by negative silencing elements present in the upstream regions of the NT‐3 promoter.
Cellular and Subcellular Distribution of NMDAR1 Splice Variant mRNA in the Rat Lumbar Spinal Cord
Authors: Tölle T. R. , Berthele A. , Laurie D. J. , Seeburg P. H. , Zieglgänsberger W.
Published: April 2006

The regional distribution of alternatively spliced messenger RNA encoding the N‐methyl‐D‐aspartate (NMDA) receptor R1 subunit (NMDAR1) variants was examined by in situ hybridization in the rat lumbar spinal cord. Splice‐specific oligonucleotide probes [recognizing full‐length mRNA (NMDAR1‐1), deletion exon 21 (NMDAR1‐2), deletion exon 22 (NMDAR1‐3), combined deletion exons 21 and 22 (NMDAR1‐4) and mRNA which lacks (NMDAR1‐a) or contains exon 5 (NMDAR1‐b)] detected marked differences in abundance and distribution of N‐ and C‐terminal spliced variants. The NMDAR1‐a, NMDAR1‐2 and NMDAR1‐4 mRNAs were evenly distributed throughout all laminae of the dorsal and ventral horns. In the superficial dorsal horn NMDAR1‐b mRNA was preferentially detected in laminae II inner and III, while NMDAR1‐1 mRNA was restricted to laminae I to III. Large neurons in laminae IV and V contained mainly NMDAR1‐a, NMDAR1‐2 and NMDAR1‐4 mRNAs and occasionally NMDAR1‐b. The NMDAR1‐3 variant was only detected in very low abundance, being restricted to occasional cells in lamina I and II. In the ventral horn, motor neurons showed strong signals for NMDAR1‐a, NMDAR1‐b, NMDAR1‐2 and NMDAR1‐4 mRNAs. Serial sectioning through large motor neurons permitted the detection of multiple splice variants in single neurons. Analysis of the subcellular distribution of the mRNAs revealed that the NMDAR1‐1 mRNA was almost exclusively found in the cell nucleus, NMDAR1‐a mRNA was largely in the cytoplasm, while all other splice variants showed a homogeneous distribution between nucleus and cytoplasm. Comparison of the in situ hybridization images with functional analyses of heteromeric recombinant receptors will be necessary to ascertain whether splice variants of the NMDAR1 receptor subunit can account for some of the known electrophysiological properties of spinal cord neurons under physiological and pathophysiological conditions.
Expression of c‐Jun, Jun B, Jun D and cAMP Response Element Binding Protein by Schwann Cells and their Precursors In Vivo and In Vitro
Authors: Stewart Helen J. S.
Published: April 2006

In order to identify the transcription factors that may be involved in the development and differentiation of rat Schwann cells we examined the expression of c‐Jun, Jun B, Jun D and the cAMP response element binding protein (CREB) in vivo and in vitro. We found that CREB was expressed at high levels throughout nerve development by both Schwann cells and their precursors. Jun family members, on the other hand, were expressed only at low levels in a few nuclei of the developing nerve. After sciatic nerve transection, however, c‐Jun levels were rapidly up‐regulated in many Schwann cells of the distal stump but CREB, Jun B and Jun D levels were not affected. When nerve contact was resumed after crush injury c‐Jun levels returned to control values. Interestingly, unlike the situation in vivo, when Schwann cells were removed from the nerve and cultured, levels of all three Jun family members were rapidly up‐regulated. This also occurred in Schwann cell precursors. In other experiments we found that Schwann cell c‐Jun, but not Jun B or Jun D, expression was down‐regulated by the adenylate cyclase activator, forskolin. In addition, we show that the forskolin induced down‐regulation of c‐Jun is not necessary for Schwann cell proliferation or myelination to occur.
Preferential Growth of Neonatal Rat Dorsal Root Ganglion Cells on Homotypic Peripheral Nerve Substrates In Vitro
Authors: Anand Uma , McMahon Stephen B. , Cohen James
Published: April 2006

Developing sensory neurons interact with molecular signals in the local environment to generate stereotypic nerve pathways. Regenerating neurons seem to lose the ability to reinnervate their original sites in the targets, resulting in abnormal sensory input and consequent clinical pathophysiology. The specificity of reinnervation of peripheral targets by regenerating axons is thus crucial for normal recovery of function. In this study, we have examined evidence for selectivity of interactions between primary afferent neurons from identified levels of the spinal cord and different peripheral nerve environments by culturing these neurons on sections of nerves to muscle and viscera. We have compared the growth of a population of sensory afferents normally innervating somatic targets (dorsal root ganglion cells from L4 and L5) with populations containing many afferents innervating visceral targets (L6 and S1 dorsal root ganglia and nodose ganglion). These neurons, from newly born rats, were cultured on unfixed cryostat sections of normal and prelesioned gastrocnemius nerve, pelvic spinal nerve and vagus nerve from adult rats. Normal muscle nerve was seen to support the regeneration of a significantly greater proportion of somatic neurons, with longer neurites, than the visceral nerves. Similarly, much higher proportions of the‘visceral’population of afferent neurons were seen to extend neurites on the normal visceral nerve substrates, with longer neurites, than on the muscle nerve substrate. The selectivity displayed by the sensory neurons for their normal nerve substrates was abolished when they were cultured on prelesioned nerve substrates subjected to Wallerian degeneration, which was apparent from the equivalent and increased proportions of growing neurons having comparable neurite lengths, on all the nerve substrates. We conclude that sensory neurons recognize and respond to substrate‐specific and substrate‐bound molecules present in normal adult peripheral nerves, and that these differences are lost in prelesioned nerves following Wallerian degeneration.
Pain Processing in Four Regions of Human Cingulate Cortex Localized with Co‐registered PET and MR Imaging
Authors: Vogt Brent A. , Derbyshire Stuart , Jones Anthony K. P.
Published: April 2006

Neurosurgical and positron emission tomography (PET) human studies and animal electrophysiological studies show that part of the anterior cingulate cortex (ACC) is nociceptive. Since the contribution of the ACC to pain processing is poorly understood, this study employed PET and magnetic resonance (MR) image co‐registration in grouped and individual cases to locate regions of altered relative regional cerebral blood flow (rCBF). Seven right‐handed, neurologically intact males were subjects; each received neuropsychological and pain threshold testing. Subjects were scanned during infusion of H2[15O]: four randomized scans during innocuous heat stimulation to the back of the left hand and four scans during noxious but bearable heat to the same place. The averaged rCBF values during innocuous stimuli were subtracted from those during noxious stimuli and statistical parametric maps (SPMs) for the group were computed to identify regions of altered relative rCBF. Finally, single‐subject PET images of elevated and reduced rCBF were co‐registered with MR images and projected onto reconstructions of the medial surface of the hemisphere. The SPM analysis of the group showed one site with elevated rCBF in the midcingulate cortex and one in the perigenual cortex predominantly contralateral to the side of stimulation. There were bilateral sites of reduced rCBF in the cingulofrontal transitional cortex and in the posterior cingulate cortex (PCC). Co‐registered PET and MR images for individuals showed that only one case had a single, large region of elevated rCBF, while the others had a number of smaller regions. Six cases had at least one significant elevation of rCBF in the right hemisphere that primarily involved area 24b'; five of these cases also had an elevation in area 32′, while the seventh case had elevated rCBF in these areas in the left hemisphere. The rostral site of elevated rCBF in the group was at the border of areas 24/24’and areas 32/32′, although most cases had a site of elevation more rostral in the perigenual cingulate cortex. The ACC site of reduced rCBF was in areas 8 and 32 and that in the PCC included much of areas 29/30 in the callosal sulcus, areas 23b and 31 on the cingulate gyral surface and parietal area 7m. The localization of relative rCBF changes suggests different roles for the cingulate cortex in pain processing: (i) elevated rCBF in area 24’may be involved in response selection like nocifensive reflex inhibition; (ii) activation of the perigenual cortex may participate in affective responses to noxious stimuli like suffering associated with pain; and (iii) reduced rCBF in areas 8 and 32 may enhance pain perception in the perigenual cortex, while that in the PCC may disengage visually guided processes.
Global Traits: A Neo-Allportian Approach to Personality
Authors: Funder David C.
Published: April 2006

This paper outlines a theory of global traits based on the seminal writings of Gordon Allport and 50 years of subsequent empirical research. Personality research needs to refocus on global traits because such traits are an important part of everyday social discourse, because they embody a good deal of folk wisdom and common sense, because understanding and evaluating trait judgments can provide an important route toward the improvement of social judgment, and because global traits offer legitimate, if necessarily incomplete, explanations of behavior. A substantial body of evidence supporting the existence of global traits includes personality correlates of behavior, interjudge agreement in personality ratings, and the longitudinal stability of personality over time. Future research should clarify the origins of global traits, the dynamic mechanisms though which they influence behavior, and the behavioral cues through which they can most accurately be judged.
Optimal Movement Selection
Authors: Rosenbaum David A. , Slotta James D. , Vaughan Jonathan , Plamondon Réjean
Published: April 2006

Most physical tasks can be performed with an infinite number of movement patterns. How then are particular patterns selected? We propose that the contributions of individual limb segments depend on their own independently assessed fits to task demands. An advantage of this system is that coordination among limb segments can be achieved without explicit control of limb-segment interactions. In addition, the system allows segments that are still functioning to compensate for segments that are disabled. To test the model, we first asked subjects to oscillate the fingertip over varying distances at varying rates, using only the finger, hand, or forearm. Based on their performance, we identified the optimal amplitude and frequency of movement for each limb segment. Then we allowed the subjects to use the finger, hand, and forearm however they wished. We demonstrate that the relative contribution of each limb segment to fingertip displacement is predicted by the similarity of the optimal amplitude and frequency of that segment to the required amplitude and frequency of fingertip displacement. Because our model is similar to models proposed for learning and perception, common computational approaches appear viable for motor control and other more widely studied activities underlying information processing and behavior.
Degrees of Freedom in Behavior
Authors: Marken Richard S.
Published: April 2006

Coordinated behavior is typically explained in terms of motor programs or coordinative structures. The experiments described in this report suggest that a better explanation may be provided by control theory. In all experiments, subjects controlled the two-dimensional position of a cursor. By varying the disturbances to the two degrees of freedom of cursor movement, it was possible to elicit task-specific, unidimensional movement patterns resembling coordinative structures. Perturbation of one dimension of the movement pattern failed to produce a concomitant response in the other dimension unless there was a link between the degrees of freedom of action and perception. The subjects' behavior was accurately simulated by the behavior of independent feedback control systems. The results show that the problem of coordinating many degrees of freedom of action can be solved by viewing behavior as control of the perceptual consequences of these actions.
Individual Differences in Cellular Immune Response to Stress
Authors: Manuck Stephen B. , Cohen Sheldon , Rabin Bruce S. , Muldoon Matthew F. , Bachen Elizabeth A.
Published: April 2006

Correlational studies suggest that psychological stress suppresses cellular immune function in some, but not all, individuals. Here, effects of acute mental stress on lymphocyte subpopulations and T-lymphocyte mitogenesis were examined experimentally in healthy young adults. CD8 (T-suppressor/cytotoxic) lymphocytes increased in number and T-cell response to stimulation by phytohemagglutinin was attenuated following exposure to a 20-min laboratory stressor, but only in persons who also showed heightened catecholamine and cardiovascular reactions to stress. Hence, individuals differ substantially in their immunologic responsivity to behavioral stimuli, and such differences parallel (and may be predicted by) interindividual variability in stress-induced sympathetic nervous system activation.
Beyond Literal Meanings: The Psychology of Allusion
Authors: Glucksberg Sam
Published: April 2006

When people understand expressions that are intended nonliterally, two kinds of meaning are simultaneously apprehended: the literal meanings of the words themselves and the speaker's intended figurative meaning. Standard models of language comprehension assume that the literal meanings of figurative expressions are rejected in favor of a nonliteral meaning. I propose an alternative approach in which literal meanings are systematically used to convey figurative meanings through the process of allusion: The use of an expression to refer to entities or situations that are prototypical exemplars of culturally shared concepts and symbols. This approach provides an account of how people use and understand figurative language in general, and metaphor and idioms in particular.
Mental Chronometry: Beyond Reaction Time
Authors: Abrams Richard A. , Balota David A.
Published: April 2006

Details of response execution were examined in two classic human information processing paradigms: lexical decision and memory scanning. In the lexical decision experiment, word frequency influenced both the time of response onset and kinematic properties of the response. In the memory scanning experiment, when the probe was present in the memory set, the responses were both initiated sooner and were more forceful when the memory set consisted of two items than when it consisted of six items. When the probe was absent from the memory set, responses were initiated sooner but were less forceful when the memory set consisted of two items than when it consisted of six items. The results suggest that the amount of activation in support of a given response can modulate both the time taken to initiate the response and the force with which the response is executed. These findings bear on all models of human cognitive performance that have been developed within the mental chronometry tradition.
Associations between Cognitive Abilities and Scholastic Achievement: Genetic Overlap but Environmental Differences
Authors: Thompson Lee Anne , Detterman Douglas K. , Plomin Robert
Published: April 2006

Little is known about the genetic and environmental etiology of the association between specific cognitive abilities and scholastic achievement during the early school years. A multivariate genetic analysis of cognitive and achievement measures was conducted for 146 pairs of identical twins and 132 pairs of fraternal twins from 6 to 12 years of age. At the phenotypic level, measures of achievement were moderately correlated with specific cognitive abilities. A multivariate model including one general factor and specific factors in the genetic and environmental matrices indicated that the phenotypic relationship between achievement and cognition was mediated primarily by genetic influences. Genetic correlations among the cognitive and achievement tests ranged from .57 to .85, shared environment correlations were essentially zero, and specific environment correlations were low (.00 to .19). We conclude that there is substantial overlap between genetic effects on scholastic achievement and specific cognitive abilities. Performance on ability measures differs from that on achievement measures largely for environmental reasons.
Mediation of Adult Age Differences in Cognition by Reductions in Working Memory and Speed of Processing
Authors: Salthouse Timothy A.
Published: April 2006

Three studies, involving a total of 672 adults between 20 and 84 years of age, were conducted to evaluate the relative importance of working memory and perceptual comparison speed in the age-related differences in selected measures of cognitive functioning. The same measures of working memory and comparison speed were used in each study, but the studies differed in the specific cognitive measures examined. A common finding across all studies was that the magnitude of the age-related cognitive differences was greatly reduced by statistically controlling measures of working memory and perceptual comparison speed. Many of the age differences in process or fluid aspects of cognition therefore appear to be mediated by age-related reductions in working memory, which may in turn be largely mediated by age-related reductions in the speed of executing simple processing operations.
Hypothalamic Cooling Elicits Eating: Differential Effects on Motivation and Pleasure
Authors: Berridge Kent C. , Zajonc Robert B.
Published: April 2006

The perceived attractiveness of stimuli to humans has been modulated by changes in cephalic blood temperature. Can similar effects be produced in animals by manipulation of hypothalamic temperature? This study examined the attractiveness and pleasure of food to rats during hypothalamic cooling or hypothalamic heating, by measuring feeding and hedonic and aversive facial reactions to taste. Hypothalamic cooling administered through a permanently implanted thermode elicited feeding. Hypothalamic heating did not. Hedonic and aversive reactions to taste were unaltered by hypothalamic cooling or heating, even for rats that ate during cooling. Hypothalamic cooling may thus potentiate the attractive quality of food without modulating basic taste pleasure.
Ordinal Judgments of Numerical Symbols by Macaques (Macaca Mulatta)
Authors: Washburn David A. , Rumbaugh Duane M.
Published: April 2006

Two rhesus monkeys (Macaca mulatta) learned that the arabic numerals 0 through 9 represented corresponding quantities of food pellets. By manipulating a joystick, the monkeys were able to make a selection of paired numerals presented on a computer screen. Although the monkeys received a corresponding number of pellets even if the lesser of the two numerals was selected, they learned generally to choose the numeral of greatest value even when pellet delivery was made arrhythmic. In subsequent tests, they chose the numerals of greater value when presented in novel combinations or in random arrays of up to five numerals. Thus, the monkeys made ordinal judgments of numerical symbols in accordance with their absolute or relative values.
Leon Festinger and the Art of Audacity
Authors: Aronson Elliot
Published: April 2006

PS takes notice of the collected works of Leon Festinger and Donald T. Campbell—preeminent innovators of the methods and theory of modern social psychology
The Gene Chase in Behavioral Science
Authors: McClearn Gerald E. , Plomin Robert , Gora-Maslak Grazyna , Crabbe John C.
Published: April 2006

The study of genetic influence on behavior has featured two general approaches. The first is to search for a single gene with influence sufficiently great as to be detectable against almost any genetic or environmental background. The second general approach is to apply the statistical models of quantitative genetics that partition variance of a continuously distributed phenotype into various fractions, attributable to the actions of many genes of individually small effect, and to the influence of environment. Recent developments in molecular genetics have provided tools for exploring a middle ground of genetic influence: genes whose effects are not overwhelming, but which account for appreciable proportions of the variance. These quantitative trait loci (QTL) offer attractive prospects of bridging the gap between molecular and quantitative genetic perspectives.
Measurement of Stress: Scaling the Magnitudes of Life Changes
Authors: Birnbaum Michael H. , Sotoodeh Yass
Published: April 2006

This paper evaluates models and measurements of the stress induced by life changes to determine whether a single scale can explain several different phenomena, including judgments of “ratios” and “difference” as well as “combinations.” Judgments of “ratios” and “differences” were found to be approximately monotonically related, suggesting that these judgments should not be taken at face value, but instead that the same comparison operation governs both tasks. Judgments of “combinations” of stressful events were not simply the sums of their separate events; instead, they showed two systematic departures from additivity. First, the effect of a given event was less when it was the least stressful event in a combination than when it was the most, as if the most stressful event carries extra configural weight. Second, each additional stressor had diminishing marginal effect on the overall judgment. All three sets of data could be explained with a single scale using the theory that “ratios” and “differences” are both governed by subtraction and that “combination” judgments are a configurally weighted combination of the same scale values. This unified scale of stress seems preferable to the previous scale that was based on magnitude estimation.
The Relative Weighting of Position and Velocity in Satisfaction
Authors: Hsee Christopher K. , Abelson Robert P. , Salovey Peter
Published: April 2006

Satisfaction with a desired outcome depends both on its position (i.e., the actual value of the outcome) and on its velocity (i.e., the change in the value). In a questionnaire study, we investigated factors that influence the relative weighting of position and velocity in satisfaction and found that the relative weight of velocity loomed larger when the outcome was (a) framed in terms of change (rather than in terms of overall position), (b) related to consummatory (rather than instrumental) behaviors, or (c) internally (rather than externally) controlled. The findings suggest that the relative importance of position and velocity in satisfaction varies, depending on the condition and nature of the outcome.
The Institute of Psychology, USSR: A 20-Year Retrospective
Authors: Solso Robert L.
Published: April 2006

The Institute of Psychology in Moscow became affiliated with the Academy of Sciences (AS USSR) 20 years ago. In this article a brief history of the Academy of Sciences and the Institute of Psychology is presented, along with a critical examination of the Institute's contribution to world psychology. Through an appraisal of laboratories, productivity, and journal articles, it is argued that Soviet psychologists affiliated with the Institute have made a modest impression on world psychology. The reason for the limited contribution is attributed to the lack of support from the Academy, the lack of essential equipment and supplies, the repressive political environment under which scientists have been forced to operate, and ethnocentrism brought about through cultural and physical isolation.
Vagueness, Ambiguity, and the Cost of Mutual Understanding
Authors: Erev Ido , Wallsten Thomas S. , Neal Martha M.
Published: April 2006

We suggest that vague and ambiguous natural language is commonly used to serve the needs of the linguistic community. Specifically, some social dilemmas can he solved by variability in the participants’ behavior, which will occur among self-interested individuals only if they differentially interpret available information. Because imprecise communications are not understood identically by everyone, they benefit society in certain situations by facilitating heterogeneous choices. An experiment demonstrates that the frequency of vague communication increases in a controlled social setting when its use is beneficial for the group.
The Incidental Acquisition of Information from Reading
Authors: West Richard F. , Stanovich Keith E.
Published: April 2006

In a study of ninety college seniors, measures of exposure to print predicted individual differences in vocabulary and cultural literacy after differences in general ability (SAT scores) had been statistically controlled, but did not predict differences in grade point average or knowledge of the field of major (psychology). Measures of exposure to nonprint media (television and films) predicted variance in cultural literacy, but not in vocabulary, after cognitive ability had been controlled. The data challenge the view that knowledge acquisition is determined only by the efficiency of cognitive components that encode and store information. Instead, the results indicate that differences in exposure to information are a significant independent contributor to differences in knowledge across individuals. The investigation further demonstrated the convergent validity of two briefly administered indicators of individual differences in exposure to print.
The Representation of Fictional Information
Authors: Gerrig Richard J. , Prentice Deborah A.
Published: April 2006

Much of the information we encounter every day appears in settings that are clearly marked as fictional (e.g., novels, television, movies). Our studies explore the extent to which information acquired through these fictional worlds is incorporated into real-world knowledge. We used short stories to introduce fictional facts. The first experiment demonstrated that fictional information penetrates into judgments about beliefs, suggesting incorporation. The second experiment demonstrated, nonetheless, that representations of fictional information retain features of compartmentalization. We suggest, accordingly, that readers create hybrid representations of fictional information.
On Similarities between Causal Judgments in Experienced and Described Situations
Authors: Shanks David R.
Published: April 2006

Wasserman (1990a) has reported an experiment that shows that people's attributions of causality in circumstances where they have to make inferences from brief verbal descriptions correspond to the attributions they make in situations where they actually experience causal sequences, and on the basis of that result he has suggested that psychologists should search for general laws of learning that might account for correspondences such as this one. I briefly describe some further similarities that can be obtained between causal judgments in experienced and described situations. However, the suggestion that a common mechanism may be involved in the two cases is questioned. Instead, I suggest that the correspondence is little more than a coincidence: It does not arise from the operation of a common mechanism. Instead, I argue that people, along with other organisms, possess an associative learning mechanism that operates in experienced situations, but we also possess domain-specific causal beliefs and metabeliefs about causation. These latter two types of beliefs play little role in experienced causal situations, but can readily be applied in making causal attributions from descriptions.
Reflections of the Environment in Memory
Authors: Anderson John R. , Schooler Lael J.
Published: April 2006

Availability of human memories for specific items shows reliable relationships to frequency, recency, and pattern of prior exposures to the item. These relationships have defied a systematic theoretical treatment. A number of environmental sources ( New York Times, parental speech, electronic mail) are examined to show that the probability that a memory will be needed also shows reliable relationships to frequency, recency, and pattern of prior exposures. Moreover, the environmental relationships are the same as the memory relationships. It is argued that human memory has the form it does because it is adapted to these environmental relationships. Models for both the environment and human memory are described. Among the memory phenomena addressed are the practice function, the retention function, the effect of spacing of practice, and the relationship between degree of practice and retention.
On the Form of Forgetting
Authors: Wixted John T. , Ebbesen Ebbe B.
Published: April 2006

Almost everyone would agree that the course of forgetting is some curvilinear function of time. The purpose of the research described herein was to identify the nature of that function. Three experiments are reported, two involving human subjects and one involving pigeons. The human experiments investigated this issue using recall of words and recognition of faces, whereas the pigeon experiment employed the standard delayed matching-to-sample task. In all cases, the course of forgetting was best described by a simple power function of time relative to five other reasonable alternatives (linear, exponential, exponential-power, hyperbolic, and logarithmic). Furthermore, a reanalysis of Ebbinghaus's (1885) classic savings function showed that it, too, declines as a power function of time. These findings suggest that the form of forgetting is a relatively robust property of memory performance and that its mathematical description, perhaps only coincidentally, matches that of the psychophysical function.
Making Better use of Scientific Knowledge: Separating Truth from Justice
Authors: Hammond Kenneth R. , Harvey Lewis O. , Hastie Reid
Published: April 2006

One major reason that scientific information is not often effectively applied in the formation of social policy is that available methods for coping with the uncertainty in scientific judgments are overlooked. Application of such methods is as necessary as reducing uncertainty through the acquisition of more knowledge for these methods result in the more effective use of knowledge already at hand. Furthermore, failure to cope with uncertainty through explicit, analytical methods results in failure to separate fact (truth) from value (justice), which in turn results in wasted knowledge and unnecessary dispute. We present four concrete examples of how such circumstances can be avoided.
Representation of Colors in the Blind, Color-Blind, and Normally Sighted
Authors: Shepard Roger N. , Cooper Lynn A.
Published: April 2006

Human adults with normal vision, with three types of color-blindness, or with complete absence of vision since birth rank-ordered the similarities of all pairs of colors corresponding to nine hue names. When presented with the names only, subjects with any color vision produced rankings for which multidimensional scaling yielded Newton's color circle. When subjects were presented with the colors themselves, the recovered color circle remained the same for the normally sighted but collapsed along the red-green dimension for the color-blind. Based on their rankings by color names, the totally blind subjects all fell outside the range of the color-normal subjects but partly overlapped the color-deficient subjects; a rare rod monochromat roughly approximated the color-normal subjects. These results, along with those of Marmor (1978) and Izmailov and Sokolov (this issue), suggest how visual experience, language, and innate structure contribute to the mental representation of colors.
Embracing the Bitter “Truth”: Negative Self-Concepts and Marital Commitment
Authors: Swann William B. , Hixon J. Gregory , De La Ronde Chris
Published: April 2006

We propose that because self-concepts allow people to predict (and thus control) the responses of others, people want to find support for their self-concepts. They accordingly gravitate toward relationship partners who see them as they see themselves. For people with negative self-views, this means embracing relationship partners who derogate them. Our findings confirmed this reasoning. Just as persons with positive self-concepts were more committed to spouses who thought well of them than to spouses who thought poorly of them, persons with negative self-concepts were more committed to spouses who thought poorly of them than to spouses who thought well of them.
What is an “Explanation” of Behavior?
Authors: Simon Herbert A.
Published: April 2006

The cognitive “revolution” in psychology introduced a new concept of explanation and somewhat novel methods of gathering and interpreting evidence. These innovations assume that it is essential to explain complex phenomena at several levels, symbolic as well as physiological; complementary, not competitive. As with the other sciences, such complementarity makes possible a comprehensive and unified experimental psychology. Contemporary cognitive psychology also introduced complementarity of another kind, drawing upon, and drawing together, both the behaviorist and the Gestalt traditions.
On the Framing of Multiple Prospects
Authors: Redelmeier Donald A. , Tversky Amos
Published: April 2006

We investigated decisions involving multiple independent uncertain prospects. At the extremes, a decision maker may either consider each prospect as a separate event (segregation) or evaluate the overall distribution of outcomes (aggregation). Contrary to choice by segregation, people sometimes reject a single gamble but accept a repeated play. On the other hand, people tend to choose by segregation when a particular gamble is singled out from a larger ensemble. Similarly, physicians make different choices when they evaluate problems on a case-by-case basis than when they consider the broader picture. Peoples' tendency to segregate multiple prospects represents a significant violation of the standard theory of rational choice.
On the Role of Symmetry in Visual Search
Authors: Wolfe Jeremy M. , Friedman-Hill Stacia R.
Published: April 2006

It is known that the efficiency of visual search for a target item among distractor items increases when distractors are similar to each other and decreases when target and distractors are similar. Here we show that symmetry relations between targets and distractors can alter search efficiency. When distractors form a background texture symmetrical about a vertical axis, search is easier than when they do not. In contrast, when some distractors are symmetrical with the target, search is more difficult than when they are not. These results suggest (1) that symmetry relations are processed in parallel and can help to distinguish a target from a distracting background and (2) that stimulus similarity can have several components even for a single feature (here, orientation).
The Loss of Positional Certainty in Long-Term Memory
Authors: Nairne James S.
Published: April 2006

Long-term memory for sequential position was examined following retention intervals that ranged from 30 sec to 24 h. The Estes perturbation model (1972) is shown to provide a reasonable qualitative fit of the dynamics of forgetting, even though the model was designed to account for the phenomena of immediate memory. Similarities among the forgetting processes of short-and long-term memory are considered.
Early Androgens Are Related to Childhood Sex-Typed Toy Preferences
Authors: Berenbaum Sheri A. , Hines Melissa
Published: April 2006

Girls with congenital adrenal hyperplasia (CAH) who were exposed to high levels of androgen in the prenatal and early postnatal periods showed increased play with boys” toys and reduced play with girls' toys compared with their unexposed female relatives at ages 3 to 8. Boys with CAH did not differ from their male relatives in play with boys' or girls' toys. These results suggest that early hormone exposure in females has a masculinizing effect on sex-typed toy preferences.
Implicit and Explicit Memory for Verbal Information Presented during Sleep
Authors: Wood James M. , Bootzin Richard R. , Kihlstrom John F. , Schacter Daniel L.
Published: April 2006

This study examined implicit memory for words presented during sleep. Ten experimental subjects were presented with word pairs including a homophone and a close associate (e.g., “tortoise-hare”) and with category-instance pairs (e.g., “bird-cardinal”) during REM or Stage 2 sleep and tested immediately afterward. Twelve control subjects underwent the same procedure while awake. Unlike the controls, subjects in the sleeping condition showed no learning effects on the implicit memory tasks. Recall and recognition were observed in a few cases, but only when presentation was immediately followed by arousal.
Disparate Effects of Repeated Testing: Reconciling Ballard's (1913) and Bartlett's (1932) Results
Authors: Wheeler Mark A. , Roediger Henry L.
Published: April 2006

Bartlett (1932) gave subjects a prose passage and showed how recall dropped when they were tested repeatedly. Ballard (1913), using poetry, and Erdelyi and Becker (1974), using pictures, reported improvements in performance (or hypermnesia) over repeated testing. We investigated two likely factors leading to the discrepant results: the type of material and the interval between tests. The primary cause of the differing outcomes is the interval between tests. In general, when the intervals between successive tests are short improvement occurs between tests. When these intervals are long, forgetting occurs. The type of material used plays little role: Hypermnesia in recall of prose (even “The War of the Ghosts”) occurred with short intervals between tests. We also report a striking confirmation of the power of tests to enhance memory: Repeated tests shortly after study greatly improved recall a week later.
Sex Differences in Jealousy: Evolution, Physiology, and Psychology
Authors: Buss David M. , Larsen Randy J. , Westen Drew , Semmelroth Jennifer
Published: April 2006

In species with internal female fertilization, males risk both lowered paternity probability and investment in rival gametes if their mates have sexual contact with other males. Females of such species do not risk lowered maternity probability through partner infidelity, but they do risk the diversion of their mates' commitment and resources to rival females. Three studies tested the hypothesis that sex differences in jealousy emerged in humans as solutions to the respective adaptive problems faced by each sex. In Study 1, men and women selected which event would upset them more—a partner's sexual infidelity or emotional infidelity. Study 2 recorded physiological responses (heart rate, electrodermal response, corrugator supercilii contraction) while subjects imagined separately the two types of partner infidelity. Study 3 tested the effect of being in a committed sexual relationship on the activation of jealousy. All studies showed large sex differences, confirming hypothesized sex linkages in jealousy activation.
Psychophysical Scaling of Stressful Life Events
Authors: Crandall Christian S.
Published: April 2006

Birnbaum and Sotoodeh ( PS 2(4), 1991, pp. 236–240) used psychophysical techniques to generate severity weightings for the stressful life events from Holmes and Rake's (1967) Social Readjustment Rating Scale. The techniques Birnhaum and Sotoodeh applied are designed to uncover the structure of judgments and decisions, but in the context of predicting physical symptoms, they do not improve on the original weightings published in 1967. Neither the original Holmes and Rahe weights nor Birnbaum and Sotoodeh's weights were significantly better than unit weighting (1 if event occurred, 0 if not) for predicting physical symptoms of 115 college students.
Choice under Conflict: The Dynamics of Deferred Decision
Authors: Tversky Amos , Shafir Eldar
Published: April 2006

Choice often produces conflict. This notion, however, plays no role in classical decision theory, in which each alternative is assigned a value, and the decision maker selects from every choice set the option with the highest value. We contrast this principle of value maximization with the hypothesis that the option to delay choice or seek new alternatives is more likely to be selected when conflict is high than when it is low. This hypothesis is supported by several studies showing that the tendency to defer decision, search for new alternatives, or choose the default option can be increased when the offered set is enlarged or improved, contrary to the principle of value maximization.