Sexual Desire and Depression Following Spinal Cord Injury: Masculine Sexual Prowess as a Moderator

Men’s adherence to masculine norms stressing sexual prowess may contribute to their adjustment to changes in sexual functioning following spinal cord injury. The authors test this hypothesis by examining the moderating role of men’s conformity to gender norms for sexual prowess on the relationship between sexual desire and depression. One hundred and sixteen male citizens of the United States with spinal cord injuries were recruited for participation in the internet-based survey. Results indicated that participants with strong sexual desire evinced higher rates of depression when they conformed to masculine norms emphasizing sexual prowess. Men with little reported sexual desire, by contrast, demonstrated lower rates of depression when they endorsed norms for prowess. Directions for future research and treatment interventions are offered.     

An evolutionary theory of schizophrenia: cortical connectivity, metarepresentation, and the social brain

Schizophrenia is a worldwide, prevalent disorder with a multifactorial but highly genetic aetiology. A constant prevalence rate in the face of reduced fecundity has caused some to argue that an evolutionary advantage exists in unaffected relatives. Here, I critique this adaptationist approach, and review--and find wanting--Crow's "speciation" hypothesis. In keeping with available biological and psychological evidence, I propose an alternative theory of the origins of this disorder. Schizophrenia is a disorder of the social brain, and it exists as a costly trade-off in the evolution of complex social cognition. Paleoanthropological and comparative primate research suggests that hominids evolved complex cortical interconnectivity (in particular, frontotemporal and frontoparietal circuits) to regulate social cognition and the intellectual demands of group living. I suggest that the ontogenetic mechanism underlying this cerebral adaptation was sequential hypermorphosis and that it rendered the hominid brain vulnerable to genetic and environmental insults. I argue that changes in genes regulating the timing of neurodevelopment occurred prior to the migration of Homo sapiens out of Africa 100,000-150,000 years ago, giving rise to the schizotypal spectrum. While some individuals within this spectrum may have exhibited unusual creativity and iconoclasm, this phenotype was not necessarily adaptive in reproductive terms. However, because the disorder shared a common genetic basis with the evolving circuitry of the social brain, it persisted. Thus schizophrenia emerged as a costly trade-off in the evolution of complex social cognition.     

Garner interference is not solely driven by stimulus uncertainty

The speeded classification tasks popularized by Garner (1974), with their accompanying labels of separable and integral dimensions, have become the dominant paradigm for characterizing perceptual interactions between stimulus dimensions. Separable dimensions like color and shape can be selectively attended to at will, but integral dimensions like hue and brightness cannot. When classifying stimuli with respect to a single dimension, integral stimuli lead to faster performance in the baseline block, where only that single dimension varies, than in the filtering block, in which a second dimension is allowed to vary irrelevantly. No such difference is predicted for separable dimensions lead to no difference. The comparison between baseline and filtering confounds a change in the number of stimuli with a change in the number of variant dimensions. A new experimental condition is proposed utilizing three stimulus dimensions to hold the number of stimuli constant while introducing variance along a second irrelevant dimension. Data indicate that interference increases, suggesting that changes in the number of potential stimuli within a block are not necessary for Garner interference, in contrast to the accounts provided by extant quantitative models.     

Learning in a task of complex auditory streaming and identification

Adult humans were studied for improvements in their ability to segregate natural whole speech in background noise, in 6 test sessions spaced with a very wide range of inter-session interval (ISI) ranging from minutes to weeks apart so as to examine the effect of this parameter on initial (early) and late components of perceptual learning. Improvements were found even with spacings of 3 weeks between the punctate task sessions. All subjects showed similar total learning amounts but there were sex- and ISI-dependent differences in learning patterns, which we indexed by dividing the overall exponentially-decreasing learning pattern into an early phase between the first two sessions and a later phase between the second and sixth sessions. Males tested at all ISIs and females tested at short (2, 5 and 15 min) and long (1–21 days) ISIs showed small amounts of early-phase learning and large amounts of late-phase learning. However, females tested at intermediate (30 min and 1 h) ISIs showed only early learning, i.e., faster learning given that the total learning was the same. This sex- and ISI-specific deviant pattern could be changed to the standard pattern by interposing an overnight interruption that included sleep amongst test sessions. Thus, improvement in this complex auditory streaming and identification task can occur even with very brief and widely-spaced exposure, generally through a standard pattern of slower overall learning, but also through a sex- and ISI-specific deviant pattern of very rapid early learning which can be modulated by interposed delay unlike the standard pattern.     

Numerical and sensory categorization of serial information by animals

Rats were trained in a straight runway on a series consisting of 4 elements, each element being defined in terms of the number of .045-gm. Noyes pellets used as reward on 4 runway trials separated by about 20 sec. The series elements were 2, 6, 12, and 0 (2-6-12-0). The animals were trained each day on 3 such series, the series themselves being separated within a day by about 12 min. for 28 days before introducing a new transfer series to assess the relevance of the order of the series elements. In previous experiments with the simpler series, 2-12-0, alterations in order of elements eliminated the animals' tendencies to run much slower to the terminal nonreward element of the series, but transfer was clearly shown here when we shifted from 2-6-12-0 to 6-12-2-0. That is, the animals continued on the transfer test to approach the terminal element slowly, a result which we interpret as supporting the view that the rats either counted the rewarded trials and used that count to predict terminal nonreward, or they behaved on the basis of cues associated with the ordinal position of the trial.     

A Comparison of Two Flashcard Drill Methods Targeting Word Recognition

Traditional drill and practice (TD) and incremental rehearsal (IR) are two flashcard drill instructional methods previously noted to improve word recognition. The current study sought to compare the effectiveness and efficiency of these two methods, as assessed by next day retention assessments, under 2 conditions (i.e., opportunities to respond held constant across methods, length of instructional session held constant across methods) with 4 first-grade students identified by their teachers as struggling readers. Social validity of the two intervention methods also was evaluated. Results suggested important differences in response to instruction across students. Differences in effectiveness between TD and IR were minimal both when holding opportunities to respond and length of instructional session constant across methods. Minimal differences in efficiency were noted between TD and IR when holding instructional time constant across conditions. However, TD was clearly more efficient than IR for all students when holding opportunities to respond constant across conditions. Social validity data indicated that half of the students preferred the TD method and half preferred the IR method. Limitations and implications of the current study for school-based professionals are discussed.     

Adaptive memory: determining the proximate mechanisms responsible for the memorial advantages of survival processing

J. S. Nairne, S. R. Thompson, and J. N. S. Pandeirada (2007) suggested that our memory systems may have evolved to help us remember fitness-relevant information and showed that retention of words rated for their relevance to survival is superior to that of words encoded under other deep processing conditions. The authors present 4 experiments that uncover the proximate mechanisms likely responsible. The authors obtained a recall advantage for survival processing compared with conditions that promoted only item-specific processing or only relational processing. This effect was eliminated when control conditions encouraged both item-specific and relational processing. Data from separate measures of item-specific and relational processing generally were consistent with the view that the memorial advantage for survival processing results from the encoding of both types of processing. Although the present study suggests the proximate mechanisms for the effect, the authors argue that survival processing may be fundamentally different from other memory phenomena for which item-specific and relational processing differences have been implicated. (PsycINFO Database Record (c) 2010 APA, all rights reserved).     

Are Causal Structure and Intervention Judgments Inextricably Linked? A Developmental Study

The application of the formal framework of causal Bayesian Networks to children’s causal learning provides the motivation to examine the link between judgments about the causal structure of a system, and the ability to make inferences about interventions on components of the system. Three experiments examined whether children are able to make correct inferences about interventions on different causal structures. The first two experiments examined whether children’s causal structure and intervention judgments were consistent with one another. In Experiment 1, children aged between 4 and 8 years made causal structure judgments on a three‐component causal system followed by counterfactual intervention judgments. In Experiment 2, children’s causal structure judgments were followed by intervention judgments phrased as future hypotheticals. In Experiment 3, we explicitly told children what the correct causal structure was and asked them to make intervention judgments. The results of the three experiments suggest that the representations that support causal structure judgments do not easily support simple judgments about interventions in children. We discuss our findings in light of strong interventionist claims that the two types of judgments should be closely linked.     

Pointing Disrupts Preschoolers' Ability to Discriminate Between Knowledgeable and Ignorant Informants

By 4 years of age, children have been reinforced repeatedly for searching where they see someone point. In two studies, we asked whether this history of reinforcement could interfere with young children's ability to discriminate between a knowledgeable and an ignorant informant. Children watched as one informant hid a sticker while another turned around, and then both informants indicated where they though the sticker was, either by pointing or by using a less practiced means of reference. Children failed to discriminate between the two informants when they pointed, but they chose the location indicated by the knowledgeable informant when the informants used a cue other than pointing. Pointing can disrupt as basic an understanding as the link between seeing and knowing.