Homelessness in the United States. An ecological perspective.

This article presents an ecological perspective on homelessness that emphasizes the context in which homeless people live and the complex interactions between personal, social, economic, and service system resources that affect their well-being. The ecological perspective encourages researchers and program developers to assess the problems of homelessness at multiple levels of analysis, to view homelessness as a result of contextual factors that interact with individual and family vulnerabilities, and to assess carefully the social contexts in which researchers and program developers operate. Four ecological principles are described as a heuristic for research, intervention, and policy development. The implications of an ecological perspective for psychologists who wish to get involved in dealing with homelessness are discussed.     

Statistical computations over a speech stream in a rodent

Statistical learning is one of the key mechanisms available to human infants and adults when they face the problems of segmenting a speech stream (Saffran, Aslin, & Newport, 1996) and extracting long-distance regularities (G6mez, 2002; Pe?a, Bonatti, Nespor, & Mehler, 2002). In the present study, we explore statistical learning abilities in rats in the context of speech segmentation experiments. In a series of five experiments, we address whether rats can compute the necessary statistics to be able to segment synthesized speech streams and detect regularities associated with grammatical structures. Our results demonstrate that rats can segment the streams using the frequency of co-occurrence (not transitional probabilities, as human infants do) among items, showing that some basic statistical learning mechanism generalizes over nonprimate species. Nevertheless, rats did not differentiate among test items when the stream was organized over more complex regularities that involved nonadjacent elements and abstract grammar-like rules.     

Body mass index in female Spanish Olympic athletes

The purpose of this study was to examine the Body Mass Index of 180 female Spanish Olympic athletes (M age = 27.1 yr., SD = 5.9 yr.) who participate in presentation sports and nonpresentation sports, in comparison with 114 female nonathletes (M age = 20.7, SD = 1.5 yr.). Presentation sports athletes have a profile similar to that of a university student but by age with a lower Body Mass Index. In particular, rhythmic gymnasts have a lower weight and Body Mass Index than other athletes and nonathletes.     

Effects of backward speech and speaker variability in language discrimination by rats

Human infants use prosodic cues present in speech to extract language regularities, and it has been suggested that this capacity is anchored in more general mechanisms that are shared across mammals. This study explores the extent to which rats can generalize prosodic cues that have been extracted from a training corpus to new sentences and how this discrimination process is affected by the normalization of the sentences when multiple speakers are introduced. Conditions 1 and 2 show rats' abilities to use prosodic cues present in speech, allowing them to discriminate between sentences not previously heard. But this discrimination is not possible when sentences are played backward. Conditions 3 and 4 show that language discrimination by rats is also taxed by the process of speaker normalization. These findings have remarkable parallels with data from human adults, human newborns, and cotton-top tamarins. Implications for speech perception by humans are discussed.     

A new model of sportive cooperation and its evaluation by means a questionnaire

We present in this paper the sportive cooperation as a theoretical framework for the teams' dynamics, and as an alternative to others theories, specially the sportive cohesion. This theory has a double basis: 1) The rational and utilitarist decision taking upon the personal cooperation or not, with the team's goal, based on the internal teammates interaction, and the environmental stimuli; and 2) A personal, and more stable, disposition to cooperate, despite the possibility of obtain any counterparts for this behavior. From this framework, we have build--in a three phase process--a questionnaire addressed to evaluate the sportive cooperation. The final version--composed of 15 items with standard psychometric propierties--shows two kinds of factors. First, we have two dispositional, traitlike, factors: The Conditional cooperation, and the Unconditional cooperation. Second, we have three situational factors: the Cooperation with the Coach, with the teammates, and the Cooperation outside the game and the training. Lastly, we discuss the maining of this theory respect to the sportive team's dynamics, and its relevance for the applied psychology, both for the evaluation and the interventions on the teams.     

Homelessness in the United States: Assessing Changes in Prevalence and Public Opinion, 1993–2001

A national survey was administered in 1993-1994 (N = 360) and repeated in 2001 (N = 435) to assess the prevalence of homelessness as well as attitudes, opinions and knowledge regarding homelessness. No significant changes in prevalence were found, despite a strong US economy during most of the 7-8 year period. Respondents in 2001 had less stereotyped views of homeless people and were more supportive of services, but came to see homelessness as a less serious problem that was less often due to economic factors. This "mixed" set of findings may reflect both beliefs on the benefits of a good economy and an increased awareness of the complexity of homelessness. Across the surveys, younger, female, liberal, and less wealthy respondents demonstrated more sympathetic attitudes towards homeless people.     

Clock drawing performance and brain morphology in mild cognitive impairment and Alzheimer's disease

The Clock Drawing Test (CDT) is a widely used instrument in the neuropsychological assessment of Alzheimer's disease (AD). As CDT performance necessitates several cognitive functions (e.g., visuospatial and constructional abilities, executive functioning), an interaction of multiple brain regions is likely. Fifty-one subjects with mild cognitive impairment, 23 with AD and 15 healthy controls underwent high-resolution magnetic resonance imaging. Optimized voxel-based morphometry (VBM) was performed to investigate the putative association between CDT performance and gray matter (GM) density throughout the entire brain. In the first step of analysis (p<.001, uncorrected), VBM revealed a reduced GM density in numerous cortical (temporal lobe, frontal lobe, parietal lobe, cerebellum) and subcortical (thalamus, basal ganglia) brain regions to be associated with poorer CDT performance. When corrected for multiple comparisons (p<.01), the associations remained significant predominantly in the left temporal and--less pronounced--the right temporal lobe. VBM demonstrated CDT performance to depend on the integrity of widely distributed cortical and subcortical areas in both brain hemispheres with accentuation in the left-sided temporal lobe region.     

Evaluating professionally operated and self-help programs for the seriously mentally ill

Reviewed a study by Bond et al. (1990) that evaluates assertive community treatment (ACT), an intensive community-based program for the seriously mentally ill. Such programs have been developed at a rapid pace in recent years but lack extensive research support. This randomized study supports the effectiveness of ACT and is a significant contribution to the mixed findings from the existing literature. However, its methodological flaws include (a) differential dropout from the ACT and comparison groups, (b) a relatively short follow-up period (12 months), and (c) limitations of the ACT intervention which prevents rehospitalization but lacks impact in other domains (e.g., social relationships, housing stability, employment). Self-help programs, poorly represented by the comparison group in this research, may offer the sorts of societal niches required by the mentally ill. Further research, giving such programs a "fair shake" against professionally controlled programs, is sorely needed.     

Do humans and nonhuman animals share the grouping principles of the iambic–trochaic law?

The iambic–trochaic law describes humans’ tendency to form trochaic groups over sequences varying in pitch or intensity (i.e., the loudest or highest sounds mark group beginnings), and iambic groups over sequences varying in duration (i.e., the longest sounds mark group endings). The extent to which these perceptual biases are shared by humans and nonhuman animals is yet unclear. In Experiment 1, we trained rats to discriminate pitch-alternating sequences of tones from sequences randomly varying in pitch. In Experiment 2, rats were trained to discriminate duration-alternating sequences of tones from sequences randomly varying in duration. We found that nonhuman animals group sequences based on pitch variations as trochees, but they do not group sequences varying in duration as iambs. Importantly, humans grouped the same stimuli following the principles of the iambic–trochaic law (Exp. 3). These results suggest the early emergence of the trochaic rhythmic grouping bias based on pitch, possibly relying on perceptual abilities shared by humans and other mammals, whereas the iambic rhythmic grouping bias based on duration might depend on language experience.     

The role of perceptual salience during the segmentation of connected speech

Statistical learning allows listeners to track transitional probabilities among syllable sequences and use these probabilities for subsequent speech segmentation. Recent studies have shown that other sources of information, such as rhythmic cues, can modulate the dependencies extracted via statistical computation. In this study, we explored how syllables made salient by a pitch rise affect the segmentation of trisyllabic words from an artificial speech stream by native speakers of three different languages (Spanish, English, and French). Results showed that, whereas performance of French participants did not significantly vary across stress positions (likely due to language-specific rhythmic characteristics), the segmentation performance of Spanish and English listeners was unaltered when syllables in word-initial and word-final positions were salient, but it dropped to chance level when salience was on the medial syllable. We argue that pitch rise in word-medial syllables draws attentional resources away from word boundaries, thus decreasing segmentation effectiveness.