Reasoning from inconsistency to consistency

This article presents a theory of how individuals reason from inconsistency to consistency. The theory is based on 3 main principles. First, individuals try to construct a single mental model of a possibility that satisfies a current set of propositions, and if the task is impossible, they infer that the set is inconsistent. Second, when an inconsistency arises from an incontrovertible fact, they retract any singularly dubious proposition or any proposition that is inconsistent with the fact; otherwise, they retract whichever proposition mismatches the fact. A mismatch can arise from a proposition that has only mental models that conflict with the fact or fail to represent it. Third, individuals use their causal knowledge-in the form of models of possibilities-to create explanations of what led to the inconsistency. A computer program implements the theory, and experimental results support each of its principles.     

Quality of life assessment in Turkish patients with schizophrenia and their relatives

Quality of life of first-degree relatives living in the same household with patients having schizophrenia has not been sufficiently explored. 30 patients with schizophrenia (16 women, 14 men), diagnosed using DSM-IV criteria, 31 of their relatives (15 women, 16 men), and 34 control subjects (21 women, 13 men) were included in the study. The mean age of the patients, their relatives, and the control subects were 39.8 +/- 10.9, 58.1 +/- 12.5 and 37.3 +/- 17.0, respectively. The World Health Oranization Quality of Life-Brief Form was administered to all subjects. Quality of life was worse for the patient group than for their relatives and control subjects, but relatives of the patients and control subjects were not significantly different on Quality of life. Quality of life was negatively correlated with the severity of psychopathology and extrapyramidal side effects induced by antipsychotic drugs in the patients.     

Holography does not account for goodness: a critique of van der Helm and Leeuwenberg (1996)

P. A. van der Helm and E. L. J. Leeuwenberg (1996) outlined a holographic account of figural goodness of a perceptual stimulus. The theory is mathematically precise and can be applied to a broad spectrum of empirical data. The authors argue, however, that the account is inadequate on both theoretical and empirical grounds. The theoretical difficulties concern the internal consistency of the account and its reliance on unspecified auxiliary assumptions. The account also makes counterintuitive empirical predictions, which do not fit past data or the results of a series of new experimental studies.     

The Relative Influence of Client Characteristics on the Process and Outcomes of Premarital Counseling: A Survey of Providers

To explore the influence of client characteristics in premarital counseling, a five factor model is presented that includes the social context, family-of-origin influences, individual characteristics, couple interactional processes, and motivation for attending premarital counseling. The findings demonstrate that providers believe that many client characteristics influence the degree to which couples benefit from premarital counseling. Providers rated the influence of the client characteristic factors in the following order (from most to least influential): couple interactional processes, family-of-origin influences, individual characteristics, motivation for premarital counseling, and the social context. Recommendations for future theory development, practice, and research are discussed.The findings presented in this article were part of the authors doctoral dissertation at the University of Florida.     

Bimanual coordination dynamics in poststroke hemiparetics

Poststroke hemiparetic individuals (n = 9) and a control group (n = 9) completed a frequency-scaled circle-drawing task in unimanual and bimanual conditions. Measures of intralimb spatial and temporal task accuracy and interlimb coordination parameters were analyzed. Significant reductions in task performance were seen in both limbs of the patients and controls with the introduction of bimanual movement. Spatial performance parameters suggested that the 2 groups focused on different hands during bimanual conditions. In the controls, interlimb coordination variables indicated predictable hand dominance effects, whereas in the patient group, dominance was influenced by the side of impairment and prior handedness of the individual. Therefore, in this particular bimanual task, performance improvements in the hemiplegic side could not be elicited. Intrinsic coupling asymmetries between the hands can be altered by unilateral motor deficits.     

Prepared movements are elicited early by startle

A startle stimulus has been shown to elicit a ballistic response in a reaction time (RT) task at very short latencies without involvement of the cerebral cortex (J. Valls-Sole, J. C. Rothwell, F. Gooulard, G. Cossu, & E. Munoz, 1999). The present authors examined the nature of the startle response. A simple RT task was used in which 8 participants performed arm extension movements to 3 target distances (20 degrees, 40 degrees, and 60 degrees ) in a blocked design. An unpredictable startling acoustic stimulus (124 dB) replaced the imperative stimulus in certain trials. The authors verified the presence of a startle response independent from the prepared response by observing electromyographic (EMG) activity in sternocleidomastoid and orbicularis oculi muscles. Findings indicated that when the participant was startled, the intended voluntary response was produced at significantly shorter response latencies. Furthermore, the kinematic variables of the observed response during startle trials for all 3 target distances were mostly unchanged. The EMG characteristics of the responses were not modified, indicating that the response produced was indeed the prepared and intended response.     

Effect of upcoming reward type when rats press a lever for ethanol

Rats' operant responding for sucrose rewards in the 1st half of a session can vary directly with the conditions of reward in the 2nd half. The authors investigated whether that induction effect represented an animal model of emotive states. Rats pressed a lever for either ethanol or sucrose rewards in the 1st half of a 40-min session. The reward in the 2nd half of the session was, across conditions, 1% sucrose, a food pellet, or the same reinforcer delivered in the 1st half. When subjects responded for sucrose, upcoming reward type had little influence on responding in the 1st half of the session. However, when subjects responded for ethanol, upcoming 1% sucrose and food-pellet reinforcement both produced increases in responding. The results suggest that the procedure produced different emotive states, but further work is needed to support such a model. The results also have potential applied implications.     

Young children's sensitivity to probabilistic phonotactics in the developing lexicon

A series of three experiments examined children's sensitivity to probabilistic phonotactic structure as reflected in the relative frequencies with which speech sounds occur and co-occur in American English. Children, ages 212 and 312 years, participated in a nonword repetition task that examined their sensitivity to the frequency of individual phonetic segments and to the frequency of combinations of segments. After partialling out ease of articulation and lexical variables, both groups of children repeated higher phonotactic frequency nonwords more accurately than they did low phonotactic frequency nonwords, suggesting sensitivity to phoneme frequency. In addition, sensitivity to individual phonetic segments increased with age. Finally, older children, but not younger children, were sensitive to the frequency of larger (diphone) units. These results suggest not only that young children are sensitive to fine-grained acoustic-phonetic information in the developing lexicon but also that sensitivity to all aspects of the sound structure increases over development. Implications for the acoustic nature of both developing and mature lexical representations are discussed.     

What makes an insight problem? The roles of heuristics, goal conception, and solution recoding in knowledge-lean problems

Four experiments investigated transformation problems with insight characteristics. In Experiment 1, performance on a version of the 6-coin problem that had a concrete and visualizable solution followed a hill-climbing heuristic. Experiment 2 demonstrated that the difficulty of a version of the problem that potentially required insight for solution stems from the same hill-climbing heuristic, which creates an implicit conceptual block. Experiment 3 confirmed that the difficulty of the potential insight solution is conceptual, not procedural. Experiment 4 demonstrated the same principles of move selection on the 6-coin problem and the 10-coin (triangle) problem. It is argued that hill-climbing heuristics provide a common framework for understanding transformation and insight problem solving. Postsolution receding may account for part of the phenomenology of insight.     

Distant melodies: statistical learning of nonadjacent dependencies in tone sequences

Human listeners can keep track of statistical regularities among temporally adjacent elements in both speech and musical streams. However, for speech streams, when statistical regularities occur among nonadjacent elements, only certain types of patterns are acquired. Here, using musical tone sequences, the authors investigate nonadjacent learning. When the elements were all similar in pitch range and timbre, learners acquired moderate regularities among adjacent tones but did not acquire highly consistent regularities among nonadjacent tones. However, when elements differed in pitch range or timbre, learners acquired statistical regularities among the similar, but temporally nonadjacent, elements. Finally, with a moderate grouping cue, both adjacent and nonadjacent statistics were learned, indicating that statistical learning is governed not only by temporal adjacency but also by Gestalt principles of similarity.