Acoustical determinants of the “neurotic pattern” in rats

The Psychological Record - The experiments reported in the present paper show that the peculiar behavior called the “neurotic pattern” by Maier is dependent upon the intensity and the...     

Structural packaging in the input to language learning: Contributions of prosodic and morphological marking of phrases to the acquisition of language

The linguistic input to language learning is usually thought to consist of simple strings of words. We argue that input must also include information about how words group into syntactic phrases. Natural languages regularly incorporate correlated cues to phrase structure, such as prosody, function words, and concord morphology. The claim that such cues are necessary for successful acquisition of syntax was tested in a series of miniature language learning experiments with adult subjects. In each experiment, when input included some cue marking the phrase structure of sentences, subjects were entirely successful in learning syntax; in contrast, when input lacked such a cue (but was otherwise identical), subjects failed to learn significant portions of syntax. Cues to phrase structure appear to facilitate learning by indicating to the learner those domains within which distributional analyses may be most efficiently pursued, thereby reducing the amount and complexity of required input data. More complex target systems place greater premiums on efficient analysis; hence, such cues may be even more crucial for acquisition of natural language syntax. We suggest that the finding that phrase structure cues are a necessary aspect of language input reflects the limited capacities of human language learners; languages may incorporate structural cues in part to circumvent such limitations and ensure successful acquisition.     

Obese, older adults with knee osteoarthritis: weight loss, exercise, and quality of life.

This study examined the effects of dietary weight loss and exercise on the health-related quality of life (HRQL) of overweight and obese, older adults with knee osteoarthritis. A total of 316 older men and women with documented evidence of knee osteoarthritis were randomly assigned to 1 of 4 18-month interventions: dietary weight loss, exercise, dietary weight loss and exercise, or healthy lifestyle control. Measures included the SF-36 Health Survey and satisfaction with body function and appearance. Results revealed that the combined diet and exercise intervention had the most consistent, positive effect on HRQL compared with the control group; however, findings were restricted to measures of physical health or psychological outcomes that are related to the physical self.     

Methodological issues in the assessment of sustained performance

In both military and industrial work settings, it has become desirable, and in many instances necessary, to require sustained performance beyond the apparently optimal 8-h workday. Research in this area may be viewed historically as having been focused in three major areas: (1) determining appropriate methodologies for measuring sustained performance, (2) investigating factors that influence sustained performance, and (3) searching for ways to enhance performance during sustained operations. On the basis of discussions held in Toronto in August 1984, observations are drawn and recommendations are made concerning the directions and content of future research.     

Pathways from Birth Weight to ADHD Symptoms through Fluid Reasoning in Youth with or without Intellectual Disability

Although individual differences in fluid reasoning reliably mediate predictions of attention-deficit/hyperactivity disorder (ADHD) symptoms from birth weight in youth with typical cognitive development (TD), it is unknown if this indirect effect operates similarly in the development of ADHD symptoms secondary to intellectual disability (ID). Thus, we evaluated mediation by fluid reasoning in a longitudinal sample of 163 youth (45% female) with (n = 52) or without (n = 111) ID who were followed prospectively from age 5 to age 13. At age 9, youth completed the Arithmetic subtest of the Wechsler Intelligence Scale for Children, a measure of fluid reasoning. At ages 9 and 13, mothers and teachers separately rated youth ADHD symptoms and mothers completed a diagnostic interview. Mediation was tested via path analysis with bootstrapped confidence intervals, and moderated mediation estimated whether indirect effects differed between ID and TD youth or based on youth IQ. Controlling for demographic factors and age 9 ADHD symptoms, age 9 Arithmetic mediated birth weight and multi-method/informant age 13 ADHD symptoms, such that birth weight positively predicted Arithmetic, which negatively predicted ADHD symptoms. Neither ID status nor IQ moderated the observed indirect effect through Arithmetic, suggesting that it was similar for ID and TD youth as well as across the range of youth IQs. These findings support previous evidence that fluid reasoning, as measured by Arithmetic, may causally mediate birth weight and ADHD symptoms, and suggest that this pathway operates similarly with respect to the development of ADHD symptoms in youth with ID.