Recovery of single word comprehension: CT-scan correlates

9tory comprehension for single words, as measured by the BDAE Word Discrimination subtest, was studied longitudinally in a group of 37 aphasic patients. The majority of the patients had impaired performance at 1 month postonset, but recovery by Month 6 postonset was quite striking. Damage to Wernicke's area did not preclude recovery of single word comprehension to within the normal range. Only patients with very extensive left hemisphere lesions had incomplete recovery of single word comprehension.     

Developmental differences in memory for temporally neutral and temporally tagged information

Forty children (ages 7 and 11 years) listened to stories and then answered questions about temporally neutral and temporally tagged information appearing in them (e.g., “Linda is smart” vs “Linda ate an apple”). Number of presentations and free recall of the stories were manipulated to study age-related changes in the effects of additional processing on memory for the two kinds of information. Older children exhibited overall better memory, but with additional processing that difference was larger for temporally neutral than for temporally tagged information. The observed interactions among age, additional processing, and kind of information demonstrated the importance of the distinction between temporally neutral and temporally tagged information for developmental studies of memory for prose.     

Keeping track of locations during movement in 8- to 10-month-old infants

Infants of $\text{8}\text{1}\text{2}$ and $\text{9}\text{1}\text{2}$ mo of age were tested for the ability to “keep track,” i.e., to determine the location of an object hidden in one of two covered containers before their left-right positions were reversed. Infants in both age groups for whom the covers were the same color and younger infants for whom the covers were different colors were generally unable to keep track. Only the older infants provided with different colored covers were able to do so. An analysis which separated keeping track from the sensorimotor stage 4 error indicated that (a) there was no contingency between the two and (b) there were developmental differences in the nature of the error.     

Causality assessment in epidemiology

Epidemiology relies upon a broad interpretation of determinism. This paper discusses analogies with the evolution of the concept of cause in physics, and analyzes the classical nine criteria proposed by Sir Austin Bradford Hill for causal assessment. Such criteria fall into the categories of enumerative induction, eliminative induction, deduction and analogy. All of these four categories are necessary for causal assessment and there is no natural hierarchy among them, although a deductive analysis of the study design is preliminary to any assessment.     

EXTENDING THE CONCEPT OF SOCIAL VALIDITY: BEHAVIOR ANALYSIS FOR DISEASE PREVENTION AND HEALTH PROMOTION

A broader definition of social validity is proposed wherein a socially valid behavior-change intervention is directed to a problem of verifiable importance, the intervention is valued and used appropriately by designated target groups, and the intervention as used has sufficient behavioral impact to substantially reduce the probability of the problem's occurrence in target populations. The verifiable importance of a problem is based on epidemiological data, and the value and appropriate use of an intervention are enhanced through the use of conceptual frameworks for social marketing and behavior change and considerable formative and pilot research. Behavioral impact is assessed through efficacy and effectiveness studies. Thus, the social validity of a behavior-change intervention is established through a number of interactive, a priori steps. This approach to defining social validity is related to critical analysis and intervention issues including individual and population perspectives and “top-down” and “bottom-up” approaches to intervention design. This broader definition of social validity is illustrated by a project to reduce the risk of HIV infection among adolescents. Although the various steps involved in creating socially valid interventions can be complicated, time-consuming, and expensive, following all the steps can result in interventions capable of improving a nation's health.     

Developmental differences in frequency judgments of words and pictures

Children in kindergarten, third, and fifth grades were presented a list of either pictures or words (with items presented for varying numbers of times on the study trial). In both picture and word conditions, half of the Ss estimated how many times each item had been presented (absolute judgments) and the other half judged which of two items had occurred more often on the study trial (relative judgments). The primary finding was that while frequency judgment performance improved with age for both pictures and words, there was relatively greater improvement for pictures (i.e., the picture-word difference increased with age). These results lend strong support to the frequency theory of discrimination learning and, in particular, may be useful in accounting for effects associated with age and with age by stimulus mode interactions.     

A developmental study of pronouncing responses in the discrimination learning of words and pictures

Subjects at three age levels were administered picture pair or word pair discrimination lists. They pronounced or pointed as a method of choice, and they pronounced or pointed at the correct item (or remained silent) during rehearsal. The results indicated that with picture pairs, pronunciation facilitated learning as a method of choice and a type of rehearsal in nursery school Ss. For fifth grade and college Ss, there was no significant difference between pronouncing and pointing as a method of choice. However, spoken rehearsal was superior to control performance for fifth grade Ss. College Ss performed equally well in the control and pronouncing conditions, but pointing during rehearsal produced significantly more errors than pronouncing. Word pairs produced no significant pronunciation effects. These results were discussed within an internalization of speech perspective.     

Developmental differences in mental rotation.

A reaction time paradigm was used to investigate developmental differences in ability to rotate and compare imaginal representations. Third grade, fifth grade, and college students (ages 9, 11, and 20 years, respectively) were required to determine whether a letter of the alphabet was presented in its backward or normal position. Letters were presented at 0, 60, 120, 180, 240, or 300° orientations from upright. Subjects were given no advance information about a test letter, or they were given identity and orientation information. In the no information condition, reaction time increased for all age groups as a function of the departure in orientation of the test letter from an upright position. In the advance information condition, reaction time remained uniform across orientation for only the college subjects. The developmental implications of these findings are discussed.     

Formal models of language learning

Research is reviewed that addresses itself to human language learning by developing precise, mechanistic models that are capable in principle of acquiring languages on the basis of exposure to linguistic data. Such research includes theorems on language learnability from mathematical linguistics, computer models of language acquisition from cognitive simulation and artificial intelligence, and models of transformational grammar acquisition from theoretical linguistics. It is argued that such research bears strongly on major issues in developmental psycholinguistics, in particular, nativism and empiricism, the role of semantics and pragmatics in language learning, cognitive development, and the importance of the simplified speech addressed to children.