A developmental study of learning disabilities and memory

Seven-, ten-, and thirteen-year-old learning-disabled (LD) and non-learning-disabled (NORM) children were presented specially structured lists of 38 words each and tested for free recall. Each list contained only four semantically related words. Two of the four related words were presented contiguously (serial positions 9 and 10) and the other two words were spaced (serial positions 20 and 30). All children recalled disproportionately more adjacent words (item 9 or 10) than any other words. Spaced words (items 20 and 30) were less likely to be recalled by the younger children than by the older children and by the LDs than by the NORMS. These findings provided support for the distinction between automatic and purposive semantic processing. NORMs' recall was governed by purposive semantic processing to a greater extent than was LDs' recall. However, no group or age differences were observed in automatic semantic processing.     

Why versus how often: Causal reasoning and the incidence of judgmental bias

When faced with the task of making a prediction or estimating a likelihood, it is argued that people often reason about the presence or absence and relative strength of possible causal mechanisms for the production of relevant outcomes. In so doing people rely on “causal cues” or properties of an inferential problem which indicate the nature of the particular causal processes which give rise to specific outcomes. It is hypothesized that causal cues, precisely because they focus attention and thought on specific causal mechanisms, can obscure the relevance of mathematical laws of probability and lead to statistically biased judgment. Two experiments were conducted. Their results support the hypothesis, showing that the incidence of the conjunction fallacy and the base rate fallacy depend on task-specific cues for causal reasoning.     

Children's numerical skill and judgments of confidence in estimation

This study investigated how children's fluent use of a basic numerical skill is related to their perceptions of confidence on a task of quantitative estimation. One hundred four 10th graders (age 15.7 years) were categorized according to level of numerical fluency as assessed by timed tasks of counting in various nonunity increments. They then made estimates of large numbers of dots and rated how confident they were on each trial. The estimation task varied according to two within-subject factors of task difficulty. It was found that counting skill was related not only to accuracy in estimating, but also to the appropriateness of the children's confidence in their responses. Skillful children made judgments that corresponded with actual task difficulty. A derived calibration score corroborated ANOVA findings of the interaction of skill level and task difficulty on confidence ratings. It also revealed that while girls were less confident than boys, they were actually more realistic in their judgments. Findings are discussed in terms of (a) the effect of stimulus knowledge on awareness of task difficulty and (b) sex differences in achievement-related expectancies.     

Spontaneous translation and language mixing in a polyglot aphasic

The literature on language mixing in polyglot aphasics is reviewed and a case report of a patient with spontaneous translation is presented. A microgenetic model of language processing provides an interpretive framework for language mixing and spontaneous translation as symptoms of polyglot aphasia. It is suggested that language mixing reflects a deficit at the linguistic level while spontaneous translation reflects a deficit at the prelinguistic level of language processing. A hypothesis about the organization of multiple languages in a single speaker is proposed.     

Psychological studies of children who have cancer

Increasingly, more optimistic prognoses for children who have cancer have led investigators to study the adjustment reactions of children who survive this traumatic experience. There is considerable evidence that the experience of having cancer, receiving prolonged and often painful treatment, and the uncertain condition of cancer survivorship have profound emotional effects on children. The characteristic features of the psychological impact of cancer are the experience of continuing uncertainty in a life-threatening crisis and the resultant search for meaning. Studies are beginning to find that even very young children actively struggle to organize and make sence of this experience.     

The structure of coordination in first language acquisition of Mandarin Chinese: evidence for a universal

This study exemplifies a type of cross-linguistic research which is based on the theory that certain parameters of natural language variation are central to the human competence for language. Sensitivity to these parameters allows the child to develop various specific language structures which follow from setting the parameters. Results of this study provide evidence that children are universally sensitive to one such parameter, namely, Principal Branching Direction.Data are based on results of a standardized elicited imitation test of 68 Chinese children in Taiwan between 2;0 and 4;5 with mean age of 3;3. The test is on a set of coordinate sentences. The results show that children acquiring Mandarin Chinese (a left-branching language) systematically prefer VO sentences with a backward reduction pattern ([V + V]O) over those with a forward reduction pattern (V[O + O]).Children's responses to SV coordinate sentences differ systematically from their VO responses. They very frequently reduce redundant subjects in a forward direction (in SV sentences) and do not prefer backward reduction ([S + S])V) over forward reduction (S[V + V]) in these SV sentences.This paper suggests an explanation of this apparent paradox in terms of an interaction in early language acquisition between children's sensitivity to a predominant Chinese topic-comment structure (in SV) and their sensitivity to the abstract, specifically grammatical concept of “Principal Branching Direction”.     

The ambiguity of recognition memory tests of schema theories

The majority of theories about the effects of schemata (or generic knowledge structures) on information processing share two fundamental assumptions. It is assumed, first, that schema-based inferences about unobserved features of an event are generated, and, second, that such inferences are stored in long-term memory and thereby confused with traces of observed features of that event. To test these assumptions, researchers rely heavily on recognition memory measures of hit and false alarm rates. In the present paper, it is observed that schema theoretic interpretations of recognition memory measures are inconsistent with an interpretation jointly derived from the theory of signal detection and Mandler's (1980, Psychological Review, 87, 252–271) subjective familiarity theory of recognition memory; from the latter's perspective, recognition memory measures are considerably more ambiguous than schema researchers realize and do not necessarily support the typical schema theoretic interpretations. Data from four experiments are analyzed from the perspective of the theory of signal detection/ subjective familiarity model and demonstrate the ambiguity of recognition memory measures for testing hypotheses about the function and consequences of schemata for information processing.     

Selective looking: Attending to visually specified events

Subjects looked at two optically superimposed video sccreens, on which two different kinds of things were happening. In the principal condition, they were required to follow the action in one episode (by pressing keys when significant events occurred) and ignore the other. They could do this without difficulty, although both were present in the same fully overlapped visual field. Odd events in the unattended episode were rarely noticed. It was very difficult to monitor both episodes at once. Performance was no better when the two episodes were presented to different eyes (dichoptic condition) than when both were given binocularly. It is argued that selective attention does not involve special mechanisms to reject unwanted information, but is a direct consequence of skilled perceiving.     

Stimulus intrusion on fixed-interval responding in the rat: The effects of electric shock intensity,temporal location,and response contingency

After a scalloped lever-press response pattern had developed under a fixed-interval food reinforcement schedule, a 15-sec electric shock was intruded for different groups of rats in the first, second, third, or fourth quarter of each inter-reinforcement interval. Shock intensity was systematically increased for individual rats over 70 sessions, from 0.05 to 1.6 mA. Additional between-groups comparisons involved response-dependent versus clock-dependent fixed-interval schedules, and response-dependent versus response-independent electric shock intrusion. Response rates within each fixed interval prior to, during, and following electric shock intrusion showed regular and reproducible increases and decreases under systematic application of the experimental variables. These results provide further evidence that the functions of a stimulus are determined in part by the parameters of intensity, response contingency, and temporal location with respect to reinforcement.