The visual cliff: cardiac and behavioral responses on the deep and shallow sides at five and nine months of age

Cardiac and behavioral reactions of 5- and 9-month-old infants placed directly atop the two sides of the visual cliff were studied. Evidence of a developmental shift in infant responses on the deep side of the cliff was obtained in heart rate, which shifted from the deceleration previously obtained with younger subjects, to the acceleration obtained with the 9-month-olds of the present study. Behaviorally, visual attention on the two sides was similar at 5 months, but differed at 9 months, being significantly greater on the deep side. Limb movement showed less of an increase on the deep side than on the shallow at both ages tested. Negative vocalization and positive vocalization recordings failed to show any significant effects. The cardiac data are interpreted as indicating a possible shift from attentiveness to fearfulness on the deep side with age.     

Components of verbal learning in children: Analysis by selective reminding

Free recall verbal learning by 5- and 8-year-old children was analyzed by selectively reminding them only of items not recalled on the preceding trial (instead of continuing to present the entire list before each recall trial) to show learning by retrieval from long-term storage without presentation. Concurrent analysis of long-term storage, consistent and random retrieval from long-term storage, and recall from short-term storage indicates that, while 5-year-olds showed slower acquisition than 8-year-olds, lower recall by 5-year-olds also was due to less effective retrieval from longterm storage. Repeated retrieval, without any further presentation after an item has been recalled just once, indicates that lower recall by 9-year-old children than by adults also reflects retrieval difficulty, since these children showed storage and retention of almost as many items as adults by eventual spontaneous retrieval without further presentation.     

Resistance to yielding and the expectation of cooperative future interaction in negotiation

The expectation of cooperative future interaction (ECFI) encouraged especially high joint benefit (the total of the two bargainers' individual outcomes) when resistance to yielding was high, but especially low joint benefit when resistance to yielding was low. Process data suggest that this finding can be explained as follows: When resistance to yielding is high, ECFI encourages problem solving and reduced contentious behavior; when resistance to yielding is low, ECFI encourages a collapse of aspirations. The results support Filley's (1975) dualconcern model and cast doubt on Deutsch's (1973) blanket assertion that a cooperative process leads to constructive conflict resolution.     

The effects of word class on children's reading and spelling

Children's oral language functioning has been shown to be affected by word class (i.e., content vs. noncontent words). The present study reveals comparable effects on children's written language performance. In spelling and reading, third and fifth graders show faster and more accurate responses to nouns and verbs than to noncontent words of matched length and frequency. Further, when the children's performance is examined in relation to level of reading skill, it is found that the less-skilled readers exhibit a greater content/noncontent differential than do the more skilled readers. The results are discussed with reference to differential access for the two word classes and its implication for both oral and written language functioning.     

Encoding variability and organization in free recall

Measures of category clustering and subjective organization are well-established predictors of performance in free recall tasks. The present studies demonstrate that a measure of encoding variability affords equally powerful and independent prediction of free recall performance. They also illustrate an interaction between encoding processes and organizational activity. In Experiments 1 and 2, the independent contributions of organization and encoding variability are demonstrated in categorizable and uncategorizable lists and in subjects whose recall is expected to increase (adults) or decrease (children) as a function of more varied encodings across trials. In Experiment 3, a category labeling procedure is used to demonstrate that the negative relationship between encoding variability and recall can be reversed by inducing adult-like organizational activity in children.     

From response-set to prediction hypotheses: Rule acquisition among preschoolers and second graders

It was proposed that prediction hypotheses do not emerge full blown in the repertoire of the young child. Instead, the component units out of which predictions are consolidated (win-stay, lose-shift) are acquired independently and at different rates. The young child's behavior is at first dominated by response sets in which the win and lose components involve the same action (win-stay, lose-stay or win-shift, lose-shift). The components of response sets must be separated and coordinated with task-relevant information before appropriate components are consolidated to yield prediction hypotheses. A combination of learning-set and blank-trial procedures was used to evaluate this conception with preschoolers (mean CA = 4:1) and second graders (mean CA = 7:6). Results revealed that children of both age levels exhibited response patterns that corresponded to hypotheses in most of their probes (.89 to. 98). The striking finding was the relative weakness of win-stay on object cues at the outset of acquisition, particularly among the younger children. In contrast. lose-shift object was strong from the outset among children of both age levels. Once the two components (win-stay object, lose-shift object) were consolidated, the resulting scheme was durable, in that transfer to more complex problems was nearly perfect. Children who did not achieve criterion (in 70 problems) failed because they exhibited mostly position hypotheses and/or because the strength of win-stay object remained weak throughout all sessions.     

The development of procedural knowledge: An alternative explanation for chronometric trends of mental arithmetic

In a review of the Chronometrie literature, M. H. Ashcraft (Developmental Review, 1982, 2, 213–236) concluded that the development of number fact efficiency is due to a shift from relying on procedural knowledge such as counting to relying on declarative knowledge (a stored network of facts). This model assumes that all procedural processes are slow or remain slow, which is probably not the case. An alternative account posits that the key change in number fact efficiency involves a shift from slow counting procedures to principled procedural knowledge. As rules, heuristics, and principles become more familiar and interconnected, their use, for example, in producing the number facts becomes more automatic. The use of such procedural knowledge would be cognitively more economical than storing individual facts in long-term memory. Finally, existing Chronometric data can readily be interpreted in terms of this alternative model.