Posthypnotic amnesia for recently learned material: Interactions with “episodic” and “semantic” memory

In two experiments, posthypnotic amnesia was suggested for a word list memorized during hypnosis. After an initial test of amnesia the subjects gave word associations (Experiment 1) or category instances (Experiment 2) to stimuli intended to elicit the critical (word list) items covered by the amnesia. The extent of initial amnesia observed was strongly associated with measured hypnotic susceptibility. Even among the most hypnotizable subjects, however, the dense amnesia did not prevent the critical items from being elicited by the semantic memory tasks, nor did it modulate the priming which these associations received by virtue of the prior learning experience. Moreover, production of the critical items did not, in general, remind the amnesic subjects of those items which they had previously learned, but could not now remember. Full memory was restored after the amnesia suggestion was canceled by a prearranged cue. Posthypnotic amnesia appears to represent a temporary dissociation of episodic features from memory traces, so that the subject has difficulty in reconstructing the context in which the target events occurred.     

Children's knowledge of the separation of variables concept

Children 8, 10, and 13 years of age were either given prior experience constructing seriations or matrices with two-dimensional stimuli, or no prior experience. Knowledge of the separation of variables concept was then assessed by examining children's use of controlled tests of a problem variable's effect (probe questions), and recognition of the inadequacy of confounded variable tests (negative counter-suggestion questions). Although many children either passed both questions or failed both questions, a significant number of children correctly used controlled variable tests, and yet failed to recognize the inadequacy of a confounded test. These results suggest that although a preliminary form of the separation of variables concept is characterized by use of controlled variable tests, subsequent refinement of the concept includes recognition of the inadequacy of confounded tests. Relative to seriation, prior experience constructing matrices facilitated recognition of a confounded test's inadequacy. Constructing matrices may have focused attention on the simultaneous variation of problem elements on multiple dimensions and thus facilitated recognition of the necessary role of both variation of stimuli on test dimensions and equality of stimuli on nontest dimensions, e.g., a controlled test.     

Quantifiers and question answering in young children

Two hypotheses were tested about how young children answer questions with the quantifiers all and some: (a) that children use syntactic cues in determining which noun phrase is quantified, and (b) that children evaluate a some-statement as part of evaluating an all-statement. To test these hypotheses, the same group of 60 4- to 7-year-olds were asked four contrasting types of quantitative questions. The results indicated that children can use syntactic cues under some presentation conditions. However, there was no evidence for an asymmetry between the all-and some-questions. A model of how young children might answer quantitative questions was then considered.     

A new measure for determining children's subjective organization of speech

A new technique for determining children's subjective organization of speech is described. The technique consists of teaching a child a sentence and then repeatedly (1) reading the sentence up to a selected point, (2) sounding a tone, and (3) having the child supply the next word. The time from the tone to the onset of the child's voice is the dependent variable. In the first study 6- and 8-year-old children memorized the following sentence: “John likes to feed the little puppies in the barn.” Their response times suggested that the dominant segmentation pattern consisted of four phrases: a subject phrase, a verb phrase, an object phrase and a modifier phrase. Within each phrase differences between reaction times were on the order of 30 msec. Across phrases they were on the order of 120 msec. The same trend emerged for subsamples of the children with various short-term memory sizes, and for adults. It also appeared for subsamples of the total scores (e.g., first six trials and last six trials). In order to provide further evidence of the technique's validity, different sentences of the same general type were presented to children with short-term memory spans of either 3, 4, or 5. As predicted, it was found that when children's spans corresponded to the number of hypothesized chunks (i.e., 4), they could repeat the sentences verbatim on the first exposure. They could not do so, however, when their spans were lower than that value or when the number of phrases was increased. It was concluded that the new technique is a promising one for assessing young children's patterns of speech segmentation.     

Satiation for social reinforcers: The effects of contingency,vicarious experience,and ambiguous situations

The relative satiation effect, an inverse relationship between the frequency of prior social reinforcement (the word “good”) and the later effectiveness of the social reinforcer in controlling behavior, was studied. In Experiment 1, a discrimination task in which social reinforcement was given for correct responses was administered to first- to fourth-grade children (6 to 10 years of age), who had during a preexposure phase performed a preliminary task or observed another child performing. During the preexposure phase, the experimenter delivered frequent or infrequent social reinforcement that was either contingent or noncontingent. Only performers and observers who had experienced frequent noncontingent reinforcement showed the satiation effect during the discrimination task phase. The results were interpreted as inconsistent with J. L. Gewirtz' (Developmental Psychology, 1969, 1, 2–13) social drive formulation but supportive of an informational analysis in which the children are seen as responding appropriately to unambiguous evidence concerning the reliability of contingency information. In Experiment 2, seating arrangements were varied so that information concerning the direction of reinforcement was made ambiguous. Performers were less responsive during the discrimination phase after experiencing frequent noncontingent reinforcement when seated alone or opposite an observer than when seated next to an observer. The results are interpreted as indicating trust of the reliability of the contingency under ambiguous conditions.     

Development of comprehension of sentences with “because” or “if”

The comprehension of sentences with “because” or “if” was investigated in children aged 2;9–11;11. Imitation, comprehension (choosing one of two picture sequences to go with a sentence), recognition (judging sentences with connective or structure differences as heard before or not), and synonymy (judging equivalence of meaning in sentences with different connectives or structures) tasks were administered, along with logical ordering, reversibility, and classification tasks. Above-chance responding in the comprehension task occurred by age 8, and in recognition and synonymy by age 10. Cognitive performance predicted 28.4% of the variance in the linguistic scores and cognitive success was concurrent with or preceded linguistic success. Comprehension of “because” and “if” appears to develop gradually, and is related to the development of certain operative rules.     

On knowing how well one is remembering: The persistence of strategy use during transfer

A potential cause for children's failure to transfer learning strategies was explored in the present study. A self-monitoring process was suggested to be essential for evaluating one's own level of performance and the effectiveness of various mnemonic strategies. Matched on free recall scores in this study's first sort-and-recall phase, first, third, and fifth graders (ages 7, 9, and 11 years, respectively) were assigned to one of three treatment groups or a control group. During Phase II, the treatment groups received instruction in sorting pictures according to semantic similarities in preparation for future recall. In addition, Groups 3 and 4 later received feedback indicating their Phase II improvement in performance. A cause-and-effect relationship between strategy use and enhanced recall was further suggested to Group 4. Among third graders, only those provided with feedback and strategy instruction continued to rely upon the input organization strategy when faced with transfer tasks in Phase III. Both enhanced recall and improved sorting styles were observed for these subjects in Phase III. Some first graders also showed improved sorting styles and improved recall following feedback, while fifth graders showed enhanced recall even without experimenter-provided feedback. Subject's responses to a metamemory interview provided additional support for the hypothesis that the self-monitoring of memory performance is more likely to be part of fifth graders' (than first graders') memory abilities.     

Is knowledge base development a necessary and sufficient condition for memory development?

The hypothesis that knowledge base development is an important condition for memory development was tested in two experiments. In Experiment 1 subjects from grades K, 6, and college participated in an incidental learning task where they analyzed words according to one of four featural systems: physical, acoustic, semantic, and imagery. Large developmental differences in recall were found in the imagery and semantic conditions, small differences were observed in the acoustic conditions, and no developmental differences were found in the physical condition. Experiment 2 involved presenting college students and third graders words either from categories highly salient to third graders, e.g., cartoons, games, etc., or from corresponding Battig and Montague categories generated by college students. Free recall and clustering performances showed significant interactions, with third graders superior on the third-grade salient items, and college students superior on Battig and Montague items.     

Maintenance and generalization of a semantic rehearsal strategy in educable mentally retarded children

Two groups of 11- to 12-year-old educable mentally retarded children, equated on the basis of a free recall pretest, were given a series of lists for free recall. Approximately half the subjects were trained in the use of a strategy designed to induce deeper level semantic encoding and the discovery of categorical relationships and half constituted a “no-training” control group with standard free recall instructions. The subjects received either related or unrelated lists during the training phase and related or unrelated lists during two post-tests, immediately following and 1 week after training. There was evidence not only that the semantic strategy was maintained over the 1-week delay, but that it also generalized to word lists unlike those used during training. The degree of generalization was greater for those subjects receiving related lists during training.     

Developmental trends in distractibility: Is absolute or proportional decrement the appropriate measure of interference?

Since baseline performance varies with age, diminished interference effects found with increasing age do not provide evidence for a developmental trend in distractibility unless their relationship to baseline performance is known. In the present study, baseline difficulty was varied in two speeded classification experiments to investigate whether interference effects due to irrelevant information could best be characterized by absolute or proportional decrement models. In Experiment 1, first graders, third graders, and adults sorted cards on the basis of square size, both in the presence and absence of extraneous stimulus information. In Experiment 2, first graders and adults sorted cards on the basis of the density of a regular array of dots and two kinds of irrelevant information were used. Robust interference effects were found which declined with age. Manipulating discriminability of the relevant stimulus dimension resulted in large changes in sorting time, but interference effects did not vary with baseline difficulty. These results were interpreted as strongly supporting both an absolute decrement model and a developmental trend in distractibility.