Memory strategies used by young normal and retarded children in a directed forgetting paradigm

Two experiments were reported investigating the possibility that normal children (6- to 7-years old) and retarded children (9- to 10-years old) equated for immediate memory performance may not use effective strategies to eliminate interference from irrelevant information in memory. In both experiments a directed forgetting paradigm was used in which the children were presented with two sets of four pictures, and recalled only one set on each trial. On some trials, there was a cue to forget the first four and to remember only the last four pictures. In the first experiment both groups adopted a passive-active strategy in which the to-be-remembered items were processed actively only after a forget cue. Experiment 2 replicated this pattern of results. The use of sophisticated directed forgetting strategies seemed to be beyond the immediate abilities of these children. Two possible interpretations of the passive-active strategy were offered: (a) The strategy was an attempt to cope with the presence of occasionally irrelevant information and (b) The strategy was an attempt to cope with memory overload.     

Responding to a positive stimulus by “satiated” pigeons

Skinner (1938) found that rats given discrimination training (Phase I) and then reinforced to “satiation” for responses in the presence of the negative stimulus (S?) (Phase II), began to respond again when the positive stimulus (S+) was reintroduced (Phase III). Experiment I replicated Skinner's finding with pigeons, alternating S+ and S? presentations during Phase III. In Experiment II, Phase II was extended, and Phase III results were similar to those of Experiment I, demonstrating that the recovery of S+ responding could not be attributed to a lax Phase II satiation criterion. In Experiment III, a uniform schedule of reinforcement was maintained throughout the three phases, and results similar to those of Experiment I were found, indicating that renewed S+ responding was not due to the shift in schedule between phases. In Experiment IV, Phase I consisted of discrimination training with two positive stimuli (S+_s and S+_n), and Phase II consisted of reinforcement for responses in the presence of S? and S+_s. During Phase III, significantly more responding was found to S+_s and S+_n than to S?, but no difference in responding was found between the two positive stimuli. In Experiment V, Phase I consisted of simple discrimination training, and during Phase II, responses in the presence of both S? and a novel stimulus (So) were reinforced. During Phase III, significantly more responding was found to S+ than to either S? or So, with no difference found between S? and So responding. Renewed responding to S+ during Phase III in the present experiments is best explained by behavioral contrast developed during Phase I.     

Speech timing of grammatical categories

A series of experiments was performed to determine how the duration of a word spoken in a sentence is influenced by: (1) the grammatical category to which it belongs, and (2) the position of the word in a constituent. Experiment I contained Noun-Verb homophones (e.g. “I saw the coach…” — noun; “I saw him coach…” — verb), in sentences matched for phonetic environment and stress pattern. Results support the notion that Nouns are longer than Verbs in typical sentences. Experiment II, however, demonstrated that the duration of Noun-Verb homophones in matched clause-final position is approximately equal. Experiment III contained transitive and intransitive Verbs in matched sentences. The results of Experiments II and III provided support for a lengthening account based on constituent-final position, while ruling out an account based on a debatable deletion site. Results of Experiment IV generalized the account of constituent-final lengthening for Nouns and Verbs to additional major categories, by comparing the duration of the phrase-initial Adjective two with the phrase-final Adverb too. Finally, Experiment V tested the distinction between minor and major categories. Results demonstrated that the Preposition to is shorter than the Adjective two by approximately 50 percent. Taken in sum, these findings indicate that it is sufficient to make a binary distinction between major and minor categories for purposes of a theory of speech timing and speech synthesis. Durational effects traditionally ascribed to differences within the class of major categories can be accounted for solely in terms of constituent boundaries, already required in the theory to account for three other classes of phenomena.     

Alcoholic Korsakoff patients' retrieval from semantic memory

Alcoholic Korsakoff patients' rate of retrieval from semantic memory was investigated. It was found that their rate of retrieval from “lexical” semantic memory was nearly normal, but their rate of retrieval from “conceptual” semantic memory was impaired. In addition, an attempt to “prime” their lexical semantic memory by requesting the same category to be searched on adjacent trials met with failure. It was concluded that Korsakoff patients' lexical storage is probably organized normally, but their conceptual organization is not. Parallels with these patients' episodic memory impairments are discussed and possible interactions between episodic and semantic memory are proposed.     

A Vocational interest test minus sex bias

The Vocational Preference Inventory responses from 290 subjects (110 males and 180 females) were subjected to a Rasch item analysis, one of a class of latent trait models. After elimination of 22 items which did not fit the model, a sex-free form of the VPI was obtained. Group interest scale scores are presented for each of the Holland scales and data are produced which indicate that no violence was done to the Holland coding system.     

Quantification and semantic memory

Two models are considered for how people verify explicitly quantified sentences, such as All fathers are parents and Some fathers are parents. The models share the same second stage, but have different first-stage mechanisms. In the Predicate Intersection Model, suggested by Meyer (1970), the first stage involves a serial, self-terminating search among names of categories that intersect the predicate category. In the Feature Comparison Model (Smith, Shoben & Rips, 1974a), the first stage involves evaluating the overall relatedness between the subject and predicate categories by comparing their semantic features. To test the models, three reaction time experiments required subjects to verify statements quantified by Some or All. In the first experiment, the semantic relatedness of categories in false Some-statements was varied. Contrary to predictions of the Predicate Intersection Model, related categories increased reaction time for both true and false Some-statements. While the first experiment revealed that All-statements took longer to verify than comparable Some-statements, the second experiment demonstrated that the All-Some difference can be eliminated by presenting both statement types in the same block of trials, also disconfirming the Predicate Intersection Model. Finally, Experiment III examined the meaning of Some-statements in more detail by having subjects interpret the quantifier Some as “some but not all.” With this interpretation, Some-statements took longer to verify than All-statements. Overall the results support the Feature Comparison Model.     

Immediate and delayed recognition of visual stimuli in poor and normal readers.

The present study investigated the hypothesis that specific reading disability is attributable to inadequate visual memory. Previous research had demonstrated that poor readers sustain no basic dysfunction in visual perception, but there was need to evaluate the possibility that deficiencies in letter and word recognition result from disorder in long-term visual storage. Adopting a format employed in a previous study, randomly arranged Hebrew letters were presented to poor and normal readers unfamiliar with Hebrew, and both groups were asked to demonstrate retention for these stimuli on three separate occasions: immediately after initial presentation, 24 hours later and 6 months later. As a control measure, the performance of the non-Hebrew subjects was compared with that of normal readers familiar with Hebrew letters. It was found that retention in the non-Hebrew groups was equivalent under all of the temporal conditions, but the performance of both was poorer than the Hebrew groups under the immediate and 24-hour conditions. However, none of the reader groups differed in the case of retention after a 6-month delay period. It was concluded that deficient visual memory is an unlikely source of specific reading disability, and alternative explanations of the disorder were considered.