The facilitation of long-term memory improvement and operative development.

J. Piaget and B. Inhelder (1973) have reported that children's memories for pictures or events improve between early (1-wk) and late (several-month) recall sessions in conjunction with operative growth. Using the concept of verticality, the present study investigated (a) if an intervening operative training task would increase memory improvements, and (b) if exposure to the memory stimulus per se would enhance later operative performance. 97 3rd graders were randomly assigned to 1 of 4 groups—with or without operative training and with or without a memory task. At the end of the school year, all Ss were tested for operative level. The trained group showed significantly more memory progressions and fewer regressions than the untrained group on 1 of 2 memory stimuli. On the 2nd stimulus, performance was consistently high across children and recall sessions, and thus no differences were found as a function of training. Participation in the memory task enhanced later operative performance. Implications for Piagetian memory research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Implicit learning and generalization of the "mere exposure" effect.

Reports 2 experiments that examined the generalization of the "mere exposure" effect. Both experiments demonstrated that positive affect, produced by repeated viewing of a set of stimuli, generalizes to previously unseen stimuli that are similar to the exposed stimuli along certain abstract dimensions. Exp I, with 82 Ss, used letter strings constructed according to a complex rule system. Positive affect attributable to exposure generalized to novel letter strings that obeyed the rule system. Affective generalization was related to Ss' judgments of whether the novel strings obeyed the rule system. Exp II (40 Ss), in which the stimuli were complex visual patterns created by distorting standard forms, yielded an orderly gradient of affective generalization to novel patterns at varying levels of distortion. Results indicate that the exposure effect behaves in a manner similar to "implicit" concept learning and rule induction. The generalization techniques developed here provide a novel method for studying the affective processing of stimuli. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The ontogeny of feeding in rats: III. Thermal determinants of early ingestive responding.

High ambient temperatures (38°C) stimulated high spontaneous levels of activity and high frequencies of behaviors normally associated with ingestion (mouthing and probing), particularly in young, 3- and 6-day-old Charles River CD rat pups (Exp I). The level of spontaneous behavior was highly correlated with body temperature and also depended on deprivation condition. Temperature played an important role in determining responses to food stimuli as well. When Ss were fed by oral infusion (Exp II) or by placing milk on the floor beneath them (Exp III), warm ambient temperatures were required for active ingestion. In Exp IV, body temperature and ambient temperature were manipulated independently to assess their relative importance for Ss' feeding behavior. Ss with a low (29°C) or normal (34°C) core temperature at the start of testing were fed in either a 24°C or a 34°C ambience. Regardless of body temperature, Ss' levels of intake, activity, mouthing, and probing were higher in a warm than in a cool ambience. Therefore, the suppressed ingestive behavior of Ss fed at cool temperatures occurred not simply because Ss became hypothermic and inactive. Perceived warmth appears to be a significant contextual cue that regulates pups' responses to food stimuli. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Seeing versus imagining movement in depth.

Six undergraduate students participated in 2 experiments to determine whether the same mechanisms are activated during perception of real vs apparent motion. In Exp 1, Ss judged the quality of rigid motion between pairs of 3-dimensional drawings that differed by a rotation in depth. Rated quality of motion decreased with increasing angular disparity between the figures and with decreasing stimulus duration, regardless of whether the figures were vertical or oblique. In Exp 2, Ss participated in a mental rotation task using the same stimuli and angular disparities. Ss took longer to make decisions about obliquely aligned than vertically aligned stimuli. Results imply that perceived vs imagined movement through the same trajectory involves different processes. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Impact of group consensus and social support on stimulus meaning: Mediation of conformity by cognitive restructuring.

Three experiments with a total of 163 undergraduates tested the hypothesis that a person reinterprets the meaning of the stimulus object when facing unpopular responses from a unanimous group and that this change in meaning leads to a shift in response toward the group's position. In Exp I, several opinion items were presented, and either Ss observed unpopular responses, supposedly made earlier by a unanimous group (UG) or by a group having 1 dissenter (social support), or they observed no response at all (control). Ss merely gave their interpretation of the meaning of a key word or phrase in each opinion statement—they did not give their own opinions. Results show that UG Ss gave more uncommon meanings to the stimuli than did Ss in the other 2 conditions. Exp II ruled out the possibility that the shift in meaning was due to Ss' adhering to the interpretation they assumed to be held by the majority. In Exp III, Ss were exposed to scores representing the meanings that were produced by the unanimous group and control conditions in Exp I. Results show that after observing the consensually produced meanings for these items, the Ss shifted their own opinions toward the position held by the UG in Exp I. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Do the same stimulus-response relations influence choice reactions initially and after practice?

A 2-choice reaction task was used to evaluate changes in stimulus–response translation with practice. In Exp 1, 4 groups of Ss practiced with either a direct or indirect mapping of left–right stimuli to left–right responses and either a crossed or uncrossed hand placement and transferred to 1 of the 4 Mapping?×?Placement conditions. Stimulus–response location and response location effector relations affected performance initially and after practice. In Exps 2 and 3, Ss switched every 42 trials between conditions for which only the stimulus location–effector (Exp 2) or stimulus–response location relation (Exp 3) remained constant. Switching produced interference in Exp 2 but not in Exp 3, corroborating the influence of the stimulus–response location relation on performance. Mediation based on spatial codes continues to be a factor in the performance of practiced Ss. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Memory for pictures: Does an age-related decline exist?

Examined the effects of varying detail on memory. In Exp I, pictorial embellishment was varied by presenting 27 Ss aged 60+ yrs and 30 undergraduates with normal photographs, high-contrast photographs, or line drawings, and testing their memory immediately and 4 wks later. All of the Ss did best with the most elaborate pictures (normal photographs), and old Ss remembered as well as young at the immediate but not at the delayed interval. In Exp II, with 21 old Ss and 21 18–36 yr olds, detail was varied by adding background to line drawings of a central object. Ss of both ages profited from enhanced background detail, and there were no differences in memory as a function of age. Exp III replicated Exp II, except that Ss (10 elderly and 17 college students) studied the pictures under divided attention conditions. Again, Ss of both ages recognized elaborate pictures best, and no significant age differences emerged. Results suggest that old and young adults profit from visual embellishment and that memory for meaningful pictures remains relatively intact with age. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The operative basis of performance on Piagetian memory tasks: Evidence from normal and learning disabled children.

Investigated the role of operative schemes in explaining older children's superior memory on past Piagetian memory tasks. In Exp I, 60 1st–4th grade concrete operational children—half with deficits in visual memory (learning disabled, LD)—reconstructed 2 stimuli in which operative schemes were or were not relevant (a seriated array vs an arbitrary color sequence). As predicted, LD children performed significantly worse than normals on the arbitrary stimulus only. Exp II tested whether this difference resulted simply from differential task difficulty. 28 preschoolers who either could or could not seriate reconstructed both stimuli. Only seriaters performed significantly better on the operative stimulus than on the arbitrary stimulus, supporting the Piagetian position. (2 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Scheme and schema in children's memory of their own drawings.

4 groups of 78 6-yr-old children made drawings of 6 themes. One month later new drawings of the same themes were made by the same Ss under 4 conditions: free drawing, memory of the 1st drawing, making a copy of the 1st drawing, making a drawing that appeared different from the 1st one. A week later the Ss were tested for recognition of their own drawings and identification as to when they had been drawn. Recognition of 2nd-session drawings was about equal among the 4 conditions, even though order identification varied significantly and adults found perceptual matches of drawings from the same S much easier with the copy than with the different condition. Results support Piaget's scheme-schema memory distinction in that a basic operative scheme lies behind alternative figural representations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of children's understanding of the metalinguistic term word..

Designed 3 experiments to assess 24 preschool (mean age 64.63 mo), 24 1st-grade (mean age 76.25 mo), and 24 2nd grade (mean age 88.61 mo) children's understanding of the term word. A modified aural discrimination task was used in which Ss were required to discriminate word from nonword stimuli along only 1 dimension at a time. Exp I tested Ss' discrimination of words and sounds. Exp II examined word–phrase differentiation. Both of these experiments followed previous research in examining children's comprehension of the term word in relation to nouns. Exp III examined Ss' understanding of word with stimuli from a variety of form classes. Results indicate that Ss' word concepts have been underestimated in past research suggesting that young children lack an adequate word concept: although preschool Ss did not understand the term properly, by 1st grade word was understood. These experiments also show that Ss benefited from brief training in which they were taught to attach the metalinguistic label word to their developing concept of the word as a unit of spoken language. (38 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Visual sampling after lesions of the superior colliculus in rats.

In 2 experiments with 20 male black-hooded rats, Ss with bilateral lesions of the superior colliculus showed significantly poorer relearning of a horizontal/vertical stripe discrimination than control Ss. In Exp I, all Ss showed disruption of performance when a stimulus–response (S–R) separation was introduced by raising the stimuli above the site of responding. However, colliculectomized Ss were much more disturbed by the S–R separation than were control Ss. In Exp II, all Ss showed lower performance levels when conflicting patterns were introduced into the upper portion of the stimulus doors, but this time Ss with collicular lesions were less disturbed than controls. It is suggested (a) that when the stimulus and response sites are discontinuous, rats must make an appropriate orienting response to effectively sample the visual stimuli and (b) that lesions of the superior colliculus alter performance by interfering with this orienting behavior. The impairment in relearning is attributed to the absence of preoperative overtraining on the discrimination task. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cross-modal transfer in 6-month-old infants.

Investigated in 4 studies with 101 infants 25.5–32 wks of age the ability of Ss to transfer information about shape across modalities. Ss were familiarized either orally or tactually and then tested for visual recognition memory. In Exp I, Ss failed to show evidence of cross-modal transfer on any of the tasks (1 oral–visual, 2 tactual–visual). When familiarization times were increased from 30 to 60 sec in Exp II, Ss showed evidence of transfer on both tactual–visual tasks. Exp III eliminated the 5–7 sec delay that generally intervenes between the familiarization and test phase. Ss were permitted to retain the stimulus in their hand (or mouth) during the test phase while simultaneously viewing a novel stimulus and a duplicate of the familiar stimulus. This modification resulted in successful transfer on 1 of the 2 tactual–visual tasks. Ss did not show evidence of transfer on the oral–visual problem in any of these studies, despite evidence from Exp IV that they could visually discriminate the paired stimuli used in these tasks and that they showed recognition memory when familiarization and testing were both visual. Results suggest that, although cross-modal transfer of information about shape is present among 6-mo-olds, it is a less robust phenomenon than that seen in older infants. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Emerging attributes in monkey short-term memory.

Conducted 2 experiments to examine the role of recency information and stimulus novelty and familiarity in delayed-matching-to-sample (DMTS) performance. Five female 5–8 yr old macaques (one of which was not included in Exp II) were tested on DMTS problems in which the correct and incorrect choice stimuli were both familiar, both relatively novel, or different in familiarity. Initially, novelty and familiarity exerted their influence as preferences (familiar stimuli were preferred). As more training was given, however, novelty and familiarity began to act as discriminative attributes. For example, Ss came to use the fact that the to-be-remembered stimulus was relatively novel to reject alternative choice stimuli that were more familiar. Theories of animal memory based on a single memory attribute cannot address these results. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Implicit stereotyping in person judgment.

Three experiments demonstrated implicit gender stereotyping. A target's social category determined the use of previously primed stereotyped information, without Ss' awareness of such influence. After unscrambling sentences describing neutral or stereotyped behaviors about dependence or aggression, Ss evaluated a female or male target. Although ratings of female and male targets did not differ after exposure to neutral primes, Ss exposed to dependence primes rated a female target as more dependent than a male target who performed identical behaviors (Exp 1A). Likewise, Ss rated a male, but not a female, target as more aggressive after exposure to aggression primes compared with neutral primes (Exp 1B). Exp 2 replicated the implicit stereotyping effect and additionally showed no relationship between explicit memory for primes and judgment of target's dependence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Face recognition accuracy as a function of mode of representation.

The relative effectiveness of line drawings and photographs as ways of representing information in face reconstruction systems was compared in 2 experiments. In Exp I, 3 independent groups of college students (27 in each group) were required to identify well-known faces shown either as photographs, detailed line drawings, or outline drawings. Photographs were significantly more effective as stimuli than line drawings, which in turn were superior to outlines. In Exp II, 80 Ss aged 16–60 yrs recruited from the public participated in a recognition task. Photographs and detailed line drawings of previously unknown faces served as stimuli. Ss recognized photographs significantly more accurately than line drawings, even when the pose of the target was changed between the exposure and test series. Results are discussed in terms of the development of computer-based face reconstruction systems and theories of face recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The formation of stereotypic beliefs: Further evidence for distinctiveness-based illusory correlations.

Investigated the processes underlying illusory correlations based on the co-occurrence of infrequent stimulus events in 2 experiments with 104 undergraduates. In Exp I, 4 groups of 20 Ss were assigned to 1 of 4 conditions. Group 1 read a series of stimulus sentences describing desirable and undesirable behaviors performed by members of Groups A and B. Group 2 read the same sentences but had a different order of presentation. Group 3 read the sentences and were shown a frequency table summarizing the information they had just read. Group 4 was given only the summary table showing the frequency distribution of desirable and undesirable behaviors for Groups A and B and asked to imagine that they had read sentences. Analysis of Ss' ratings showed that the bias producing the illusory correlation occurred during the encoding of serially presented stimulus items and was not due to biased integration of information at the time of judgment. In Exp II, 24 Ss were used to assess recall of stimulus information. Results show that Ss recalled a higher proportion of items representing the co-occurrence of distinctive stimuli than of the other categories of items. The central role of these items in establishing the illusory correlations was further substantiated by correlational evidence. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Testing models of delayed sequence discrimination in pigeons: The advance key procedure.

In 2-event delayed sequence discrimination (DSD) training, one arrangement (temporal order) of 2 sample stimuli is the positive sequence and the remaining are the negative sequences for keypecking during a subsequent test stimulus. Three models of the DSD task were tested in 2 experiments with 8 White Carneaux pigeons. In Exp I Ss were allowed to terminate a trial by pecking the "advance key" during the sample stimuli or to let the test stimulus progress to the next trial. In the absence of a peck to the advance key, the trial continued to the completion of the test stimulus. In Exp II, Ss were forced to choose actively between advancing to the next trial and continuing through the current trial. Choice between the advance and continue keys was required with the occurrence of each of the successive sample stimuli and the test stimulus. Although the addition of forced choice resulted in more uniform effects, Ss were able to identify negative sample sequences with the occurrence of the 1st negative sample event in both experiments. Results support the prospective memory model but not the retrospective and hybrid models of temporal sequence recognition in the 2-event DSD task. (French abstract) (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Acquired equivalence and distinctiveness in matching to sample by pigeons: Mediation by reinforcer-specific expectancies.

Assessed the ability of a reinforcer to mediate an association between 2 stimuli that independently predict the occurrence of that reinforcer (acquired equivalence of cues). In Exp I, 12 male White Carneaux pigeons were trained on shape (plus and circle) and color (red and green) matching-to-sample tasks. Correct responses were systematically reinforced with corn on some trials and wheat on others to establish associations between 1 stimulus from each task and a "common" outcome. Following training, Ss were transferred to a symbolic matching-to-sample task wherein a stimulus from one training task was presented as the sample, and the stimuli from the other training task were presented as comparisons. In the 1st session, experimental Ss made significantly more correct responses than controls (i.e., Ss "matched" stimuli previously associated with a common outcome). Exp II with 18 Ss replicated this acquired equivalence effect and controlled for food preference. Delayed matching-to-sample training demonstrated enhanced memory performance for Ss exposed to different reinforcement contingencies, but this effect was confined to the shape task. Results indicate that a reinforcer can serve as the basis for organizing otherwise unpaired predictive cues in memory and that animals will selectively use differential expectancies as cues for solving complex discrimination tasks, depending on the difficulty of the discrimination. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)