Qualities of memories for performed and imagined actions

When people imagine performing simple actions they can sometimes become confused about whether they actually performed the actions or only imagined doing so. In the present study participants performed, imagined, and heard groups of actions. During a second session participants imagined some of the earlier actions as well as some entirely new actions. On a later memory test participants sometimes falsely indicated that they had performed actions that they had only imagined and this tendency was a positive function of number of imaginings. We also found that true and false memories differed in terms of degree of perceptual detail, associated thoughts, emotions, contextual information, and kinesthetic detail. Differences between true and false memories were smaller when the action was imagined five times but were not entirely eliminated. These findings suggest that false memories produced in this paradigm can be both compelling and yet subtly different from true memories. Copyright © 2003 John Wiley & Sons, Ltd.     

Developmental and individual differences in preschoolers' recognition memories: The influences of gender schematization and verbal labeling of information

Eighty-three 37-92-month-old children's gender schematization and recognition memories for gender-typed content were assessed. Verbal labeling of stimuli and age were positively associated with children's memories. Highly gender schematic children displayed better memories for gender-role consistent information and committed more gender transformation errors than less gender schematic children. Interactions between children's gender schematization, age, and labeling condition were observed. Labeling of stimuli facilitated less schematic children's memories for gender-role consistent information. Gender schematization was positively associated with younger children's memories, suggesting younger children's memories are more strongly mediated by gender schematization than older children's. Results support the position that studies of gender schema development require an integrated approach recognizing individual and developmental differences in gender schematic processing.Completion of this project was facilitated by funds received while the author was a National Institute of Mental Health Postdoctoral Fellow at the University of Denver: Grant 5T32 MH 15780-09. This support is gratefully acknowledged. An earlier version of this paper was presented at the Conference on Human Development, Charleston, South Carolina, 1988. The author would like to thank the faculty and staff of the Tiny Tot, Jack & Jill, Little Learners II, Plymouth and Upstate preschools for their assistance and cooperation. The author wishes to recognize James Aber, Rosanne David, Melisa Shack, and Susan Zigelbaum for their exceptional service in conducting the project; and would also like to thank Joan Barth, D. Bruce Carter, Gail S. Goodman, Carol L. Martin, William J. Meyer, Kathy Park, Ralph J. Roberts, Jaipaul L. Roopnarine, Margaret L. Signorella, and the anonymous reviewers for their comments and suggestions on earlier drafts of this article.     

Developmental and sex-related differences in preschoolers' affective decision making

This study investigated developmental and sex-related differences in affective decision making, using a two-deck version of Children's Gambling Task administered to 3- and 4-year-old children. The main findings were that 4-year-old children displayed better decision-making performance than 3-year-olds. This effect was independent of developmental changes in inductive reasoning, language, and working memory. There were also sex differences in decision-making performance, which were apparent only in 3-year-old children and favored girls. Moreover, age predicted awareness of task and the correlation between the latter and decision-making performance was significant, but only in 4-year-old children. This study thus indicates that there is a remarkable developmental leap in affective decision making, whose effects are apparent around the age of 4, which according to our results, also marks the age when the correlation of declarative knowledge and decision-making performance becomes significant.     

When Baby Maisy came to school: Mothers' interview styles and preschoolers' event memories

Fifteen 4–5-year-old children experienced a surprise event in their classroom — the visit of their former teacher and her new baby. The same day, children were interviewed about the event by their mothers, who had not been present and were naive to details. Mothers questioned their children in whatever way they wished. Three weeks later, children were interviewed by a researcher who had not been present during the original event and who had no information about the content of the parent–child interviews. Results showed that mothers' conversational style predicted the amount of information children provided during the mother–child interview, which in turn predicted how much accurate information children remembered during the researcher–child interview. The findings suggest that parent–child memory talk affects children's long-term memory reports, even when parents do not share in the event and have no knowledge of its details.     

Developmental changes in the discrimination of dynamic human actions in infancy

Recent evidence suggests that adults selectively attend to features of action, such as how a hand contacts an object, and less to configural properties of action, such as spatial trajectory, when observing human actions. The current research investigated whether this bias develops in infancy. We utilized a habituation paradigm to assess 4-month-old and 10-month-old infants' discrimination of action based on featural, configural, and temporal sources of action information. Younger infants were able to discriminate changes to all three sources of information, but older infants were only able to reliably discriminate changes to featural information. These results highlight a previously unknown aspect of early action processing, and suggest that action perception may undergo a developmental process akin to perceptual narrowing.     

Aging and qualitative characteristics of memories for perceived and imagined complex events

Older and younger adults' memory for perceived and imagined events was examined with a procedure in which everyday situations are simulated in the laboratory. Subjects perceived some situations and imagined others. Later, they were asked to rate their memory for various aspects of these situations (e.g., amount of perceptual detail, thoughts and feelings). A recall test followed the ratings. On the rating scale, for both perceived and imagined events, older subjects reported better memory for their thoughts and feelings than did younger subjects. In addition, on the recall test, older subjects produced more thoughts and feelings than did younger subjects, whereas younger subjects produced more perceptual and spatial information. These results suggest that older subjects may not inhibit personal information (e.g., thoughts and feelings), and this information may interfere with memory for other aspects of information, such as perceptual and contextual details (Hasher & Zacks, 1988).     

Loving-kindness language exposure leads to changes in sensitivity to imagined pain

To better understand the cultivation of positive intra- and interpersonal emotions, we examined an argument that some effects of contemplative training result from language processing. We presented participants with loving-kindness language used in kindness-meditation training studies and asked them to rate imagined pain. If loving-kindness language processing is responsible for some effects recently reported we expected this language could affect intra- and interpersonal sensitivity. Loving-kindness-language participants rated imagined other-pain significantly higher and imagined self-pain significantly lower than closely matched control participants. As a result of this interaction, the loving-kindness-language group showed no significant difference between self-pain and other-pain, whereas controls rated self-pain significantly higher than other-pain. These results suggest that exposure to loving-kindness-language in Loving-Kindness Meditation leads to changes in sensitivity to own and vicarious distress without explicit training. These findings underscore that meditation-like effects may be easily induced. Further research is needed to determine duration and degree of effect.     

The reminiscence bump without memories: The distribution of imagined word-cued and important autobiographical memories in a hypothetical 70-year-old

The reminiscence bump is the disproportionate number of autobiographical memories dating from adolescence and early adulthood. It has often been ascribed to a consolidation of the mature self in the period covered by the bump. Here we stripped away factors relating to the characteristics of autobiographical memories per se, most notably factors that aid in their encoding or retention, by asking students to generate imagined word-cued and imagined ‘most important’ autobiographical memories of a hypothetical, prototypical 70-year-old of their own culture and gender. We compared the distribution of these fictional memories with the distributions of actual word-cued and most important autobiographical memories in a sample of 61–70-year-olds. We found a striking similarity between the temporal distributions of the imagined memories and the actual memories. These results suggest that the reminiscence bump is largely driven by constructive, schematic factors at retrieval, thereby challenging most existing theoretical accounts.     

Reality monitoring of performed and imagined interactive events: developmental and contextual effects

Age differences in reality monitoring of interactive events were examined among 4-year-olds, 8-year-olds, 12-year-olds, and adults. Participants engaged in some interactions and imagined others. Afterward, they were asked to determine whether each action was performed, imagined, or new. This memory test was repeated 1 week later. The 4-year-olds had more difficulty discriminating imagined actions than the two oldest age groups. Imagined actions were more often confused with performed ones than the reverse, though this bias was significant only for the two younger age groups. Reality monitoring decreased over time, especially for imagined items. Activities in which the participant was the agent of action were discriminated better than those in which someone else was the agent of action. Object use during the activity increased the discrimination of imagined actions, especially after the delay. Similarity among actions had no effect. Implications for child eyewitness testimony are discussed.     

Effects of token variability on our ability to distinguish between vowels

Even when the speaker, context, and speaking style are held fixed, the physical properties of naturally spoken utterances of the same speech sound vary considerably. This variability imposes limits on our ability to distinguish between different speech sounds. We present a conceptual framework for relating the ability to distinguish between speech sounds in single-token experiments (in which each speech sound is represented by a single wave form) to resolution in multiple-token experiments. Experimental results indicate that this ability is substantially reduced by an increase in the number of tokens from 1 to 4, but that there is little further reduction when the number of tokens increases to 16. Furthermore, although there is little relation between the ability to distinguish between a given pair of tokens in the multiple- and the 1-token experiments, there is a modest correlation between the ability to distinguish specific vowel tokens in the 4- and 16-token experiments. These results suggest that while listeners use a multiplicity of cues to distinguish between single tokens of a pair of vowel sounds, so that performance is highly variable both across tokens and listeners, they use a smaller set when distinguishing between populations of naturally produced vowel tokens, so that variability is reduced. The effectiveness of the cues used in the latter case is limited more by internal noise than by the variability of the cues themselves.     

Children's ability to distinguish between enjoyment and non‐enjoyment smiles

Children's ability to distinguish between enjoyment and non‐enjoyment smiles was investigated by presenting participants with short video excerpts of smiles. Enjoyment smiles differed from non‐enjoyment smiles by greater symmetry and by appearance changes produced in the eye region by the Cheek Raiser action. The results indicate that 6‐ and 7‐year‐old children have the abilities to detect these differences and are able to interpret them with above chance‐level accuracy. Sensitivity was higher for the symmetry of the smiles than for the appearance changes produced in the eye region and improved in later childhood. Copyright © 2009 John Wiley & Sons, Ltd.     

Retrieval-induced forgetting of performed and observed bizarre and familiar actions

To investigate whether people show retrieval-induced forgetting (RIF) for bizarre and familiar actions that they performed or observed, three experiments were conducted. In Experiment 1, participants performed bizarre and familiar actions with different objects during learning (e.g., pencil: balance the pencil across the cup, sharpen the pencil). They repeatedly performed a set of the bizarre or familiar actions during retrieval practice. After a distracter task, participants' cued recall was tested. Participants showed RIF for both bizarre and familiar actions. In Experiment 2, half of the participants performed the bizarre and familiar actions themselves; the other half observed the experimenter performing the actions. Replicating the results of Experiment 1, participants who performed the actions showed RIF for bizarre and familiar actions. In contrast, participants who observed the actions did not show RIF for either action type. Experiment 3 examined whether this lack of RIF for observed actions occurred due to a lack of active recall during retrieval practice; it did. Overall, the three experiments demonstrated RIF for both bizarre and familiar performed and observed actions. A distinctiveness account of the results is provided.     

Opposite actions of dopamine on aversive and appetitive memories in the crab

The understanding of how the reinforcement is represented in the central nervous system during memory formation is a current issue in neurobiology. Several studies in insects provide evidence of the instructive role of biogenic amines during the learning and memory process. In insects it was widely accepted that dopamine (DA) mediates aversive reinforcements. However, the idea of DA being exclusively involved in aversive memory has been challenged in recent studies. Here, we study the involvement of DA during aversive and appetitive memories in the crab Chasmagnathus. We found that DA-receptor antagonists impair aversive memory consolidation, in agreement with previous reports in insects, while administration of DA facilitates memory formation after a weak training protocol. In contrast, DA treatment during appetitive training was found to impair formation of long-term appetitive memory. In addition, as a first step in elucidating the neuroanatomical correlates of DA action on memory, we mapped dopaminergic neurons in the central nervous system of the crab. Results of the current study, together with those obtained in a previous work about the role of octopamine (OA), suggest that both amines (DA and OA) play a dual action in memory processes. On the one hand, DA and OA mediate the aversive and the appetitive signals, respectively, throughout training, while on the other hand, they interfere with the formation of memory of the opposite sign (DA in appetitive and OA in aversive). Our results support a new understanding about the way appetitive and aversive stimuli are processed during memory formation to ensure adaptive behavior.     

Developmental changes in sensitivity to vocal paralanguage

Developmental changes in children’s sensitivity to the role of acoustic variation in the speech stream in conveying speaker affect (vocal paralanguage) were examined. Four‐, 7‐ and 10‐year‐olds heard utterances in three formats: low‐pass filtered, reiterant, and normal speech. The availability of lexical and paralinguistic information varied across these three formats in a way that required children to base their judgments of speaker affect on different configurations of cues in each format. Across ages, the best performance was obtained when a rich array of acoustic cues was present and when there was no competing lexical information. Four‐year‐olds performed at chance when judgments had to be based solely on speech prosody in the filtered format and they were unable to selectively attend to paralanguage when discrepant lexical cues were present in normal speech. Seven‐year‐olds were significantly more sensitive to the paralinguistic role of speech prosody in filtered speech than were 4‐year‐olds and there was a trend toward greater attention to paralanguage when lexical and paralinguistic cues were inconsistent in normal speech. An integration of the ability to utilize prosodic cues to speaker affect with attention to paralanguage in cases of lexical/paralinguistic discrepancy was observed for 10‐year‐olds. The results are discussed in terms of the development of a perceptual bias emerging out of selective attention to language.     

Phenomenal characteristics of autobiographical memories and imagined events in sub‐clinical obsessive‐compulsive checkers

Phenomenal characteristics of autobiographical memories and imagined experiences were examined in checking‐ and non‐checking‐prone individuals. Participants were asked to retrieve a positive, a negative and a neutral memory, and to imagine a positive, a negative and a neutral experience. They were then requested to evaluate each event according to characteristics such as sensory and contextual details. The main results revealed that non‐checking‐prone participants reported more general vividness than checking‐prone individuals for real events. In addition, non‐checking‐prone individuals reported more visual details and vividness for real than imagined experiences, while no difference between real and imagined events was found for checking‐prone participants. These results suggest that checking‐prone participants report poor memories of real events, which could in turn explain their difficulties distinguishing between real and imagined events. Copyright © 2007 John Wiley & Sons, Ltd.     

Developmental changes in response preparation to visual stimuli

We examined how preparation to respond changes with age. Subjects from four age groups (5- to 7-, 8- to 11-, 12- to 17-, and 18- to 24-yr.-olds) were given a simple visual RT task with foreperiod duration varied between 300 and 2000 msec. Analysis showed that in addition to the expected effects of age and foreperiod, there were qualitative differences between the performance of adults and children: 5- to 7-yr.-olds reacted quickest after a foreperiod shorter than that required by adults to perform best. Conversely, preadolescents' optimal foreperiod was relatively longer than that of either older or younger subjects. In addition, the youngest subjects showed an inability to maintain preparation as efficiently as older subjects. Implications for the development of response preparation are discussed.     

Developmental changes in neural activity to familiar words and gestures

Infants younger than 20 months of age interpret both words and symbolic gestures as object names. Later in development words and gestures take on divergent communicative functions. Here, we examined patterns of brain activity to words and gestures in typically developing infants at 18 and 26 months of age. Event-related potentials (ERPs) were recorded during a match/mismatch task. At 18 months, an N400 mismatch effect was observed for pictures preceded by both words and gestures. At 26 months the N400 effect was limited to words. The results provide the first neurobiological evidence showing developmental changes in semantic processing of gestures.