Bodily self and schizophrenia: The loss of implicit self-body knowledge

Schizophrenia spectrum has been associated with a disruption of the basic sense of self, which pertains, among others, the representation of one's own body. We investigated the impact of either implicit or explicit access to the representation of one's own body-effectors on bodily self-awareness, in first-episode schizophrenia (FES) patients and healthy controls (HCs). We contrasted their performance in an implicit self-recognition task (visual matching) and in an explicit self/other discrimination task. Both tasks employed participant's own and others' body-effectors. Concerning the implicit task, HCs were more accurate with their own than with others' body-effectors, whereas patients did not show such self-advantage. Regarding the explicit task, both groups did not exhibit a self-advantage, and patients showed a higher percentage of self-misattribution errors. Neither self/other nor implicit/explicit effects were found in both groups when processing inanimate-objects. We propose that FES patients suffer of a disturbed implicit sense of bodily self.     

Delayed self-recognition in 2.5-year-old children: Evidence of a restricted sense of self?

In two experiments, we explored whether 2.5-year-olds can use delayed video information to locate objects placed somewhere covertly after first being given pre-test video experience. Our findings revealed that children had little difficulty passing a surprise-object task, that is, a teddy bear hidden in a box that was placed behind the child and hence only visible in the delayed video. In contrast, the children did not pass the surprise-mark task or delayed self-recognition (DSR) task, even with pre-test video training. Similarly, delayed self-image experience and pre-test video training did not facilitate DSR performance in 2.5-year-olds. Children were also just as likely to fail a live video self-recognition task, suggesting that object-retrieval tasks pertaining to self using video information are difficult for children at this age. The findings are discussed in light of possible changes in representational capabilities; the implications for the development of a temporally extended self are also noted.     

Variability in the early development of visual self-recognition

A study was conducted to evaluate the (1) developmental course and (2) the temporal sequencing of visual (mirror, photo) and verbal (personal pronoun use) measures of self-recognition as well as the ability to locate a toy from its mirror image in relation to the child's own mirror image. A microgenetic approach was adopted to assess 10 toddlers biweekly between 15 and 23 months of age and for comparison, a cross-section of children tested once across the same age range. Longitudinal data indicated that visual self-recognition emerged gradually and showed wide variability in expression prior to becoming stable, a finding masked in the cross-sectional data where performance appeared to improve abruptly. Both cross-sectional and longitudinal data confirmed that mirror self-recognition was the earliest precursor of the indices of self-recognition to emerge followed by the use of personal pronouns and photo identification. Implications for the emergence and integration of the self are discussed.     

Capuchin monkeys (Cebus apella) respond to video images of themselves

Many studies have used mirror-image stimulation in attempts to find self-recognition in monkeys. However, very few studies have presented monkeys with video images of themselves; the present study is the first to do so with capuchin monkeys. Six tufted capuchin monkeys were individually exposed to live face-on and side-on video images of themselves (experimental Phase 1). Both video screens initially elicited considerable interest. Two adult males looked preferentially at their face-on image, whereas two adult females looked preferentially at their side-on image; the latter elicited lateral movements and head-cocking. Only males showed communicative facial expressions, which were directed towards the face-on screen. In Phase 2 monkeys discriminated between real-time, face-on images and identical images delayed by 1 s, with the adult females especially preferring real-time images. In this phase both screens elicited facial expressions, shown by all monkeys. In Phase 3 there was no evidence of discrimination between previously recorded video images of self and similar images of a familiar conspecific. Although they showed no signs of explicit self-recognition, the monkeys’ behaviour strongly suggests recognition of the correspondence between kinaesthetic information and external visual effects. In species such as humans and great apes, this type of self-awareness feeds into a system that gives rise to explicit self-recognition.     

No evidence for infants’ contingency detection as a precursor of toddlers’ self-recognition

The aim of the present study was to assess the relationship between infants’ contingency preference and detection in the first year of life and toddlers’ mirror and video self-recognition in the second and third year of life in a longitudinal study (N = 113). Six- and 9-month-olds’ preference for a noncontingent over a perfect contingent view (contingency preference) and their differentiation between the two views – indicated by longer looking times to either view – (contingency detection) were assessed in two contingency tasks. A mirror-face-recognition task and a mirror-leg-recognition task were conducted at 18 months. A video-face-recognition task and a mirror-leg-recognition task were conducted at 26 months. Results revealed no predictive relationships between infants’ contingency preference and detection in the first year of life and their ability to recognize themselves in a mirror or on a video monitor in the second and third year of life. This finding supports the notion that self-recognition emerges independently from the experience of contingencies (Bischof-Köhler, 1991, 2012). Thus, a representation of the self seems to rely on more than a specific developmental pathway leading from contingency preference and detection to self-recognition.     

Age-related changes in children's use of external representations.

This study explored children's use of external representations. Experiment 1 focused on representations of self: Self-recognition was assessed by a mark test as a function of age (3 vs. 4 years), delay (5 s vs. 3 min), and media (photographs vs. drawings). Four-year-olds outperformed 3-year-olds; children performed better with photographs than drawings; and there was no effect of delay. In Experiment 2, 3- and 4-year-olds used a delayed video image to locate a sticker on themselves (self task) or a stuffed animal (other task). The 2 tasks were positively correlated with age and vocabulary partialed out. Experiment 3 used a search task to assess whether children have particular difficulty using external representations that conflict with their expectations: 3- and 4-year-olds were informed of an object's location verbally or through video: on half of the trials, this information conflicted with children's initial belief. Three-year-olds performed worse than 4-year-olds on conflict trials, indicating that assessments of self and other understanding may reflect children's ability to reason about conflicting external representations.     

Lack of effort as a result of self-focused attention: An attributional ambiguity analysis

Attributional ambiguity is a strategy used to avoid having to attribute potentially negative performance on a task to ability. If the outcome of a task is attributable to ability, if no external cause for failure is available, and if a person is aware that the outcome is attributable to the self, ambiquity can be created with regard to the causation of the outcome. Heightened attribution of an outcome to self, as results from self-focused attention, was expected to produce less effort when external causes for potential failure were explicitly removed. In a 2 × 2 experiment, a positive mood was induced that was then either suggested or excluded as a plausible explanation for potential failure on a task said to be indicative of general intellectual ability. Subjects for whom self-awareness was experimentally induced, and for whom an external attribution of failure was explicitly removed, put significantly less effort into the task. Self-focus, however, has also been shown to enhance task performance. An indirect measure showed increased readiness to perform in direct contrast to the obtained lower self-reports of effort. The range of generalizability and application of attribute ambiguity is discussed.     

Does interference between self and other perspectives in theory of mind tasks reflect a common underlying process? Evidence from individual differences in theory of mind and inhibitory control

Theory of mind (ToM), the ability to understand that other agents have different beliefs, desires, and knowledge than oneself, has been extensively researched. Theory of mind tasks involve participants dealing with interference between their self-perspective and another agent’s perspective, and this interference has been related to executive function, particularly to inhibitory control. This study assessed whether there are individual differences in self–other interference, and whether these effects are due to individual differences in executive function. A total of 142 participants completed two ToM (the director task and a Level 1 visual perspective-taking task), which both involve self–other interference, and a battery of inhibitory control tasks. The relationships between the tasks were examined using path analysis. Results showed that the self–other interference effects of the two ToM tasks were dissociable, with individual differences in performance on the ToM tasks being unrelated and performance in each predicted by different inhibitory control tasks. We suggest that self–other differences are part of the nature of ToM tasks, but self–other interference is not a unitary construct. Instead, self–other differences result in interference effects in various ways and at different stages of processing, and these effects may not be a major limiting step for adults’ performance on typical ToM tasks. Further work is needed to assess other factors that may limit adults’ ToM performance and hence explain individual differences in social ability.

     

"When did I learn and when shall I act?": The developmental relationship between episodic future thinking and memory

This study investigated the development of the ability to reflect on one’s personal past and future. A total of 64 4- to 6-year-olds received tasks of delayed self-recognition, source memory, delay of gratification, and a newly developed task of future-oriented action timing. Although children’s performance on delayed self-recognition, source memory, and action timing improved with age, their performance on delay of gratification did not. Children’s errors in source memory and action timing were solely and strongly associated with each other in older children (5–6 years) even after controlling for age and verbal ability. Results are discussed in terms of mental time travel underlying episodic memory and future thinking that includes both the projection of oneself into the past and future and the appreciation of events’ temporal relations.     

A threat in the elder: the impact of task‐instructions,self‐efficacy and performance expectations on memory performance in the elderly

Widely used explicit memory tasks seem to overestimate age‐related differences in memory performance. Social and personal factors may buffer or undermine the effect of age on memory performance. In two studies, the performance of older adults was compared with the performance of younger adults. Tasks were presented either as memory tasks or non‐memory tasks. Older adults' performance on a memory task improved when the task‐instructions did not explicitly emphasize the memory component of the task. In the first study, results revealed that memory self‐efficacy beliefs play a moderator role on the impact of task‐instruction on memory performance, so that lower levels of memory self‐efficacy correlate with lower performance in the memory emphasizing task condition but not in the orientation emphasizing task condition. In a second study actual performance expectations were measured. For older participants only, expectations were sensitive to task‐instructions and mediated the relation between tasks‐instructions and performances. These findings suggest that observed age‐related differences in memory performance may be significantly exaggerated by the testing situation and by a low memory self‐efficacy and low memory performance expectancies prevalent among older adults. Copyright © 2005 John Wiley & Sons, Ltd.     

Selective attention in children with reading problems: A developmental study of incidental learning

The performance of poor readers and control children at three grade levels, first, third, and fifth grades, was compared on an incidental learning task adapted by Hagen (1967). A significant group by task interaction in a repeated measures ANOVA indicated that reading ability was differentially related to performance on the tasks. Relative to control children at all grade levels, poor readers obtained lower scores on the central task and higher scores on the incidental task. The absence of a grade × task × reading ability interaction indicated that selective attention follows the same developmental course in poor readers as in control children. The data suggest that the development of selective attention as reflected in performance on this task is delayed from 2 to 4 years in poor readers.We wish to thank the Sachem School District for permission to test the children, Mr. Morgan, reading specialist, and the teachers and children involved for their cooperation. We thank especially Mr. David Mello, principal of the Chippewa Elementary School for his invaluable assistance. We also thank Gordon Hale for providing the stimulus materials used in the study and for helpful suggestions regarding procedural details.     

Aging affects word-stem completion and recognition but not category generation

In this study, we investigated the effect of aging on two implicit memory tasks, word-stem completion and category generation, and on explicit recognition. We compared the performance of young and older adults on these implicit memory tasks with those of explicit recognition. We expected better performance of young than older adults in the explicit memory task and similar priming in both implicit memory tasks. The results showed that young adults performed better than older adults in the recognition task. Moreover, both age groups showed priming in the implicit memory tasks, although priming was greater in young adults compared to older adults in the word-stem completion memory task, whereas both age groups showed similar levels of priming in the category generation task. The present results showed dissociations as a function of age not only between the explicit and the implicit tasks but also between the implicit tasks.     

Children's initial sleep‐associated changes in motor skill are unrelated to long‐term skill levels

Sleep is considered to support the formation of skill memory. In juvenile but not adult song birds learning a tutor's song, a stronger initial deterioration of song performance over night‐sleep predicts better song performance in the long run. This and similar observations have stimulated the view of sleep supporting skill formation during development in an unsupervised off‐line learning process that, in the absence of external feedback, can initially also enhance inaccuracies in skill performance. Here we explored whether in children learning a motor sequence task, as in song‐learning juvenile birds, changes across sleep after initial practice predict performance levels achieved in the long run. The task was a serial reaction time task (SRTT) where subjects had to press buttons which were lighted up in a repeating eight‐element sequence as fast as possible. Twenty‐five children (8–12 years) practised the task in the evening before nocturnal sleep which was recorded polysomnographically. Retrieval was tested on the following morning and again 1 week later after daily training on the SRTT. As expected, changes in response speed over the initial night of sleep were negatively correlated with final performance speed after the 1‐week training. However, unlike in song birds, this correlation was driven by the baseline speed level achieved before sleep. Baseline‐corrected changes in speed or variability over the initial sleep period did not predict final performance on the trained SRTT sequence, or on different sequences introduced to assess generalization of the trained behaviour. The lack of correlation between initial sleep‐dependent changes and long‐term performance might reflect that the children were too experienced for the simple SRTT, possibly also favouring ceiling effects in performance. A consistent association found between sleep spindle activity and explicit sequence knowledge alternatively suggests that the expected correlation was masked by explicit memory systems interacting with skill memory formation.     

自我表征的可塑性:基于橡胶手错觉的研究

自我识别是人类自我觉知的行为标记。传统方法认为稳定的自我表征是自我识别的基础。随着对橡胶手错觉及一系列自我表征和自我识别错觉的揭示,这一能让人将外部客体感知为自身一部分的错觉研究使得我们能够以多感官整合的方式来研究自我表征和自我识别。拥有感和自主感被认为是我们进行自我识别的两类基本体验,本文对一系列橡胶手错觉范式研究的系统回顾表明,拥有感和自主感会发生改变,这说明人的自我表征是可变的和可塑的。     

Procedural learning: A developmental study of motor sequence learning and probabilistic classification learning in school-aged children

In this study, we investigated motor and cognitive procedural learning in typically developing children aged 8–12 years with a serial reaction time (SRT) task and a probabilistic classification learning (PCL) task. The aims were to replicate and extend the results of previous SRT studies, to investigate PCL in school-aged children, to explore the contribution of declarative knowledge to SRT and PCL performance, to explore the strategies used by children in the PCL task via a mathematical model, and to see whether performances obtained in motor and cognitive tasks correlated. The results showed similar learning effects in the three age groups in the SRT and in the first half of the PCL tasks. Participants did not develop explicit knowledge in the SRT task whereas declarative knowledge of the cue–outcome associations correlated with the performances in the second half of the PCL task, suggesting a participation of explicit knowledge after some time of exposure in PCL. An increasing proportion of the optimal strategy use with increasing age was observed in the PCL task. Finally, no correlation appeared between cognitive and motor performance. In conclusion, we extended the hypothesis of age invariance from motor to cognitive procedural learning, which had not been done previously. The ability to adopt more efficient learning strategies with age may rely on the maturation of the fronto-striatal loops. The lack of correlation between performance in the SRT task and the first part of the PCL task suggests dissociable developmental trajectories within the procedural memory system.     

Self-recognition and self-regulation: the relationship with socialization trajectories and children's sex

The initial process of self development involves interaction with others and the establishment of relationships taking different paths depending on the socio-cultural context. Self-recognition and self-regulation are considered manifestations of this development between 18 and 24 months of age. This study aimed at analyzing the relationship between these two aspects, maternal beliefs about autonomy and relatedness, as well as identifying differences between boys and girls in this developmental stage. Participants were 94 mothers of different educational levels and their children of 17-22 months of age in two Brazilian cities. Socialization Goals Inventory and Parental Practices in the First Year Inventory were used to collect data on mothers' beliefs. Children performed tasks related to self-recognition (the mirror test) and self-regulation (compliance to requests). The group of mothers studied valued both autonomy and interdependence. Children's responses are consistent with a perspective of relational autonomy, which value both independence and interdependence. Differences were found in relation to sex in both self-recognition and self-regulation, and baby girls showed superior performance than boys in both tasks.     

Preschool children's comprehension and production of directive forms

Thirty preschool children, 10 each at the 3-,4-, and 5-year-old levels, participated in two structured tasks designed to assess both comprehension and production of a full range of directive forms. In contrast to previous reports, the results indicated no significant differences in directive comprehension or production as a function of age; children in all age groups demonstrated the ability to understand and verbally encode the intent of most types of directive forms. However, the two most implicit forms, Question Directives and Hints, were complied with significantly less frequently than the more explicit forms, and were uused less often in the production task. The present findings indicate the importance of analyzing directive forms along a continuum of explicitness rather than dichotomizing them as direct versus indirect. Finally, the results are interpreted as providing indirect support for the general notion that mastery of some implicit forms may be achieved later than the acquisition of more explicit forms.     

Memory for things forgotten.

As previous research has shown, items not recalled on an initial memory task are not simply forgotten. Often, some can be recalled on a later, second task. Further, subjects can generally predict, in terms of feeling-of-knowing (FOK) ratings, which items will be subsequently recalled. Two experiments were carried out to assess both second-task performance and FOK accuracy for unrecalled items as a function of two factors, encoding manipulations (levels of processing in Experiment 1, study time in Experiment 2) and the nature of the second task (explicit or implicit cued stem completion). Results indicate that although levels of processing affected explicit second-task performance more than implicit second-task performance, it increased FOK accuracy in both types of tasks. Study time, however, affected FOK accuracy only in the explicit second task. Apparently, only when subjects were able to do some elaborative processing on the items did their FOK ratings reflect information relating to factors that drive performance on implicit tasks.     

Unconscious activation of task sets

Using an explicit task cuing paradigm, we tested whether masked cues can trigger task-set activation, which would suggest that unconsciously presented stimuli can impact cognitive control processes. Based on a critical assessment of previous findings on the priming of task-set activation, we present two experiments with a new method to approach this subject. Instead of using a prime, we varied the visibility of the cue. These cues either directly signaled particular tasks in Experiment 1, or certain task transitions (i.e., task repetitions or switches) in Experiment 2. While both masked task and transition cues affected task choice, only task cues affected the speed of task performance. This observation suggests that task-specific stimulus–response rules can be activated only by masked cues that are uniquely associated with a particular task. Taken together, these results demonstrate that unconsciously presented stimuli have the power to activate corresponding task sets.     

Choking and excelling under pressure

Decrements in performance on cognitive tasks resulting from pressure to perform (i.e., choking) are thought to be caused by interference with the ability to use explicit strategies (the distraction theory). This view suggests that pressure should improve performance on tasks for which explicit strategies hamper performance. This hypothesis was tested by giving subjects one of two nearly identical learning tasks, a task that required learning a rule or one that required using a holistic information-integration strategy. Explicit rule use would hurt performance in the latter task. As predicted by the distraction theory, pressure decreased performance on the rule-based task but enhanced performance on the information-integration task.