"I can't skip it": does free report improve accuracy in false memories?

Strategic monitoring of recognition memory by children and adults was examined using a semantic DRM procedure. Children (7- and 10-year-olds) and adults (overall N = 393) studied lists of semantically related words either incidentally or intentionally and were tested with old items, new items and critical lures to judge as old or new. Participants either made a decision about every item they saw (forced report), or they had the opportunity to withhold answers they were uncertain about (free report). Children were less likely to withhold an answer than adults. However, 7-year-olds were more able to resist false memories when given the opportunity to withhold an answer compared to 10-year-olds or adults. In contrast, adults were unable to improve false memory accuracy. These data suggest that once semantically induced false memories have been encoded they are amenable to strategic monitoring at retrieval in children but not adults.

Piecing Together the Puzzle of Pictorial Representation: How Jigsaw Puzzles Index Metacognitive Development.

Jigsaw puzzles are ubiquitous developmental toys in Western societies, used here to examine the development of metarepresentation. For jigsaw puzzles this entails understanding that individual pieces, when assembled, produce a picture. In Experiment 1, 3- to 5-year-olds (N = 117) completed jigsaw puzzles that were normal, had no picture, or comprised noninterlocking rectangular pieces. Pictorial puzzle completion was associated with mental and graphical metarepresentational task performance. Guide pictures of completed pictorial puzzles were not useful. In Experiment 2, 3- to 4-year-olds (N = 52) completed a simplified task, to choose the correct final piece. Guide-use associated with age and specifically graphical metarepresentation performance. We conclude that the pragmatically natural measure of jigsaw puzzle completion ability demonstrates general and pictorial metarepresentational development at 4 years.

Bilinguals' inhibitory control and attentional processes in a visual perceptual task.

The aim was to examine theories of bilingual inhibitory control superiority in the visual domain. In an ambiguous figure task, the ability to reverse (switch) interpretations (e.g., duck-rabbit) was examined in 3-5-year-olds bilinguals and monolinguals (N = 67). Bilingualism was no performance predictor in conceptual tasks (Droodle task, false belief task, ambiguous figures production task) that did not pose inhibitory demands. Bilinguals outperformed monolinguals in the ability to reverse, suggesting superior inhibitory capacity per se. Once reversal was experienced there was no difference in the time it took to reverse or reversal frequency between bilinguals and monolinguals. Bayesian analyses confirmed statistical result patterns. Findings support the established view of bilinguals' superior domain-general inhibitory control. This might be brought to bear by attending the environment differently.

Item repetition and response deadline affect familiarity and recollection differently across childhood.

The aim was to examine how item repetition at encoding and response deadline at retrieval affect familiarity and recollection in 5-, 7-, or 11-year-old children (N = 156). Familiarity and recollection were estimated using a process dissociation paradigm. Direct comparison of the effects of repetition under unlimited and limited response time revealed a dissociation of familiarity and recollection. The recollection was both boosted (via repetition) and reduced (via a response time limit). The familiarity was unaffected by a response time limit. Moreover, repetition boosted familiarity only under unlimited response time. Together with several distinct age-related increases for recollection and familiarity, these results provide a challenge to single-process accounts of recognition memory.

Children's perception of visual and auditory ambiguity and its link to executive functions and creativity.

The phenomenon of perceptual bistability provides insights into aspects of perceptual processing not normally accessible to everyday experience. However, most experiments have been conducted in adults, and it is not clear to what extent key aspects of perceptual switching change through development. The current research examined the ability of 6-, 8-, and 10-year-old children (N = 66) to switch between competing percepts of ambiguous visual and auditory stimuli and links between switching rate, executive functions, and creativity. The numbers of switches participants reported in two visual tasks (ambiguous figure and ambiguous structure from motion) and two auditory tasks (verbal transformation and auditory streaming) were measured in three 60-s blocks. In addition, inhibitory control was measured with a Stroop task, set shifting was measured with a verbal fluency task, and creativity was measured with a divergent thinking task. The numbers of perceptual switches increased in all four tasks from 6 to 10 years of age but differed across tasks in that they were higher in the verbal transformation and ambigous structure-from-motion tasks than in the ambigous figure and auditory streaming tasks for all age groups. Although perceptual switching rates differed across tasks, there were predictive relationships between switching rates in some tasks. However, little evidence for the influence of central processes on perceptual switching was found. Overall, the results support the notion that perceptual switching is largely modality and task specific and that this property is already evident when perceptual switching emerges.

Similar but separate systems underlie perceptual bistability in vision and audition.

The dynamics of perceptual bistability, the phenomenon in which perception switches between different interpretations of an unchanging stimulus, are characterised by very similar properties across a wide range of qualitatively different paradigms. This suggests that perceptual switching may be triggered by some common source. However, it is also possible that perceptual switching may arise from a distributed system, whose components vary according to the specifics of the perceptual experiences involved. Here we used a visual and an auditory task to determine whether individuals show cross-modal commonalities in perceptual switching. We found that individual perceptual switching rates were significantly correlated across modalities. We then asked whether perceptual switching arises from some central (modality-) task-independent process or from a more distributed task-specific system. We found that a log-normal distribution best explained the distribution of perceptual phases in both modalities, suggestive of a combined set of independent processes causing perceptual switching. Modality- and/or task-dependent differences in these distributions, and lack of correlation with the modality-independent central factors tested (ego-resiliency, creativity, and executive function), also point towards perceptual switching arising from a distributed system of similar but independent processes.

Are developments in mental scanning and mental rotation related?

The development and relation of mental scanning and mental rotation were examined in 4-, 6-, 8-, 10-year old children and adults (N = 102). Based on previous findings from adults and ageing populations, the key question was whether they develop as a set of related abilities and become increasingly differentiated or are unrelated abilities per se. Findings revealed that both mental scanning and rotation abilities develop between 4- and 6 years of age. Specifically, 4-year-olds showed no difference in accuracy of mental scanning and no scanning trials whereas all older children and adults made more errors in scanning trials. Additionally, the minority of 4-year-olds showed a linear increase in response time with increasing rotation angle difference of two stimuli in contrast to all older participants. Despite similar developmental trajectories, mental scanning and rotation performances were unrelated. Thus, adding to research findings from adults, mental scanning and rotation appear to develop as a set of unrelated abilities from the outset. Different underlying abilities such as visual working memory and spatial coding versus representing past and future events are discussed.

Ego depletion in visual perception: Ego-depleted viewers experience less ambiguous figure reversal.

This study examined the effects of ego depletion on ambiguous figure perception. Adults (N = 315) received an ego depletion task and were subsequently tested on their inhibitory control abilities that were indexed by the Stroop task (Experiment 1) and their ability to perceive both interpretations of ambiguous figures that was indexed by reversal (Experiment 2). Ego depletion had a very small effect on reducing inhibitory control (Cohen's d = .15) (Experiment 1). Ego-depleted participants had a tendency to take longer to respond in Stroop trials. In Experiment 2, ego depletion had small to medium effects on the experience of reversal. Ego-depleted viewers tended to take longer to reverse ambiguous figures (duration to first reversal) when naïve of the ambiguity and experienced less reversal both when naïve and informed of the ambiguity. Together, findings suggest that ego depletion has small effects on inhibitory control and small to medium effects on bottom-up and top-down perceptual processes. The depletion of cognitive resources can reduce our visual perceptual experience.

The format of children's mental images: Evidence from mental scanning.

This study examined the development and format of children's mental images. Children (4-, 5-, 6-7-, 8-9-, and 11-year-olds) and adults (N=282) viewed a map of a fictitious island containing various landmarks and two misleading signposts, indicating that some equidistant landmarks were different distances apart. Five-year-olds already revealed the linear time-distance scanning effect, previously shown in adults (Experiments 1 and 2): They took longer to mentally scan their image of the island with longer distances between corresponding landmarks, indicating the depictive format of children's mental images. Unlike adults, their scanning times were not affected by misleading top-down distance information on the signposts until age 8 (Experiment 1) unless they were prompted to the difference from the outset (Experiment 2). Findings provide novel insights into the format of children's mental images in a mental scanning paradigm and show that children's mental images can be susceptible to top-down influences as are adults'.

How Visuo-Spatial Mental Imagery Develops: Image Generation and Maintenance.

Two experiments examined the nature of visuo-spatial mental imagery generation and maintenance in 4-, 6-, 8-, 10-year old children and adults (N = 211). The key questions were how image generation and maintenance develop (Experiment 1) and how accurately children and adults coordinate mental and visually perceived images (Experiment 2). Experiment 1 indicated that basic image generation and maintenance abilities are present at 4 years of age but the precision with which images are generated and maintained improves particularly between 4 and 8 years. In addition to increased precision, Experiment 2 demonstrated that generated and maintained mental images become increasingly similar to visually perceived objects. Altogether, findings suggest that for simple tasks demanding image generation and maintenance, children attain adult-like precision younger than previously reported. This research also sheds new light on the ability to coordinate mental images with visual images in children and adults.

Process dissociation of familiarity and recollection in children: response deadline affects recollection but not familiarity.

According to dual-process theories, recollection (slow and associated with contextual details) and familiarity (fast and automatic) are two independent processes underlying recognition memory. An adapted version of the process dissociation paradigm was used to measure recognition memory in 5-, 7-, and 11-year-olds and adults. In Experiment 1, it was found that 5-year-olds already recollect details of items (i.e., number). Recollection increased particularly between 5 and 7 years. Familiarity differed between 5 years and adulthood. In Experiment 2, under limited response time during retrieval, recollection was eliminated in 5-year-olds and reduced across all ages, whereas familiarity was left unaffected. Together, these findings are consistent with dual-process theories of recognition memory and provide support for two processes underlying recognition memory from a developmental perspective.

Getting the picture: iconicity does not affect representation-referent confusion.

Three experiments examined 3- to 5-year-olds' (N = 428) understanding of the relationship between pictorial iconicity (photograph, colored drawing, schematic drawing) and the real world referent. Experiments 1 and 2 explored pictorial iconicity in picture-referent confusion after the picture-object relationship has been established. Pictorial iconicity had no effect on referential confusion when the referent changed after the picture had been taken/drawn (Experiment 1) and when the referent and the picture were different from the outset (Experiment 2). Experiment 3 investigated whether children are sensitive to iconicity to begin with. Children deemed photographs from a choice of varying iconicity representations as best representations for object reference. Together, findings suggest that iconicity plays a role in establishing a picture-object relation per se but is irrelevant once children have accepted that a picture represents an object. The latter finding may reflect domain general representational abilities.

Inhibitory processes in visual perception: a bilingual advantage.

Bilingual inhibitory control advantages are well established. An open question is whether inhibitory superiority also extends to visual perceptual phenomena that involve inhibitory processes. This research used ambiguous figures to assess inhibitory bilingual superiority in 3-, 4-, and 5-year-old mono- and bilingual children (N=141). Findings show that bilinguals across all ages are superior in inhibiting a prevalent interpretation of an ambiguous figure to perceive the alternative interpretation. In contrast, mono- and bilinguals revealed no differences in understanding that an ambiguous figure can have two distinct referents. Together, these results suggest that early bilingual inhibitory control superiority is also evident in visual perception. Bilinguals' conceptual understanding of figure ambiguity is comparable to that of their monolingual peers.

The development of automatic and controlled inhibitory retrieval processes in true and false recall.

In three experiments, we investigated the role of automatic and controlled inhibitory retrieval processes in true and false memory development in children and adults. Experiment 1 incorporated a directed forgetting task to examine controlled retrieval inhibition. Experiments 2 and 3 used a part-set cue and retrieval practice task to examine automatic retrieval inhibition. In the first experiment, the forget cue had no effect on false recall for adults but reduced false recall for children. In Experiments 2 and 3, both tasks caused retrieval impairments for true and false recall, and this occurred for all age groups. Implicit inhibition, which occurs outside of our conscious control, appears early in childhood. However, because young children do not process false memories as automatically as adults, explicit inhibition can reduce false memory output.

Children with autism's perception and understanding of ambiguous figures: evidence for pictorial metarepresentation, a research note.

A large body of autism research over the last 20 years has shown that people with autism have difficulties understanding mental states. This has been conceived of as a metarepresentational deficit. An open question is whether people with autism's metarepresentational deficit is limited to the mental domain. This research explores individuals with autism's understanding of the representational nature of pictures. With the use of ambiguous figures, where a single stimulus is capable of representing two distinct referents, we compared metarepresentational abilities in the pictorial and mental domains and the perception of pictorial ambiguity. Our findings indicate that individuals with autism are impaired in mental metarepresentation but not in pictorial metarepresentation. These findings suggest that children with autism understand the representational nature of pictures. We conclude that children with autism's understanding of the representational nature of pictures is in advance of their metarepresentational understanding of mind. Their perception of figure ambiguity is comparable to the typical population.

Valence and the development of immediate and long-term false memory illusions.

Across five experiments we examined the role of valence in children's and adults' true and false memories. Using the Deese/Roediger-McDermott paradigm and either neutral or negative-emotional lists, both adults' (Experiment 1) and children's (Experiment 2) true recall and recognition was better for neutral than negative items, and although false recall was also higher for neutral items, false recognition was higher for negative items. The last three experiments examined adults' (Experiment 3) and children's (Experiments 4 and 5) 1-week long-term recognition of neutral and negative-emotional information. The results replicated the immediate recall and recognition findings from the first two experiments. More important, these experiments showed that although true recognition decreased over the 1-week interval, false recognition of neutral items remained unchanged whereas false recognition of negative-emotional items increased. These findings are discussed in terms of theories of emotion and memory as well as their forensic implications.

Are children's memory illusions created differently from those of adults? Evidence from levels-of-processing and divided attention paradigms.

In two experiments, we investigated the robustness and automaticity of adults' and children's generation of false memories by using a levels-of-processing paradigm (Experiment 1) and a divided attention paradigm (Experiment 2). The first experiment revealed that when information was encoded at a shallow level, true recognition rates decreased for all ages. For false recognition, when information was encoded on a shallow level, we found a different pattern for young children compared with that for older children and adults. False recognition rates were related to the overall amount of correctly remembered information for 7-year-olds, whereas no such association was found for the other age groups. In the second experiment, divided attention decreased true recognition for all ages. In contrast, children's (7- and 11-year-olds) false recognition rates were again dependent on the overall amount of correctly remembered information, whereas adults' false recognition was left unaffected. Overall, children's false recognition rates changed when levels of processing or divided attention was manipulated in comparison with adults. Together, these results suggest that there may be both quantitative and qualitative changes in false memory rates with age.

The development of automatic associative processes and children's false memories.

We investigated children's ability to generate associations and how automaticity of associative activation unfolds developmentally. Children generated associative responses using a single associate paradigm (Experiment 1) or a Deese/Roediger-McDermott (DRM)-like multiple associates paradigm (Experiment 2). The results indicated that children's ability to generate meaningful word associates, and the automaticity with which they were generated, increased between 5, 7, and 11 years of age. These findings suggest that children's domain-specific knowledge base and the associative connections among related concepts are present and continue to develop from a very early age. Moreover, there is an increase in how these concepts are automatically activated with age, something that results from domain-general developments in speed of processing. These changes are consistent with the neurodevelopmental literature and together may provide a more complete explanation of the development of memory illusions.

The role of associative strength in children's false memory illusions.

The effects of associative strength on rates of 7- and 11-year-old children's true and false memories were examined when category and Deese-Roediger-McDermott (DRM) lists were used to cue the same critical lure. Backward associative strength (BAS) was varied such that the category and DRM lists had the same strength (DRM=category), DRM lists had more BAS (DRM>category), or category lists had more BAS (DRM