Cross-sectional and longitudinal assessment of cognitive development in Williams syndrome.

Williams syndrome (WS) is a rare genetic syndrome. As with all rare syndromes, obtaining adequately powered sample sizes is a challenge. Here we present legacy data from seven UK labs, enabling the characterisation of cross-sectional and longitudinal developmental trajectories of verbal and non-verbal development in the largest sample of individuals with WS to-date. In Study 1, we report cross-sectional data between N = 102 and N = 209 children and adults with WS on measures of verbal and non-verbal ability. In Study 2, we report longitudinal data from N = 17 to N = 54 children and adults with WS who had been tested on at least three timepoints on these measures. Data support the WS characteristic cognitive profile of stronger verbal than non-verbal ability, and shallow developmental progression for both domains. Both cross-sectional and longitudinal data demonstrate steeper rates of development in the child participants than the adolescent and adults in our sample. Cross-sectional data indicate steeper development in verbal than non-verbal ability, and that individual differences in the discrepancy between verbal and non-verbal ability are largely accounted for by level of intellectual functioning. A diverging developmental discrepancy between verbal and non-verbal ability, whilst marginal, is not mirrored statistically in the longitudinal data. Cross-sectional and longitudinal data are discussed with reference to validating cross-sectional developmental patterns using longitudinal data and the importance of individual differences in understanding developmental progression.

Age-related differences in the removal of information from working memory.

Removal has been assumed to be a core mechanism in working memory. However, it remains unclear whether children can actively remove outdated information from working memory and how this ability develops as children age. The current study aimed to examine age-related differences in removal ability and its relations with cognitive control and working memory capacity. Children aged 7, 9, and 11 years performed a modified working memory updating task assessing removal efficiency. In addition, a battery of cognitive control and working memory capacity tasks was administered. Results indicated that updating response times decreased considerably when a longer time was given for removal, suggesting that children aged 7 to 11 years can actively remove outdated items from working memory prior to encoding the new ones and that removal efficiency increased with age. More important, age-related increases in removal efficiency occurred concurrently with the development of working memory capacity. Proactive control predicted removal efficiency over and beyond age and working memory capacity. The findings shed new light on the mechanisms underlying the development of working memory updating.

No evidence for cross-paradigm transfer of abstract task knowledge in adults and school-aged children.

Cognitive control is a hallmark of human cognition. A large number of studies have focused on the plasticity of cognitive control and examined how repeated task experience leads to the improvement of cognitive control in novel task environments. However, it has been demonstrated that training-induced changes are very selective and that transfer occurs within one task paradigm but not across different task paradigms. The current study tested the possibility that cross-paradigm transfer would occur if a common cognitive control strategy is employed across different task paradigms. Specifically, we examined whether prior experience of using reactive control in one task paradigm (i.e., either the cued task-switching paradigm or the AX-CPT) makes adults (N = 137) and 9- to 10-year-olds (N = 126) respond in a reactive way in a subsequent condition of another task paradigm in which proactive control could have been engaged. Bayesian generalized mixed-effects models revealed clear evidence of an absence of cross-paradigm transfer of reactive control in both adults and school-aged children. Based on these findings, we discuss to what extent learned control could be transferred across different task contexts and the task-specificity of proactive/reactive control strategies.

Prior task experience increases 5-year-old children's use of proactive control: Behavioral and pupillometric evidence.

Children engage cognitive control reactively when they encounter conflicts; however, they can also resolve conflicts proactively. Recent studies have begun to clarify the mechanisms that support the use of proactive control in children; nonetheless, sufficient knowledge has not been accumulated regarding these mechanisms. Using behavioral and pupillometric measures, we tested the novel possibility that 5-year-old children (N = 58) learn to use proactive control via the acquisition of abstract task knowledge that captures regularities of the task. Participants were assigned to either a proactive training group or a control training group. In the proactive training group, participants engaged in a training phase where using proactive control was encouraged, followed by a test phase using different stimuli where both proactive and reactive control could be used. In the control training group, participants engaged in a training phase where both cognitive control strategies could be used, followed by a similarly-structured test phase using different stimuli. We demonstrated children in the control training group responded more quickly and accurately and showed greater cue-related pupil dilation in the test phase than in the training phase. However, there were no differences in response times, accuracies, and pupil dilation between the proactive and control training groups in the training and test phases. These findings suggest that prior task experience, that goes beyond specific knowledge about the timing of task goal activation, can lead children to engage more proactive control endogenously, even if they are not directly encouraged to do so.

Interpreting potential markers of storage and rehearsal: Implications for studies of verbal short-term memory and neuropsychological cases.

Neuropsychological studies of verbal short-term memory have often focused on two signature effects - phonological similarity and word length - the absence of which has been taken to indicate problems in phonological storage and rehearsal respectively. In the present study we present a possible alternative reading of such data, namely that the absence of these effects can follow as a consequence of an individual's poor level of recall. Data from a large normative sample of 251 adult participants were re-analyzed under the assumption that the size of phonological similarity and word length effects are proportional to an individual's overall level of recall. For both manipulations, when proportionalized effects were plotted against memory span, the same function fit the data in both auditory and visual presentation conditions. Furthermore, two additional sets of single-case data were broadly comparable to those that would be expected for an individual's level of verbal short-term memory performance albeit with some variation across tasks. These findings indicate that the absolute magnitude of phonological similarity and word length effects depends on overall levels of recall, and that these effects are necessarily eliminated at low levels of verbal short-term memory performance. This has implications for how one interprets any variation in the size of these effects, and raises serious questions about the causal direction of any relationship between impaired verbal short-term memory and the absence of phonological similarity or word length effects.

Demonstrating the effects of phonological similarity and frequency on item and order memory in Down syndrome using process dissociation.

It is important to distinguish between memory for item information and memory for order information when considering the nature of verbal short-term memory (vSTM) performance. Although other researchers have attempted to make this distinction between item and order memory in children, none has done so using process dissociation. This study shows that such an approach can be particularly useful and informative. Individuals with Down syndrome (DS) tend to experience a vSTM deficit. These two experiments explored whether phonological similarity (Experiment 1) and item frequency (Experiment 2) affected vSTM for item and order information in a group of individuals with DS compared with typically developing (TD) vocabulary-matched children. Process dissociation was used to obtain measures of item and order memory via Nairne and Kelley's procedure (Journal of Memory and Language, 50 (2004) 113-133). Those with DS were poorer than the matched TD group for recall of both item and order information. However, in both populations, phonologically similar items reduced order memory but enhanced item memory, whereas high-frequency items resulted in improvements in both item and order memory-effects that are in line with previous research in the adult literature. These results indicate that, despite poorer vSTM performance in DS, individuals experience phonological coding of verbal input and a contribution of long-term memory knowledge to recall. These findings inform routes for interventions for those with DS, highlighting the need to enhance both item and order memory. Moreover, this work demonstrates that process dissociation is applicable and informative for studying special populations and children.

When stimulus variability accelerates the learning of task knowledge in adults and school-aged children.

Experience with instances that vary in their surface features helps individuals to form abstract task knowledge, leading to transfer of that knowledge to novel contexts. The current study sought to examine the role of this variability effect in how adults and school-aged children learn to engage cognitive control. We focused on the engagement of cognitive control in advance (proactive control) and in response to conflicts (reactive control) in a cued task-switching paradigm, and conducted four preregistered online experiments with adults (Experiment 1A: N = 100, Experiment 1B: N = 105) and 9- to 10-year-olds (Experiment 2A: N = 98, Experiment 2B: N = 97). It was shown that prior task experience of engaging reactive control makes both adults and 9- to 10-year-olds respond more slowly in a subsequent similar-structured condition with different stimuli in which proactive control could have been engaged. 9- to 10-year-olds (Experiment 2B) exhibited more negative transfer of a reactive control mode when uninformative cue and pre-target stimuli, which do not convey task-relevant information, were changed in each block, compared with when they were fixed. Furthermore, adults showed suggestive evidence of the variability effect both when cue and target stimuli were varied (Experiment 1A) and when uninformative cue and pre-target stimuli were varied (Experiment 1B). The collective findings of these experiments provide important insights into the contribution of stimulus variability to the engagement of cognitive control.

Evidence for positive and negative transfer of abstract task knowledge in adults and school-aged children.

Engaging cognitive control is essential to flexibly adapt to constantly changing environments. However, relatively little is known about how prior task experience impacts on the engagement of cognitive control in novel task environments. We aimed to clarify how individuals learn and transfer the engagement of cognitive control with a focus on the hierarchical and temporal aspects of task knowledge. Highlighting two distinct cognitive control processes, the engagement of cognitive control in advance (proactive control) and in response to conflicts (reactive control), we conducted six preregistered online experiments with both adults (Experiment 1, 3, and 5: N = 71, N = 108, and N = 70) and 9- to 10-year-olds (Experiment 2, 4, 6: N = 69, N = 108, and N = 70). Using two different experimental paradigms, we demonstrated that prior task experience of engaging reactive control makes adults and 9-to 10-year-olds respond in a reactive way in a subsequent similar-structured condition with different stimuli in which proactive control could have been engaged. This indicates that individuals do learn knowledge about the temporal structure of task goal activation and, on occasion, negatively transfer this knowledge. Furthermore, individuals exhibited these negative transfer effects in a similar-structured condition with different task goals and stimuli, indicating that they learn hierarchically-structured task knowledge. The collective findings suggest a new way of understanding how hierarchical and temporal task knowledge influences the engagement of cognitive control and highlight potential mechanisms underlying the near transfer effects observed in cognitive control training.

Poor phonemic discrimination does not underlie poor verbal short-term memory in Down syndrome.

Individuals with Down syndrome tend to have a marked impairment of verbal short-term memory. The chief aim of this study was to investigate whether phonemic discrimination contributes to this deficit. The secondary aim was to investigate whether phonological representations are degraded in verbal short-term memory in people with Down syndrome relative to control participants. To answer these questions, two tasks were used: a discrimination task, in which memory load was as low as possible, and a short-term recognition task that used the same stimulus items. Individuals with Down syndrome were found to perform significantly better than a nonverbal-matched typically developing group on the discrimination task, but they performed significantly more poorly than that group on the recognition task. The Down syndrome group was outperformed by an additional vocabulary-matched control group on the discrimination task but was outperformed to a markedly greater extent on the recognition task. Taken together, the results strongly indicate that phonemic discrimination ability is not central to the verbal short-term memory deficit associated with Down syndrome.

Expressive drawing ability in children with autism.

The autistic impairments in emotional and social competence, imagination and generating ideas predict qualitative differences in expressive drawings by children with autism beyond that accounted by any general learning difficulties. In a sample of 60 5-19-year-olds, happy and sad drawings were requested from 15 participants with non-savant autism and compared with those drawn by three control groups matched on either degree of learning difficulty (MLD), mental age (MA) or chronological age (CA). All drawings were rated by two artists on a 7-point quality of expression scale. Contrary to our predictions, the drawings from the autistic group were rated similar to those of the MA and MLD groups. Analysis of the people and social content of the drawings revealed that although children with autism did not draw fewer people, they did draw more immature forms than mental age controls. Furthermore, there was tentative evidence that fewer social scenes were produced by the autism sample. We conclude that the overall merit of expressive drawing in autism is commensurate with their general learning difficulties, but the social/emotional impairment in autism affects their drawings of people and social scenes.

Investigating the impact of the COVID-19 pandemic on older adolescents' psychological wellbeing and self-identified cognitive difficulties.

Background: The COVID-19 pandemic coincides with growing concern regarding the mental health of young people. Older adolescents have faced a particular set of pandemic-related challenges and demonstrate heightened vulnerability to affective disorders (particularly anxiety). Anxiety symptoms are associated with a range of cognitive difficulties. Older adolescents may therefore be susceptible to pandemic-related declines in wellbeing and associated cognitive difficulties. Methods: At three timepoints, independent samples of young people aged 16-18 years (N = 607, 242, 618 respectively) completed an online survey. Data collection coincided with periods of lockdown (timepoints 1 and 3) and young people returning to school (timepoint 2). The survey assessed subjective impacts of the pandemic on overall wellbeing, anxiety and cognitive function. Results: Findings demonstrated the detrimental impact of the COVID-19 pandemic on older adolescents' psychological wellbeing-a finding that was consistent across samples. The majority of young people at each timepoint experienced heightened anxiety. Crucially, pandemic-related anxiety was associated with self-identified cognitive difficulties, a pattern of association that was evident at all three timepoints. The nature and extent of these difficulties were predictive of specific pandemic-related concerns in this age group. Conclusions: Older adolescents' experiences of the pandemic are characterised by subjective declines in wellbeing and stable patterns of association between anxiety and self-identified cognitive difficulties. Implications are discussed with reference to future research and intervention.

To What Extent is the Contribution of Language to Learning via Instructions Modulated by the Expression of Autism Traits?

Language plays a fundamental role in enabling flexible, goal-directed behaviour. This study investigated whether the contribution of language to instruction encoding is modulated by the expression of autism traits, as measured by the Autism Spectrum Quotient (ASQ) questionnaire. Participants (N = 108) completed six choice reaction time tasks, with each task consisting of six stimulus-response mappings. During an instruction phase preceding each task, participants performed either a verbal, non-verbal or no distractor task. Participants made more errors in the verbal distractor task condition, but this detrimental effect did not differ significantly between the high (top 33%) and low (bottom 33%) ASQ groups. Hence, the contribution of language to instruction encoding does not appear to be modulated by the expression of autism traits.

Attention-deficit hyperactivity disorder traits are a more important predictor of internalising problems than autistic traits.

Autism Spectrum Disorder (ASD) and Attention-Deficit Hyperactivity Disorder (ADHD) are both linked to internalising problems like anxiety and depression. ASD and ADHD also often co-occur, making their individual statistical contributions to internalising disorders difficult to investigate. To address this issue, we explored the unique associations of self-reported ASD traits and ADHD traits with internalising problems using a large general population sample of adults from the United Kingdom (N = 504, 49% male). Classical regression analyses indicated that both ASD traits and ADHD traits were uniquely associated with internalising problems. Dominance and Bayesian analyses confirmed that ADHD traits were a stronger, more important predictor of internalising problems. However, brief depression and anxiety measures may not provide a comprehensive index of internalising problems. Additionally, we focused on recruiting a sample that was representative of the UK population according to age and sex, but not ethnicity, a variable that may be linked to internalising disorders. Nevertheless, our findings indicate that while ASD and ADHD uniquely predict internalising problems, ADHD traits are a more important statistical predictor than ASD traits. We discuss potential mechanisms underlying this pattern of results and the implications for research and clinical practice concerning neurodevelopmental conditions.

Assessing the effectiveness of online emotion recognition training in healthy volunteers.

Facial emotion recognition (ER) difficulties are associated with mental health and neurodevelopmental conditions, including autism and poorer social functioning. ER interventions may therefore have clinical potential. We investigated the efficacy of ER training (ERT). We conducted three online studies with healthy volunteers completing one ERT session. Studies 1 and 2 included active and control/sham training groups and tested the efficacy of (i) four-emotion ERT (angry, happy, sad and scared) (n = 101), and (ii) six-emotion ERT (adding disgusted and surprised) (n = 109). Study 3 tested generalizability of ERT to non-trained stimuli with groups trained and tested on the same stimuli, or different stimuli (n = 120). Training effects on total correct hits were estimated using linear mixed effects models. We did not observe clear evidence of improvement in study 1 but note the effect was in the direction of improvement (b = 0.02, 95% confidence interval (CI) = -0.02 to 0.07). Study 2 indicated greater total hits following training (b = 0.07, 95% CI = 0.03-0.12). Study 3 demonstrated similar improvement across groups (b = -0.01, 95% CI = -0.05 to 0.02). Our results indicate improved ER (as measured by our task), which generalizes to different facial stimulus sets. Future studies should further explore generalizability, longer-term effects and ERT in populations with known ER difficulties.

Inner speech is used to mediate short-term memory, but not planning, among intellectually high-functioning adults with autism spectrum disorder.

Evidence regarding the use of inner speech by individuals with autism spectrum disorder (ASD) is equivocal. To clarify this issue, the current study employed multiple techniques and tasks used across several previous studies. In Experiment 1, participants with and without ASD showed highly similar patterns and levels of serial recall for visually presented stimuli. Both groups were significantly affected by the phonological similarity of items to be recalled, indicating that visual material was spontaneously recoded into a verbal form. Confirming that short-term memory is typically verbally mediated among the majority of people with ASD, recall performance among both groups declined substantially when inner speech use was prevented by the imposition of articulatory suppression during the presentation of stimuli. In Experiment 2, planning performance on a tower of London task was substantially detrimentally affected by articulatory suppression among comparison participants, but not among participants with ASD. This suggests that planning is not verbally mediated in ASD. It is important that the extent to which articulatory suppression affected planning among participants with ASD was uniquely associated with the degree of their observed and self-reported communication impairments. This confirms a link between interpersonal communication with others and intrapersonal communication with self as a means of higher order problem solving.

Children's eyewitness memory: repeating post-event misinformation reduces the distinctiveness of a witnessed event.

Children may incorporate misinformation into reports of witnessed events, particularly if the misinformation is repeated. One explanation is that the misinformation trace is strengthened by repetition. Alternatively, repeating misinformation may reduce the discriminability between event and misinformation sources, increasing interference between them. We tested trace strength and distinctiveness accounts by showing 5- and 6-year-olds an event and then presenting either the "same" or "varying" items of post-event misinformation across three iterations. Performance was compared to a baseline in which misinformation was presented once. Repeating the same misinformation increased suggestibility when misinformation was erroneously attributed to both event and misinformation sources, supporting a trace strength interpretation. However, suggestibility measured by attributing misinformation solely to the event, was lower when misinformation was presented repeatedly rather than once. In contrast, identification of the correct source of the event was less likely if the misinformation was repeated, whether the same or different across iterations. Thus a reduction in the distinctiveness of sources disrupted memory for the event source. Moreover, there was strong association between memory for the event and a measure of distinctiveness of sources, which takes into account both the number of confusable source and their apparent temporal spacing from the point of retrieval.

Children's memory distortions following social contact with a co-witness: disentangling social and cognitive mechanisms.

This study examined whether recalling an event with a co-witness influences children's recall. Individual 3-5-year-olds (n = 48) watched a film with a co-witness. Unbeknown to participants, the co-witness was watching an alternative version of the film. Afterwards both the co-witness and the participant answered questions about the film together (public recall), and the degree to which children conformed to the co-witness's alternative version of events was measured. Subsequently participants were questioned again individually (private recall). Children also completed false belief and inhibitory control tasks. By separating errors made in public and private, the results indicated that both social conformity (32% of errors) and memory distortion (68% of errors) played a role in co-witness influence. Inhibitory control predicted the likelihood of retracting errors in private, but only for children who failed (r = .66) rather than passed false belief tasks (r = -.10). The results suggest that children with a theory of mind conform in the company of the co-witness to avoid social embarrassment, while those a poor theory of mind conform on the basis of an inability to inhibit the co-witness's response. The findings contribute to our understanding of the motivations responsible for co-witness conformity across early childhood.

How does language support the acquisition of novel cognitive tasks? Investigating the role of task complexity and task instructions.

Recent findings have shown that language plays an important role in the acquisition of novel cognitive tasks (van 't Wout & Jarrold, 2020). The current study sought to elucidate the factors that influence the contribution of language to novel task learning, focusing specifically on the role of task complexity (defined by the number of stimulus-response [S-R] rules per task) and the role of task instructions (by comparing trial-and-error learning to instruction-based learning). In each experiment participants were required to learn the correct response to novel sets of picture stimuli. When analyzed as a function of stimulus occurrence within a task, both experiments found that initial performance was worse under articulatory suppression (AS; verbal distractor task) than under foot tapping (i.e., nonverbal distractor task), but only if the task was more complex (consisting of 6S-R rules) and not if it was less complex (consisting of three or four S-R rules), suggesting that the acquisition of a simpler task by trial and error might not require verbal mediation. Experiment 2 furthermore found that the role of language was modulated by the manner of acquisition: For trial-and-error learning, the detrimental effect of AS increased and then decreased again as a function of stimulus occurrence. Conversely, for instruction-based learning, AS exclusively affected the first few stimulus occurrences, suggesting that participants can create a verbal representation of the task during the instruction phase. Together, these experiments demonstrate that the role of language in novel task learning is modulated by task complexity and task instructions. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Articulatory suppression during instruction encoding impedes performance in choice reaction time tasks.

Theories of instruction following assume that language contributes to our ability to understand and implement instructions. The two experiments reported here investigated that assumption. Participants (total N = 96) were required to learn a series of novel tasks, with each task consisting of six arbitrary stimulus-response rules. All tasks were preceded by an instruction phase (a visual depiction of the correct stimulus-response rules for each task), during which participants performed a verbal distractor task (articulatory suppression), a non-verbal distractor task (foot tapping) or no distractor task. Additionally, the duration of the instruction phase was varied so that it was either long (60 s) or short (30 s in Experiment 1, or 10 s in Experiment 2). In both experiments participants made more errors when they had performed articulatory suppression during the instruction interval, compared to the foot tapping and no distractor task conditions. Furthermore, Experiment 2 found that this detrimental effect of articulatory suppression was especially pronounced with a very short instruction duration. These findings demonstrate that language plays a crucial role in the encoding of novel task instructions, especially when instructions are encoded under time pressure.

Evidence Against Novelty-Gated Encoding in Serial Recall.

Novelty-gated encoding is the assumption that events are encoded more strongly into memory when they are more novel in comparison to previously encoded events. It is a core assumption of the SOB model of serial recall (Farrell & Lewandowsky, 2002). We present three experiments testing some predictions from novelty-gated encoding. Experiment 1 shows that the probability of recalling the third item in a list correctly does not depend on whether it is preceded by phonologically similar or dissimilar items. Experiment 2 shows that in lists of items from three classes (nonwords, spatial locations, and abstract drawings) the probability of recalling an item does not depend on whether it is preceded by items from the same or another class. Experiment 3 used a complex-span paradigm varying the phonological similarity of words that are read aloud as distractors in between memory items. Contrary to a prediction from novelty-gated encoding, similar distractors did not impair memory more than dissimilar distractors. The results question the assumption of novelty-gated encoding in serial recall. We discuss alternative explanations for the phenomena that this assumption has previously helped to explain. The present evidence against novelty-gated encoding might point to boundary conditions for the role of prediction error in the acquisition of memories.