The effect of labeling on preschool children's performance in the Dimensional Change Card Sort Task

Previous research suggests that experimenter-induced labeling of test cards improves preschoolers’ performance on the Dimensional Change Card Sort Task (DCCS), a measure of flexible rule use. Three experiments attempted to further clarify how labeling aids performance on the DCCS. Experiment 1 examined the nature of the labeling effect but failed to show any benefit of labeling on children's performance. Experiment 2 failed to replicate the labeling effect reported by [Kirkham, N. Z., Cruess, L. M., & Diamond, A. (2003). Helping children apply their knowledge to their behavior on a dimension-switching task. Developmental Science, 6, 449–467] despite closely matching their procedures. Experiment 3 demonstrated that labeling procedures designed to counteract the suppression of the post-switch sorting dimension also failed to improve performance on the DCCS. We discuss the implications of these findings for identifying factors that positively affect preschoolers’ cognitive flexibility.     

Deconstructing executive deficits among persons with autism: implications for cognitive neuroscience

Individuals with autism demonstrate impairments on measures of executive function (EF) relative to typically developing comparison participants. EF is comprised of several processes including inhibition, working memory and set shifting that develop throughout the lifespan. Impairments in EF may appear early in development and persist, or may represent a more transient delay which resolves with time. Given the unevenness of the cognitive profile of persons with autism, understanding the development of EF poses methodological challenges. These issues include those related to matching measures and the choice of comparison participants to which the performance of persons with autism will be compared. In the current review, we attempt to break down the processes of inhibition, working memory and set shifting among persons with autism. We propose to do this within a developmental perspective that highlights how matching measures and comparison participants can affect the interpretation of research findings.     

Components of executive control with advantages for bilingual children in two cultures

The present study used a behavioral version of an anti-saccade task, called the ‘faces task’, developed by [Bialystok, E., Craik, F. I. M., & Ryan, J. (2006). Executive control in a modified anti-saccade task: Effects of aging and bilingualism. Journal of Experimental Psychology: Learning, Memory, and Cognition, 32, 1341-1354] to isolate the components of executive functioning responsible for previously reported differences between monolingual and bilingual children and to determine the generality of these differences by comparing bilinguals in two cultures. Three components of executive control were investigated: response suppression, inhibitory control, and cognitive flexibility. Ninety children, 8-years old, belonged to one of three groups: monolinguals in Canada, bilinguals in Canada, and bilinguals in India. The bilingual children in both settings were faster than monolinguals in conditions based on inhibitory control and cognitive flexibility but there was no significant difference between groups in response suppression or on a control condition that did not involve executive control. The children in the two bilingual groups performed equivalently to each other and differently from the monolinguals on all measures in which there were group differences, consistent with the interpretation that bilingualism is responsible for the enhanced executive control. These results contribute to understanding the mechanism responsible for the reported bilingual advantages by identifying the processes that are modified by bilingualism and establishing the generality of these findings across bilingual experiences. They also contribute to theoretical conceptions of the components of executive control and their development.     

Bottom-up and top-down dynamics in young children's executive function: Labels aid 3-year-olds’ performance on the Dimensional Change Card Sort

Executive function (EF) improves between the ages of 3 and 5 and has been assessed reliably using the Dimensional Change Card Sort (DCCS), a task in which children first sort bivalent cards by one dimension (e.g., shape) and then are instructed to sort by a different dimension (e.g., color). Three-year-olds typically perseverate on the pre-switch dimension, whereas 5-year-olds switch flexibly. Labeling task stimuli can facilitate EF performance (0110 and 0060), but the nature of this effect is unclear. In 3 experiments we examined 2 hypotheses deriving from different theoretical perspectives: first, that labels facilitate performance in a more bottom-up fashion, by biasing attention to relevant task rules (Kirkham et al., 2003); and second, that labels aid performance in a more top-down fashion by prompting reflection and an understanding of the hierarchical nature of the task (Zelazo, 2004). Children performed better on the DCCS when labels referred to the relevant sorting dimension (Experiment 1). This was a function of the content of the labels rather than the change in auditory signal across phases (Experiment 2). Furthermore, labeling the opposite dimension only did not have a symmetrically negative effect on performance (Experiment 3). Together, these results suggest external, verbal labels bias children to attend to task-relevant information, likely through interaction with emerging top-down, endogenous control.     

The relations between children's communicative perspective-taking and executive functioning

Two experiments investigated children’s communicative perspective-taking ability. In Experiment 1, 4- to 5-year-old children were tested on two referential communication tasks, as well as on measures of inhibitory control, working memory, and cognitive flexibility. Results document children’s emergent use of the perspective of their speaking partner to guide their communicative behaviors in both a production and comprehension task. In Experiment 2, 3- to 4-year-old children used a speaker’s perspective to guide their interpretation of instructions. In both experiments, egocentric interpretations of speaker requests were negatively correlated with children’s inhibitory control skills. Results of these studies demonstrate that young children can differentiate between information that is accessible to the speaker versus privileged knowledge, and use this information to guide their communicative behaviors. Furthermore, the results suggest that children’s inhibitory control skills allow them to inhibit their own perspective, enabling them to make use of their communicative partner’s perspective.     

Representational and executive selection resources in 'theory of mind': evidence from compromised belief-desire reasoning in old age

Effective belief-desire reasoning requires both specialized representational capacities-the capacity to represent the mental states as such-as well as executive selection processes for accurate performance on tasks requiring the prediction and explanation of the actions of social agents. Compromised belief-desire reasoning in a given population may reflect failures in either or both of these systems. We report evidence supporting this two-process model from belief-desire reasoning tasks conducted with younger and older adult populations. When task inferential complexity is held constant, neither group showed specific difficulty with reasoning about mental state content as compared with non-mental state content. However, manipulations that systematically increase executive performance demands within belief-desire reasoning caused systematic decreases in task performance in both older and younger adult groups. Moreover, the effect of increasing executive demands was disproportionately greater in the older group. Regression analysis indicated that measures of processing speed and inhibition contributed most to explaining variance in accuracy and response times in the belief-desire reasoning tasks. These results are consistent with the idea that compromised belief-desire reasoning in old age is likely the result of age-related decline in executive selection skills that supplement core mental state representational abilities, rather than as a result of failures in the representational system itself.     

Development of hot and cool executive function during the transition to adolescence

This study examined the development of executive function (EF) in a typically developing sample from middle childhood to adolescence using a range of tasks varying in affective significance. A total of 102 participants between 8 and 15 years of age completed the Iowa Gambling Task, the Color Word Stroop, a Delay Discounting task, and a Digit Span task. Age-related improvements were found on all tasks, but improvements on relatively cool tasks (Color Word Stroop and Backward Digit Span) occurred earlier in this age range, whereas improvements on relatively hot tasks (Iowa Gambling Task and Delay Discounting) were more gradual and occurred later. Exploratory factor analysis indicated that performance on all tasks could be accounted for by a single-factor model. Together, these findings indicate that although similar abilities may underlie both hot and cool EF, hot EF develops relatively slowly, which may have implications for the risky behavior often observed during adolescence. Future work should include additional measures to characterize more intensively the development of both hot and cool EF during the transition to adolescence.     

Neurophysiological marker of inhibition distinguishes language groups on a non-linguistic executive function test

Successful interaction with the environment depends on flexible behaviors which require shifting attention, inhibiting primed responses, ignoring distracting information, and withholding motor responses. These abilities, termed executive function (EF), are believed to be mediated by inhibitory processes in the frontal lobes. Superior performance on EF tests (i.e., faster reaction times (RT), and fewer errors) has been shown in bilinguals compared to monolingual speakers. However, findings are inconsistent, and no study has directly linked this bilingual advantage to frontal lobe inhibitory processes. To clarify this uncertainty, we concomitantly tested neural inhibitory processes and behavioral responses on an EF test in bilinguals and monolinguals. Specifically, we compared English monolinguals (N = 15) to Spanish/English bilinguals (N = 13) on event-related brain potentials (ERP) during a non-linguistic, auditory Go/NoGo task, a task linked to non-motor, cognitive inhibition in monolinguals. Participants responded with a button press on trials in which target tone-pairs (Go trials) were presented and withheld their responses on non-target trials (NoGo trials). Results revealed significantly greater inhibition (i.e., greater mean N2 amplitude) in bilinguals compared to monolinguals during NoGo trials even though both groups performed the task equally well (i.e., withheld a motor response). On Go trials where participants pressed a response button, neither ERPs nor RT distinguished the groups. Additionally, scores on a second language proficiency test (i.e., English in our bilingual group) were positively correlated with N2 amplitude. These findings are the first to directly link this bilingual advantage to a neural correlate of inhibition and to reveal that inhibition in bilinguals is moderated by second language proficiency. Results are discussed in the context of plasticity, and we propose that evaluating bilinguals at varying levels of second-language proficiency may serve as a model of human neuroplasticity.     

The effect of repetitive saccade execution on the attention network test: Enhancing executive function with a flick of the eyes

The simple act of repeatedly looking left and right can enhance subsequent cognition, including divergent thinking, detection of matching letters from visual arrays, and memory retrieval. One hypothesis is that saccade execution enhances subsequent cognition by altering attentional control. To test this hypothesis, we compared performance following repetitive bilateral saccades or central fixation on the revised attention network test, which measures the operation of three distinct attentional networks: alerting, orienting, and executive function. The primary finding was that saccade execution increased the subsequent operation of the executive function network, which encompasses attentional control. Specifically, saccade execution decreased response time to target stimuli in the presence of response-incongruent flankers. A secondary finding was that saccade execution decreased response time to targets when an invalid location was cued prior to target onset. These findings suggest that saccades are an effective means of improving attentional control. Of greater theoretical importance, the study establishes attentional enhancement as a potential mechanism by which saccades enhance other aspects of cognition. Although some saccade execution effects have been found to depend on consistency of handedness (i.e., the consistency with which an individual uses one hand over the other), saccade-induced enhancement of attentional control occurred independently of handedness consistency.     

Choosing between two objects reduces 3-year-olds' errors on a reverse-contingency test of executive function

In the present experiment, we used a reversed-contingency paradigm (the windows task: [Russell, J., Mauthner, N., Sharpe, S., & Tidswell, T. (1991). The windows task as a measure of strategic deception in preschoolers and autistic subjects. British Journal of Developmental Psychology, 9, 331-349]) to explore the effect of alterations in the task array on 3-year-old children's strategic reasoning. Children were offered a choice between either a desirable object and an undesirable object, or between a desirable object and an empty location. There was significantly better performance on the two-object version of the task. This difference was evident even on subsequent trials when the second object was removed and the empty location reintroduced. This suggests that presenting children with a choice between two objects helps them to formulate a strategy, rather than to execute a previously determined response.     

The relationship between bilingualism and selective attention in young adults: Evidence from an ambiguous figures task

Previous research has shown that bilinguals outperform monolinguals on a variety of tasks that have been described as involving executive functioning, but the precise mechanism for those effects or a clear definition for “executive function” is unknown. This uncertainty has led to a number of studies for which no performance difference between monolingual and bilingual adults has been detected. One approach to clarifying these issues comes from research with children showing that bilinguals were more able than their monolingual peers to perceive both interpretations of an ambiguous figure, an ability that is more tied to a conception of selective attention than to specific components of executive function. The present study extends this notion to adults by assessing their ability to see the alternative image in an ambiguous figure. Bilinguals performed this task more efficiently than monolinguals by requiring fewer cues to identify the second image. This finding has implications for the role of selective attention in performance differences between monolinguals and bilinguals.     

The executive demands of strategic reasoning are modified by the way in which children are prompted to think about the task: Evidence from 3- to 4-year-olds

We investigated a test of strategic reasoning (the Windows task) that in different studies has yielded contrasting pictures of young children's executive abilities [Russell, J., Mauthner, N., Sharpe, S., & Tidswell, T. (1991). The “windows task” as a measure of strategic deception in preschoolers and autistic subjects. British Journal of Developmental Psychology, 9, 331–349; Samuels, M. C., Brooks, P. J., & Frye, D. (1996). Strategic game playing through the windows task. British Journal of Developmental Psychology, 14, 159–172]. An experiment with 52 three- to four-year-olds showed robust effects of different wordings for the prompts used to ask children to respond, and found that a single exposure to the facilitating wording led to improved performance on subsequent trials where the standard wording was used. This suggests that the effect of the wording was to help children infer an appropriate basis for responding, and not to reduce the trial-by-trial working memory or inhibitory demands of the task.     

The impact of Parkinson's disease on sequence learning: perceptual pattern learning and executive function

The current study examined the contribution of brain areas affected by Parkinson's disease (PD) to sequence learning, with a specific focus on response-related processes, spatial attentional control, and executive functioning. Patients with mild PD, patients with moderate PD, and healthy age-matched participants performed three tasks-a sequence learning task with a spatial pattern that was incidental to response selection, a spatial cuing task, and neuropsychological tests of executive function. Whereas moderate PD patients failed to show significant sequence learning, mild PD patients performed comparably with controls. Neither group of PD patients was impaired in the control of spatial attention. Sequence learning was correlated with neuropsychological measures of executive function but not with the ability to control spatial attention. These results suggest that the contribution of the brain areas affected by PD to sequence learning extends beyond motor learning to include the learning of perceptual patterns and involves executive function, including cognitive flexibility and set shifting.     

Complexity effects on the children's gambling task

The children's gambling task (CGT [Kerr, A., & Zelazo, P. D. (2004). Development of “Hot” executive function: The children's gambling task. Brain and Cognition, 55, 148–157]) involves integrating information about losses and gains to maximize winnings when selecting cards from two decks. Both cognitive complexity and control (CCC) theory and relational complexity (RC) theory attribute younger children's difficulty to task complexity. In CCC theory, identification of the advantageous deck requires formulation of a higher-order rule so that gains and losses can be considered in contradistinction. According to RC theory, it entails processing the ternary relation linking three variables (deck, magnitude of gain, magnitude of loss). We designed two less complex binary-relational versions in which either loss or gain varied across decks, with the other held constant. The three closely matched versions were administered to 3–5-year-olds. Consistent with complexity explanations, children in all age groups selected cards from the advantageous deck in the binary-relational versions, but only 5-year-olds did so on the ternary-relational CGT.     

Parent rating of executive function in fetal alcohol spectrum disorder: A review of the literature and new data on Aboriginal Canadian children

Aboriginal children in Canada are at high risk of fetal alcohol spectrum disorder (FASD) but there is little research on the cognitive impact of prenatal alcohol exposure (PAE) in this population. This paper reviews the literature on parent report of executive functioning in children with FASD that used the Behavior Rating Inventory of Executive Function (BRIEF). New data on the BRIEF is then reported in a sample of 52 Aboriginal Canadian children with FASD for whom a primary caregiver completed the BRIEF. The children also completed a battery of neuropsychological tests. The results reveal mean scores in the impaired range for all three BRIEF index scores and seven of the eight scales, with the greatest difficulties found on the Working Memory, Inhibit and Shift scales. The majority of the children were reported as impaired on the index scores and scales, with Working Memory being most commonly impaired scale. On the performance-based tests, Trails B and Letter Fluency are most often reported as impaired, though the prevalence of impairment is greater for parent ratings than test performance. No gender difference is noted for the parent report, but the boys had slightly slower intellectual functioning and were more perseverative than the girls on testing. The presence of psychiatric comorbidity is unrelated to either BRIEF or test scores. These findings are generally consistent with prior studies indicating that parents observe considerable executive dysfunction in children with FASD, and that children with FASD may have more difficulty with executive functions in everyday life than is detected by laboratory-based tests alone.     

Comparisons of the BRIEF parental report and neuropsychological clinical tests of executive function in Fetal Alcohol Spectrum Disorders: data from the UK national specialist clinic

Extant literature is sparse with regards to the relationship between caregiver reports and neuropsychological tests of executive functioning in Fetal Alcohol Spectrum Disorders (FASD). The goal of this paper was determining the clinical utilities of executive functioning measures used in the United Kingdom national FASD clinic. We examined relationships between outcomes on the Behavior Rating Inventory of Executive Function (BRIEF) and the Delis-Kaplan Executive Function System (D-KEFS), as part of an ongoing service evaluation. Profiles of executive functioning measures were reported in order to contribute to delineating a profile of executive dysfunction in FASD. Caregivers of 49 people with FASD completed the Parent BRIEF, and 61 people with FASD were administered the D-KEFS. Pearson’s Correlations between all 11 BRIEF scales and the 18 selected D-KEFS subscales showed little relationship. The BRIEF showed a profile of clinically significant elevations in all three Index scores and seven out of the eight Scale scores. Several D-KEFS tests showed below average executive functioning. Both executive function measures have separate clinical utility in demonstrating executive function deficits in FASD. The sample population used in this study also show a similar pattern to FASD populations internationally, suggesting a similar neuropsychological profile is seen in the United Kingdom. However, caregiver reports display little relationship to neuropsychological tests. These measures likely monitor different aspects of executive functioning in different settings. Future research should focus on identifying tests that better relate findings from clinical settings to behavior in daily life.     

Children’s (in)ability to recover from garden paths in a verb-final language: Evidence for developing control in sentence processing

An eye-tracking study explored Korean-speaking adults’ and 4- and 5-year-olds’ ability to recover from misinterpretations of temporarily ambiguous phrases during spoken language comprehension. Eye movement and action data indicated that children, but not adults, had difficulty in recovering from these misinterpretations despite strong disambiguating evidence at the end of the sentence. These findings are notable for their striking similarities with findings from children parsing English; however, in those and other studies of English, children were found to be reluctant to use late-arriving syntactic evidence to override earlier verb-based cues to structure, whereas here Korean children were reluctant to use late-arriving verb-based cues to override earlier syntactic evidence. The findings implicate a general cross-linguistic pattern for parsing development in which late-developing cognitive control abilities mediate the recovery from so-called “garden path” sentences. Children’s limited cognitive control prevents them from inhibiting misinterpretations even when the disambiguating evidence comes from highly informative verb information.