Psychology (Functional Area: Developmental Science)

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Open Access
Transfer Success on the Linda Problem: A Re-Examination Using Dual Process Theory, Learning Material Characteristics, and Individual Differences
(2023-03-28) Truong, Michael; Stevens, Dale; Pathman, Jeni
The Linda problem is an intensely studied task in the literature for judgments where participants judge the probability of various options and frequently make biased judgements known as conjunction errors. Here, I conceptually replicated and extended the finding by Agnoli and Krantz (1989) that when participants are explicitly trained with Venn diagrams to inhibit their heuristics, successful transfer of learning is observed. I tested whether transfer success was maintained: (1) when the purpose of the training was obscured; (2) after controlling for individual differences; and (3) when learning materials did not include visual images. I successfully replicated their finding, identifying transfer success when the purpose of the training was masked and after controlling for individual differences. Furthermore, the effects of individual differences on transfer success depends on both the kind of learning material used and whether the purpose was masked. Hence, these findings support claims that education can inhibit biases.
Open Access
Does Mother's Early Talk Impact Children's Inclusion of Time and Space Details in their Autobiographical Narratives? A 12- Year Longitudinal Study
(2022-12-14) Virk, Tarnpreet Kaur; Pathman, Thanujeni
In this longitudinal study we examined the developmental trajectory of children’s inclusion of WHEN (temporal) and WHERE (spatial) details in their autobiographical memory narratives from early childhood (25-, 40, and 65-months) into adolescence (12-years-old) and investigated the factors that led to this development. Results showed that children’s inclusion of time and space details were statistically significant over time, with development for time being steeper than development for space. Mother’s inclusions of time, but not space, details were significant over the early childhood period. Mother’s early inclusions of time, but not space, details were a predictor of children’s future talk for time. Conventional time knowledge task performance was also correlated with children’s future inclusions of time information. This is the first longitudinal study to examine children’s inclusion of time and space details across childhood and into adolescence, and to examine how early factors in childhood could predict future narrative behaviour.
Open Access
Adults' long term memory as a function of birth experience
(2022-12-14) Au, Kar Yin Michelle; Adler, Scott A.
The growing rate of caesarean-section births has aroused concerns as it has shown to be associated with increasing biological and neurodevelopmental risks, but whether such neurodevelopmental impacts manifest behaviorally remain questionable. With studies demonstrating an attentional disruption in c-section-delivered infants and adults, similar effects are hypothesized to filter up the cognitive processing stream to memory function. The current study, therefore, aims to examine the birth experience effect on adults’ long-term memory. Vaginal-delivered and c-section-delivered adults participated in a two-day, memory-based visual search task. Results revealed that the two birth groups exhibited similar long-term memory retention and discrimination. However, memory differences might have been limited due to testing at a single retention interval as differences might manifest over longer intervals. Nonetheless, this finding suggests a negligible birth experience impact on adult’s long-term memory. Whether birth experience affects specific memory pathways and early memory development, as well as affecting memory differentially by c-section types, are yet to be examined.
Open Access
Effects of Birth Experience on Relational Memory in Adults
(2022-12-14) Ravi, Aarthi; Pathman, Thanujeni; Adler, Scott
Recent evidence has emerged that being born via planned or emergency cesarean section delivery (CSD) compared to vaginal delivery (VD) not only led to slower allocation of attention in human infants and adults but also affected hippocampal regions responsible for memory in mice. This is concerning as the number of C-sections has risen in the past two decades according to the World Health Organization. Therefore, the current study investigated if a higher-order cognitive function like relational memory, is also affected by CSD and if these effects last into adulthood. Birth experience effects on item-item, item-space and item-time relational memory along with item recognition were assessed in adult participants using a task developed by Konkel et al. (2008). Results indicated that the item-item memory performance was affected by CSD with planned CSD adults showing poorer recognition compared to emergency CSD adults. No differences in memory performance were found between either of the CSD groups and the VD group in any of the relational conditions. As relational binding has implications in forming autobiographical memories and connections between our past, present and future states, healthcare professionals should discuss with expecting mothers the potential long-term effects of planned CSD on their infants’ cognitive development.
Open Access
The Effect of C-Section Birth on Attention Task Performance and Cortical Grey Matter Integrity
(2022-03-03) Chevalier, Owen Michael Lane; Stevens, Dale; Adler, Scott
Past evidence suggests that Caesarean section (C-section) birth is a factor in reduced performance on visual attention tasks, as well as altered intrinsic functional neural networks, for both infants and adults born via C-section. The present study tested C-section and vaginally born adults on six tasks: a visual search task, the Attention Network Task, the Sustained Attention to Response Task, the Stroop Task, the Trail Making Test, and an n-back task. Adults born via C-section were less accurate on target-absent conditions in the visual search task. No other tests showed significant differences based on birth method. Additionally, whole-brain voxel-based morphometry analysis was conducted on the anatomical magnetic resonance imaging data of adults to identify potential effects of C-section birth on cortical grey-matter integrity. Findings suggest that there is an effect of C-section birth on top-down attention but were not significant for other hypotheses in the experiment and MRI analysis.
Open Access
Phonemic Discrimination and Eye-Movements in Infants
(2022-03-03) Bach-Kay, Shir; Adler, Scott A.
The ability to discriminate between different phonemes is a crucial part of language development in the first year of life. While language acquisition is a process that has been studied in both infants and adults in the past, the paradigms that were used to study this sensitive process have a number of shortcomings. To overcome these shortcomings, the present study examined 6-month-old infants' ability to discriminate between two different phonemes by means of an eye-tracking task, the Visual Expectation Cueing Paradigm (VExCP). In this paradigm, one randomly presented phoneme (paired with a central visual stimulus) predicted a visual target on the right side of a monitor screen and the other randomly presented phoneme predicted a visual target on the left side of the screen. If the infants could discriminate between the different phonemes then they would be able to correctly make anticipatory eye movements to the target location at a rate above chance. Results indicated that 6-month-old infants successfully discriminated between the two different phonemes forming an expectation for the phoneme-target location relations, and thereby making correct anticipatory eye-movements to the correct target location at a rate greater than chance. The findings indicate that the VExCP is an appropriate paradigm for the study of phonemic discrimination while overcoming the weaknesses of previously used paradigms.
Open Access
Assessing Context in Emotion Regulation: Validating the Difficulties in Interpersonal Regulation of Emotion (DIRE) Scale and Its Use in Measuring Emotion Regulation Variability
(2022-03-03) Girma, Fenote Selam; Rawana, Jennine
As research into emotion regulation (ER) expands, it is important to empirically account for contextually relevant aspects of interpersonal emotion regulation (IER). This study aimed to validate the Difficulties in Interpersonal Emotion Regulation (DIRE) scale, a new measure of interpersonal emotion dysregulation and examine its relationship to measures of psychopathology and well-being across three contexts (i.e., task, romantic, social). We also explored the utility of using the scenario-based structure of the DIRE scale to develop an ER variability score that would capture the number of strategies a person accesses between- and within-contexts. A test of the DIRE scale resulted in adequate model fit and validated its factor structure. DIRE scales were associated with emotion dysregulation, depression, and well-being. ER variability scores showed associations with emotion dysregulation and depression. These findings demonstrate the strong validity of the DIRE measure and underscore the importance of including situational contexts in IER research.
Open Access
Examining the Influence of Semantic Knowledge on Episodic Memory
(2021-11-15) Kian, Tida; Pathman, Thanujeni
Memory is a critical capacity for everyday life. Memory is not one process but consists of different systems (Robertson & Khler, 2007). Semantic memory is memory for general knowledge about the world and episodic memory is memory for a specific event from a particular time and place in the past (Tulving, 1972, 1983). Tulving (1972) referred to these systems as two separated but partially related memory systems. However, relatively little is known about how these two systems relate. Specifically, the influence of semantic memory on episodic memory is not fully understood. This study investigated the influence of semantic memory on memory for events (actions) and their spatial locations. The final sample for this study included 73 participants. Participants were divided into two groups that varied in the delay they experienced between the encoding phase and retrieval phase (immediate group, n=37; delay group, n=36). During the encoding phase, participants were presented with images of cartoon characters completing an action along with an image of a background scene (i.e., locations) that either matched the action (congruent trial), did not match the action (incongruent trial) or an action that could be performed in any location (neutral trial). During the retrieval phase, participants were presented with actions and asked whether the action was old or new (old/new recognition memory) and, if old, asked to choose the background image that went with that action (spatial location) among a group of distractors. Across delay, participants more accurately identified the locations for the congruent actions compared to the locations for the incongruent actions. Across conditions, participants in the immediate group more accurately identified the actions and spatial locations compared to the delay group. Further, different patterns for the types of errors participants made were observed. This study adds to our knowledge about the influence of semantic memory on episodic memory. Future studies can expand the research to different settings (e.g., naturalistic environments) and with more variable samples (e.g., different age groups).
Open Access
Bilingualism as a Proxy of Cognitive Reserve
(2021-11-15) Berkes, Matthias Daniel; Bialystok, Ellen
Previous studies have reported bilingualism to be a proxy of cognitive reserve (CR) based on evidence that bilinguals express dementia symptoms ~4 years later than monolinguals yet present with greater neuropathology at time of diagnosis when clinical levels are similar. This dissertation presents two studies that provide further evidence for the contribution of bilingualism to CR. The first study uses a novel brain health matching paradigm. Forty cognitively normal bilinguals with diffusion-weighted magnetic resonance images recruited from the community were matched with monolinguals drawn from a pool of 165 individuals in the Alzheimers Disease Neuroimaging Initiative (ADNI) database. White matter integrity was calculated for all participants using fractional anisotropy, axial diffusivity, and radial diffusivity scores. Propensity scores were obtained using white matter measures, sex, age, and education as predictive covariates, and then used in one-to-one matching between language groups, creating a matched sample of 32 participants per group. Matched monolinguals had poorer clinical diagnoses than that predicted by chance from a theoretical null distribution, and poorer cognitive performances than matched bilinguals as measured by scores on the MMSE. The findings support the interpretation that bilingualism acts as a proxy of CR such that monolinguals have poorer clinical and cognitive outcomes than bilinguals for similar levels of white matter integrity even before clinical symptoms appear. The second study examines the role of biomarkers and genetic factors associated with Alzheimer disease in a sample of 641 individuals from the ADNI database. Gradient boosted regression modelling was used to examine the influence of 10 predictive factors on clinical diagnosis in 3 different models. Weighted propensity scores were applied to analyses of white matter integrity and cognitive performance between clinical groups in two models and between language groups in one model. Analyses revealed a strong influence of biomarkers and genetic factors on clinical diagnosis in monolingual participants, but underrepresentation of bilingual participants in the sample limited interpretations of the findings between language groups. The results of the second study indicate that information about biomarkers and genetic factors improves analyses exploring the role of CR on dementia outcomes.
Open Access
Socio-Economic Status Scale Validation Study
(2020-11-13) Rowlin, Vanessa; Wiseheart, Melody Sunshine
The present study is investigating the validity and reliability of a new socioeconomic scale called the Wiseheart Socioeconomic Scale (WSESS). This new scale measures socioeconomic status (SES), as well as sociodemographic factors, including wealth, social supports and life stressors through the addition of eight novel WSESS subscales. Participants were recruited to investigate whether (1) the novel WSESS subscales were internally consistent; and (2) whether the WSESS novel subscales had acceptable levels of construct validity by comparing them to existent questionnaires. The results of the present study provide strong support for the internal consistency for the WSESS subscales. The WSESS subscales demonstrated either weak or weak-to-moderate correlations to either both or one of their associated criterion measures. Further tests are needed to evaluate different types of reliability and validity, and towards the production of a shorter version. This scale has implications for research, policy design, and in the therapeutic setting.
Open Access
Examining the Time Course of Attention in Monolinguals and Bilinguals
(2020-08-11) Chung-Fat-Yim, Ashley Kim; Bialystok, Ellen B.
There is converging evidence demonstrating that lifelong experience managing multiple languages on a regular basis has consequences for both language and cognition. Across the lifespan, bilinguals tend to outperform monolinguals on tasks that require selective attention. Compared to studies on children and older adults, these effects are less consistently observed in young adults. The majority of the research with young adults use relatively simple tasks that yield fast reaction times and accuracy rates at ceiling. In addition, these measures capture the endpoint of a chain of dynamic cognitive processes. Hence, the goal of the dissertation was to integrate two time-sensitive methodologies, mouse-tracking and eye-tracking, to examine whether monolinguals and bilinguals differ in the processes engaged between the time a response is initiated to when a response is selected. To assess cognitive performance, young adult and older adult monolinguals and bilinguals were administered the global-local task and oculomotor Stroop task while their eye-movements and mouse-movements were recorded. Both tasks involved focusing on one feature of the stimulus, while ignoring the other feature. When standard analyses of mean reaction time and accuracy were performed, no differences between language groups were observed in either age group. The mouse-tracking measures revealed that similar to experts, young adult bilinguals were slower to initiate a response than young adult monolinguals, while older adult bilinguals had a higher maximum velocity than older adult monolinguals. By using time-sensitive methodologies, we gain a deeper understanding of the cognitive processes associated with attention that are impacted by bilingualism during decision-making.
Open Access
Differential Attentional Responding by Planned and Emergency Caesarean-Section Versus Vaginally Delivered Infants and Adults
(2020-05-11) Rahimi, Maryam; Adler, Scott A.
Search asymmetry occurs when feature-present targets are detected more easily than feature-absent targets, resulting in an efficient search (i.e. flat RT - set size function) for feature- present targets, but an inefficient search (i.e. increasing RT set size function) for feature-absent targets. Both 3-month-old infants and adults have been found to exhibit a search asymmetry when assessed with saccade latencies (Adler & Gallego, 2014). Additionally, caesarean-section delivered infants exhibit slower attention and saccadic latencies than those born vaginally (Adler & Wong-Kee-You, 2015). This study is designed to determine the relative effects of different birth experiences on attention and search asymmetry performance and whether differences persist in adulthood. Two different visual circular arrays were presented: feature-present target among feature-absent distractors (R among Ps) or feature-absent target among feature-present distractors (P among Rs) with array set sizes of 1, 3, 5, 8. Results indicated that infants and adults saccadic latencies were unaffected by set size in feature-present arrays, suggesting an efficient search. Both caesarean-section born infants and adults had slower saccadic latencies when compared to the vaginal groups. Interestingly, infants born via planned caesarean-section were slower when compared to an emergency caesarean-section. There were no differences in saccadic latencies, however, between emergency and planned caesarean-section adults, suggesting that any difference due to planned vs emergency caesarean-sections does not persist into adulthood. For feature absent targets, both infants and adults exhibited increasing saccadic latencies with set size, suggesting an inefficient search. These findings suggest that any caesarean-section birth influences bottom-up attention and requires greater reliance on top-down processing even into adulthood. Thus, the development of attentional mechanisms can be influenced by early birth experiences that also impact adulthood.
Open Access
Task Switching Over the Lifespan
(2020-05-11) D'Souza, Annalise; Wiseheart, Melody Sunshine
People often switch from one goal to another, in response to changing environmental demands. Task switching affords flexibility, but at a price. A robust switch cost ensues, whereby individuals are slower and less accurate when switching between tasks than when repeating tasks. The current dissertation investigated the factors that contribute to a switch cost, using an exceptionally large sample of over 25,000 individuals (ages 10 to over 65) collected online. Switch costs are interpreted as the duration of psychological processes that are recruited to shift between tasks. In Study 1, shifting a task took 576 ms (or 108%) longer than performing a single task. Shifting tasks resulted in a 34% immediate decrease in productivity. An additional 74% long-term decrease in productivity occurred from maintaining readiness for a shift, and for using a cue to select a task, both of which occur even without an actual shift taking place. The results show that the seemingly simple switch cost involves multiple processes. Understanding these processes is crucial to interpret how flexibility varies with age. In Study 2A, task switching process developed until adulthood and then declined, similar to general cognitive ability. However, each process changed differently with age. Findings show that decline is not simply development in reverse: The rate of decline in mid to late adulthood was up to 20 times slower than the rapid development in adolescence; Middle-aged adults were slower than young adults, but as accurate; They maintained less advance readiness but used contextual cues as well as their younger counterparts. In Study 2B, the effects of age were replicated in an independent sample using identical methodology. These findings highlight the usefulness of web-based data collection, effect size estimation, and segmented regression techniques.
Open Access
Judging the Credibility of Websites: An Effectiveness Trial of the Spacing Effect in the Elementary Classroom
(2019-11-22) Foot, Vanessa Lauren; Wiseheart, Melody Sunshine
Spaced learningthe spacing effectis a cognitive phenomenon whereby memory for to-be-learned material is better when a fixed amount of study time is spread across multiple learning sessions instead of crammed into a more condensed time period. In an educational context, this means that long-term retention is enhanced when students begin to review subject material several days leading up to a test instead of cramming right before the test. The spacing effect has been shown to be effective across a wide range of ages and learning materials, but no research has been done that looks at whether spacing can be effective in real-world classrooms, using real curriculum content, and with real teachers leading the intervention. The current study was the next step in determining whether spacing can and should be implemented across the curriculum. Lesson plans for teaching website credibility was distributed to homeroom elementary teachers with specific instructions on how to manipulate the timing of the lessons for either a massed (one-per-day) or spaced (one-per-week) delivery, and after one month, students were asked to apply their knowledge on a final test, where they evaluated two new websites. Students in the spaced condition remembered more facts from the lessons but showed no spacing advantage on the critical thinking measures where they had to explain their ratings in a paragraph. There was no difference in the actual rating scores during the lessons or at final test. These results indicate that when lesson plans are released to homeroom teachers, variability between teachers and classrooms may result in an overall reduction or elimination of a traditional spacing effect. Future recommendations for spacing studies are made.
Open Access
A Closer Look at the Effect of Bilingualism on Working Memory
(2019-11-22) Capani, Angela M.; Bialystok, Ellen B.
Previous research suggests that bilinguals act as experts when engaged in tasks requiring attentional control (Incera & McLennan, 2015). Experts across various domains are slower to initiate a response, but then produce a more efficient response. We used mouse-tracking to determine whether bilingual (n = 51) and monolingual (n = 51) young adults (M = 20.65) employed different strategies while engaged in two sets of memory tasks, the n-back and item/associative tasks. Language groups displayed similar performance on most tasks, however, bilinguals had longer initiation and reaction times than monolinguals on the associative task. When examined as a continuous factor, degree of bilingualism was positively correlated with initiation time. The results of the regression analysis support the conclusion that bilingualism impacts the strategies that participants display while completing memory tasks. In the future, tasks requiring more controlled processing should be utilized to allow for more robust differences to appear.
Open Access
Sentence Comprehension in Monolingual and Bilingual Children
(2019-03-05) Ostadghafour, Sarvenaz; Bialystok, Ellen B.
Abstract Bilingual children outperform monolingual children on non-linguistic tasks that tap executive function. It still unknown whether the enhancement of executive functioning found for bilingual children improves complex linguistic comprehension. The present study examined possible differences between monolingual and bilingual childrens sentence comprehension in the presence of different sources of information that conflicted with a correct interpretation.100 children (33monolinguals and 67 bilinguals) between the ages of 4- and 5-years old were examined on two complex linguistic tasks. The findings showed that bilingual children were more accurate than monolingual children in understanding the meaning of the spoken sentences in the presence of distraction. Bilingual childrens advanced attentional control skill has been proposed as a possible cause that led them to effectively focus their attention on the relevant information while ignoring other sources of information that interfered with the correct interpretation. Keyword: Bilingual children, Monolingual children, Executive function, Attentional Control, Sentence comprehension
Open Access
The Effect of Art Training on Dementia
(2019-03-05) Matthews, Katherine Gladys; Wiseheart, Melody Sunshine
The present study explores the effect of visual art training on people with dementia (PWD), utilizing a randomized control trial (RCT) design, with a structured usual activity waitlist control group, in order to investigate the effects of an eight-week visual art training program on PWDs cognition, mood, and behaviour. Cognition was assessed with: The Backward Digit Span, measuring verbal working memory; the Body Part Pointing Test, measuring visuospatial working memory; and the Montreal Cognitive Assessment (MoCA), measuring overall cognitive function. Mood and behaviour were qualitatively assessed based on volunteer-completed observational reports. The results of the study indicate that while cognition is not significantly affected by an eight-week art training program, mood and behaviour are positively impacted.
Open Access
Ecological and Cognitive Influences on Orangutan Space Use
(2019-03-05) Bebko, Adam Osborne; Russon, Anne E.
Many primates depend on resources that are dispersed non-uniformly. Primates able to encode the locations of such resources and navigate efficiently between them would gain a selective advantage. However, little is currently known about the cognitive mechanisms that help primates achieve this efficiency in the wild. The presence habitual route networks in some primate species suggests they may navigate using route-based cognitive maps for encoding spatial information. However, little is known about factors that influence where such route networks are established. Recent evidence of habitual route networks in wild orangutans makes them ideal candidates for examining factors that affect the establishment and use of such networks. I completed three studies using new methodology to examine ecological and cognitive factors that may affect habitual route networks in wild orangutans living in Kutai National Park, East Kalimantan, Indonesia. Results suggest that orangutan habitual route networks are likely the product of both local ecological considerations and how they cognitively encode and use spatial information. Results imply that the spatial configuration of habitual route networks may primarily be a product of local ecology, whereas how orangutans use them day-to-day may be a product of both local ecology and sophisticated cognitive strategies that may include cognitive maps. These studies demonstrate the utility of using modern mapping software and machine learning technology for applications in primate behavior and ecology.
Open Access
Putting the Distributed Practice Effect into Context
(2019-03-05) Weston, Christina; Wiseheart, Melody Sunshine
Spaced repetition leads to superior final memory relative to massed repetition, a phenomenon known as the distributed practice effect. However, when items are repeated in variable study contexts across learning opportunities (relative to a consistent study context), the advantage of distributed practice over massed practice is typically reduced. In this dissertation, the effect of study context on the distributed practice effect was investigated from a neural perspective (Study 1) and from a developmental perspective (Study 2). In Study 1, event-related potentials (ERPs) were recorded as participants learned stimuli repeated after massed or distributed lags on either a consistent or variable background. After a fixed retention interval, stimuli were presented for a third time and participants recognition memory was tested. Behavioural evidence of a Lag x Study Context interaction was mixed. The ERP data revealed a neural distinction between massed and distributed repetitions during the study phase in terms of the late positivity component (LPC); however, the LPC was not further defined by the study context manipulation. During the test phase, distributed, variably studied repetitions engendered the greatest neural familiarity response compared to all other repetition conditions. In Study 2, younger and older participants learned stimuli repeated after varying lags on either a consistent or variable background. The background scenes were either shared among all to-be-learned items (Experiment 2A) or unique to each to-be-learned item (Experiment 2B). After the study phase, participants free recall memory was tested. Although older adults had greater difficulty identifying whether a repeated items study context had changed throughout the study phase, as hypothesized, they still exhibited similar final recall performance to younger adults during the test phase. Comparing data from the two experiments, the results also revealed that variations to study context might actually enhance the distributed practice effect in certain learning situations. This enhancement effect, which warrants further investigation, might depend on the type of material being learned and/or the variety of contextual information available during study.
Open Access
Spatial Attention-Modulated Surround Suppression Across Development: A Psychophysical Study
(2019-03-05) Wong Kee You, Audrey Marie Beatrice; Adler, Scott A.
Several studies have demonstrated that surrounding a given spatial location of attentional focus is a suppressive field (e.g., Hopf et al., 2006). Though several studies have provided psychophysical (e.g., Cutzu & Tsotsos, 2003) and neural evidence of this effect in young adults (e.g., Boehler et al., 2009), whether this phenomenon is also observed in development was not fully known. Experiment 1 of the current study was therefore conducted to examine whether attention-modulated surround suppression was observed in younger age groups. Participants between the ages of 8 and 22 years were tested on a two-alternative forced choice task, in which their accuracy in discriminating between two red target letters among black distractor letters was measured. A spatial cue guided the participants attention to the upcoming location of one of the target letters. As would be predicted for the young adults, their accuracy increased as the inter-target separation increased, suggesting that visual processing is suppressed in the immediate vicinity of an attended location. Pre-adolescents (12 to 13 years) and adolescents (14 to 17 years) also exhibited attentional surround suppression, but intriguingly their inhibitory surround appeared to be larger than that of young adults. The 8- to 11-year-olds did not exhibit attentional suppression. In Experiment 2, when a central cue instead of a spatial cue was presented, surround suppression was no longer observed in an independent set of 8- to 27-year-olds, suggesting that the findings of Experiment 1 were indeed related to spatial attention. In Experiment 3, yet another independent group of 8- to 9-year-olds were tested on a modified version of the Experiment 1 task, where the cue presentation time was doubled to provide them with more support and more time to complete their top-down feedback processes. With this manipulation, attention-modulated surround suppression was still not observed in the 8- to 11-year-olds. Overall the current study findings suggest that top-down attentional feedback processes are still immature until approximately 12 years of age, and that they continue to be refined throughout adolescence. Protracted white matter maturation and diffuse functional connectivity in younger age groups are some of the potential underlying mechanisms driving the current findings.