Aerobic Fitness and Cognitive Development: Event-Related Potential and Task Performance Indices of Interference Control

1. Congruent Fz Reaction Time • Behavioral Measures • Accuracy • Participants responded more accurately to congruent (79.1%), compared to incongruent (71.2%), trials. • Higher fit participants (79.9%) responded more accurately than lower fit participants (70.3%). • Reaction Time • Participants responded more slowly to incongruent (532.8 ms), compared to congruent (507.9 ms), trials. • ERP Analysis • Component Latencies • Fitness effects were not evident for any ERP component latency. • Condition and Site effects were observed for the various components replicating previous research. • P1 Amplitude • A Fitness × Site interaction was observed, with higher fit participants exhibiting greater amplitude at Oz than lower fit participants. • A Condition effect was observed, with increased amplitude for congruent, compared to incongruent, trials. • A Site effect was observed, with Fz, Cz, and Pz exhibiting significantly less amplitude than Oz. • N1 Amplitude • A Site effect was observed, with findings indicating maximal amplitude at the vertex. • P2 Amplitude • A Fitness × Site interaction was observed, indicating higher fit participants exhibited larger amplitude than lower fit participants at Oz. • N2 Amplitude • A Condition effect was observed, with greater amplitude exhibited for incongruent, compared to congruent, trials. • P3 Amplitude • A Fitness × Site interaction was observed, indicating higher fit participants exhibited larger amplitude than lower fit participants at Pz. • A Site effect was observed, with the largest amplitude observed at Pz, and the smallest at Fz, with Cz and Oz falling in between. -5 600 Incongruent 0 500 -5 5 Amplitude (µV) 0 400 10 RT (ms) 5 15 300 Fz 10 20 Higher Fit Lower Fit 200 15 25 0 100 200 300 400 500 600 700 800 100 20 Higher Fit Lower Fit Amplitude (µV) 25 0 100 200 300 400 500 600 700 800 Accuracy 90 Cz Cz -5 * 0 80 -5 0 5 5 70 Accuracy (%) Amplitude (µV) Amplitude (µV) 10 10 60 15 15 50 20 20 25 25 40 0 100 200 300 400 500 600 700 800 0 100 200 300 400 500 600 700 800 Lower Fit Higher Fit -5 Pz P3 Amplitude at Pz 25 -5 5 Pz 0 20 0 Amplitude (µV) 10 Amplitude (µV) 5 15 10 15 20 Amplitude (µV) 15 25 0 100 200 300 400 500 600 700 800 10 20 Higher Fit Lower Fit 25 0 100 200 300 400 500 600 700 800 P1 Amplitude at Oz 20 Oz Oz -5 -5 0 0 15 5 5 Amplitude (µV) Amplitude (µV) 10 Amplitude (µV) 10 15 10 15 20 20 25 25 5 0 100 200 300 400 500 600 700 800 0 100 200 300 400 500 600 700 800 Higher Fit Lower Fit Time (ms) Time (ms) Aerobic Fitness and Cognitive Development: Event-Related Potential and Task Performance Indices of Interference Control in Preadolescent Children S. M. Buck, E. Osher, D. M. Castelli, & C. H. Hillman Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign Abstract Results Decreased participation in physical activity among children and adolescents has contributed to increased public health concerns. However, absent from these public health concerns is the relationship between physical inactivity and decrements in cognitive health in children. Thus, the relationship between aerobic fitness and interference control –one component of executive control– was investigated in 44 preadolescent children (Mage = 9.3 yrs; 21 females) who were grouped (i.e., higher-fit, lower-fit) according to their performance on a field test of aerobic capacity. Aerobic fitness was assessed using the PACER test of the Fitnessgram, and interference control was measured via event-related brain potential responses and task performance to congruent (e.g., HHHHH) and incongruent (e.g., HHSHH) conditions of a flanker task. Results indicated that higher-fit children performed more accurately across conditions of the flanker task when compared to lower-fit children, while group-differences were not observed for response speed. Further, P1 and P3 component amplitudes of the ERP were larger at Oz and Pz electrode sites, respectively, for higher- compared to lower-fit children across conditions of the flanker task. These findings indicate that fitness may be associated with early visual attention processes as well as the allocation of attentional resources to working memory during context updating; and suggest that aerobic fitness may non-selectively benefit cognitive function on tasks requiring variable amounts of interference control during preadolescent childhood. Participants Group means (SD) of demographic and fitness data for higher and lower fit participants. Conclusion Note. K-BIT is a composite score for IQ. SES = Socioeconomic Status. ADHD refers to scores on the ADHD Rating Scale V. The PACER and BMI are subscales of the Fitnessgram test. Normative values for the Fitnessgram may be found in Welk, G. J., J. R. Morrow, and H. B. Falls. Fitnessgram Reference Guide. Dallas, TX: The Cooper Institute, 2002. Values that share a common superscript are not significantly different at p < .05. In the current study, aerobic fitness was associated with better cognitive function in preadolescent children using a task that required variable amounts of interference control. Specifically, both higher and lower fit children exhibited the expected increase in RT and decrease in response accuracy to incongruent, relative to congruent, trials. However, higher fit children also exhibited better task performance compared to lower fit children, regardless of task condition. The neuroelectric data supported the fitness-related differences in task performance with increased amplitude observed for higher fit children at the P1, P2, and P3 components of the ERP across task conditions, suggesting greater processing of early visual attention and increased allocation of neural resources. Fitness was not associated with peak latency for any of the ERP components. These findings suggest that fitness may be beneficial to cognitive function for tasks involving variable amounts of executive control during preadolescent development. Method • Fitness Task • 291 children completed the Fitnessgram in a group setting. The Fitnessgram measures multiple aspects of physical fitness including aerobic capacity (i.e., PACER), muscle fitness (i.e., push-ups and curl ups), flexibility fitness (i.e., sit and reach), and body composition through height and weight measures that are converted to a body mass index (BMI) score. Children’s scores on the test of aerobic capacity (i.e., PACER) were ranked with recruitment coming only from the top and bottom 10% of the study sample. • Laboratory Procedure • K-BIT (Kaufman & Kaufman, 1990) • ADHD Rating Scale V (DuPaul, Power, Anastopoulos, & Reid, 1998) • Demographic Questionnaire • EEG activity was measured from twenty-eight midline and lateral Ag/AgCl electrodes in accordance with the 10-20 system (Jasper, 1958). • Cognitive Task • Participants completed congruent and incongruent conditions of the Eriksen flanker task (Eriksen & Eriksen, 1974), which required them to respond as quickly as possible to an array of letters. • Congruent trials were those in which the target letter was flanked by the same letter (i.e., HHHHH or SSSSS). • Incongruent trials were those in which the target letter was flanked by the opposing response letter (i.e., HHSHH or SSHSS). • Six blocks of 52 trials were administered with a 2-min rest period between blocks. Supported by UIUC Research Board Grant We thank the Champaign County School District for their assistance with participant recruitment.