Results for Oculomotor Performance Flashcards
What were the main effects for reaction time (RT) found in your study?
I found main effects for time, p < .001, ηp2 = 0.57 (large), task, p < .001, ηp2 = 0.79 (large), and group, p = .03, ηp2 = 0.14 (large).
What interactions for reaction time (RT) were observed in your study?
I observed interactions involving time by task, p < .001, ηp2 = 0.32 (large), time by group, p = .03, ηp2 = 0.16 (large), and group by time by task, p = .04, ηp2 = 0.12 (large).
How did prosaccade and antisaccade reaction times (RTs) differ in your study?
Prosaccade RTs (235 ms, SD = 35) were generally shorter than antisaccade RTs (292 ms, SD = 38), reflecting the underlying neural processes (57 ms difference)
Prosaccade planning is mediated by direct retinotopic maps in the superior colliculus with minimal top-down executive function (EF) involvement (Wurtz & Albano, 1980).
Antisaccade planning times reflect the time-consuming EF demands of inhibitory control and vector inversion (Munoz & Everling, 2004).
What did your study find regarding pre-exercise reaction times (RTs) for prosaccades between the SRC and HC groups?
I found that pre-exercise RTs for prosaccades did not differ between the SRC and HC groups. This finding was expected, as prosaccades are pre-potent and implemented independently of top-down executive function (EF) (Johnson et al., 2015a; 2015b; Webb et al., 2018).
How did the pre-exercise antisaccade RTs differ between the SRC and HC groups?
I found that pre-exercise antisaccade RTs were significantly longer for the SRC group compared to the HC group, p < .001, dz = -1.26 (large)
Are your RT findings consistent with previous oculomotor studies on RTs and directional errors in individuals with SRC?
Yes, my findings are consistent with previous oculomotor studies demonstrating that individuals with an SRC exhibit longer antisaccade reaction times (RTs) and/or more directional errors compared to age- and sex-matched healthy controls within 7 days and 14–30 days post-injury (Ayala & Heath, 2020; Webb et al., 2018; Johnson et al., 2015a; 2015b)
How does the magnitude of the pre-exercise between-group antisaccade RT difference in this study compare to previous findings?
The magnitude of the between-group antisaccade RT difference (i.e., 42 ms) is similar to the 40 ms and 44 ms differences reported by Johnson et al. (2015b; <7 days post-injury) and Ayala and Heath (2020; <12 days post-injury), respectively.
- What do your results suggest about the effect of exercise on pro- and antisaccade RTs for both SRC and HC groups in your study?
The results suggest that exercise led to a decrease in antisaccade RTs for both SRC and HC groups, ps <.001, dz = 1.5 and 1.09 (large), while prosaccade RTs remained unchanged, ps >.22, dz = 0.32 and 0.27 (small).
Postexercise antisaccade RTs did not significantly differ between the SRC and HC groups, p = .31, dz = -0.37 (small).
Was there a between-group difference in the magnitude of decrease in antisaccade RTs pre-to-postexercise?
The SRC group had a significantly larger magnitude of decrease in antisaccade RTs pre-to-postexercise (51.33, SD = 34) versus (19.84, SD = 18) respectively.
How do you account for the null pre- to postexercise change in prosaccade RTs?
The null pre- to postexercise change for prosaccade RTs is accounted for by their pre-potent nature (Wurtz & Albano, 1980) and demonstrates that an exercise intervention does not result in a general improvement in information processing.
How does your finding regarding the postexercise antisaccade RT reduction compare to previous research in healthy adults and persons at risk for cognitive decline?
The postexercise antisaccade RT reduction supports a number of studies by our group (Dirk et al., 2020; Heath et al., 2018; Petrella et al., 2019; Samani & Heath, 2018; Shukla & Heath, 2022) and others (Zhou & Bai, 2023; Zhou & Zhuang, 2023) reporting that healthy adults (young and older) and persons at risk for cognitive decline (Heath et al., 2016; 2017) elicit a selective postexercise executive function (EF) benefit (for an extensive review, see Zou et al., 2023).
- How can you be sure that the antisaccade RT reduction is not related to a practice-related performance benefit?
The antisaccade RT reduction has been shown to be independent of a practice-related performance benefit, given that frequentist and Bayesian analyses report that antisaccade RTs are equivalent when interspersed by a non-exercise control interval (Dirk et al., 2020; Dyckman & McDowell, 2005; Klein & Berg, 2001; Samani & Heath, 2018; Shukla & Heath, 2022; Tari et al., 2020, 2023).
- Did the postexercise antisaccade RT reduction come at the cost of decreased endpoint accuracy (i.e., a speed-accuracy trade-off)?
No, antisaccade durations and gain variability did not vary across pre- to postexercise assessments, indicating that the postexercise RT reduction was not related to an implicit or explicit control strategy designed to decrease RT at the cost of decreased endpoint accuracy (i.e., speed-accuracy trade-off) (Fitts, 1954).
How do your findings contribute to the existing literature on the effects of a single bout of exercise on executive function?
My findings align with previous literature reporting that a single bout of exercise provides a selective EF benefit (for meta-analyses, see Chang et al., 2012; Lambourne & Tomporowski, 2010; Ludyga et al., 2016; Zou et al., 2023).
Most notably, I believe our results add importantly to the literature insomuch as they provide a first demonstration that persons with an SRC exhibit an EF benefit following a single bout of sub-symptom threshold aerobic exercise.
Based on Figure 3, What are the key takeaways regarding RTs and difference scores?
- The red squares represent the group means for the SRC group, while the green triangles represent the group means for the HC group.
- The error bars indicate the 95% confidence intervals for the between-participant variability.
- The offset panels show the mean RT differences between post- and pre-exercise for each group.
- If the error bars don’t cross the zero line, it indicates a reliable difference in RTs.
- Prosaccade RTs were generally shorter than antisaccade RTs. Before exercise, the sport-related concussion group had significantly longer antisaccade RTs compared to the healthy control group, but there was no difference in prosaccade RTs between the two groups.
- After exercise, the difference in antisaccade RTs between the two groups disappeared, suggesting that exercise had a greater effect on the sport-related concussion group, bringing their performance closer to that of the healthy control group.
- When comparing the change in RTs after exercise (post-exercise minus pre-exercise), prosaccade RTs did not change significantly for either group. However, antisaccade RTs decreased significantly after exercise for both groups, with a more pronounced decrease in the sport-related concussion group.
- In conclusion, the study suggests that exercise may have a beneficial effect on antisaccade performance, especially for individuals with sport-related concussions, while prosaccade performance remains relatively unaffected by exercise in both groups.
