PhD defence

From Noise to Insight: The Functional Role of BOLD Signal Variability and Aperiodic Neural Activity in Metacontrol

• C. Zhang

Date

Thursday 4 July 2024

Time

15:00 - 15:45 hour

Address

Academy Building
Rapenburg 73
2311 GJ Leiden

Supervisor(s)

• Prof.dr. B. Hommel
• dr. A. Ghosh

Summary

Ever wondered why some people stick to a fixed exercise routine no matter what, while others adjust their workouts based on fatigue or boredom, trying different activities to stay engaged? What drives this difference in behavior? And what brain activity underlies these differences?

This thesis explores the role of what has traditionally been considered as neural “noise”, specifically BOLD signal variability and aperiodic neural activity, in human cognitive functions, particularly in metacontrol. The metacontrol model assumes that individuals vary in their cognitive styles between "persistence" and "flexibility." Persistence emphasizes focused goal pursuit, while flexibility allows for easy task switching and consideration of diverse possibilities.

Through three empirical studies, this thesis identifies associations between two specific forms of neural "noise" – BOLD signal variability and aperiodic neural activity – and metacontrol biases (i.e., persistence vs. flexibility). The first study underscores the importance of resting-state BOLD signal variability in understanding individualized cognitive control styles. The second study highlights the importance of the aperiodic component of the EEG power spectrum in reflecting demand-specific metacontrol states. Notably, the third study illuminates the functional significance of aperiodic activity in creative thinking.

Overall, the research presented in this thesis highlights the importance of resting-state BOLD signal variability and aperiodic activity in the EEG power spectrum for understanding the neural underpinnings of cognitive functions.

PhD dissertations

Approximately one week after the defence, PhD dissertations by Leiden PhD students are available digitally through the Leiden Repository, that offers free access to these PhD dissertations. Please note that in some cases a dissertation may be under embargo temporarily and access to its full-text version will only be granted later.

Press enquiries (journalists only)

[phone]
[e-mail]

General information

Beadle's Office
[e-mail]
[phone]