Title Information
Title
Fractal Scaling in Heart Rate Variability Dynamics in Relation to Cognitive Load
Abstract
Heart Rate Variability (HRV) is examined in studies of exercise physiology and general medicine. It reflects the balance between the parasympathetic and sympathetic systems of the autonomic nervous system. HRV can be summarized using simple statistics (e.g. standard deviation), but has also been quantified by fractal scaling, a mathematical term that describes patterns observable across varying scales along which it is viewed. HRV typically decreases with increasing physical demands which is thought to reflect diminishing adaptability. Here, we test our hypothesis that fractal scaling and HRV correlate systematically with increasing cognitive demands. Detrended Fluctuation Analysis (DFA) is used to determine the dynamics of fractal scaling in heart rate with increasing cognitive load. DFA is a key statistical method used to analyze scaling behavior in time series. DFA can quantify scaling behavior in physiological systems (e.g. neuronal and cardiovascular), and demonstrate long-range temporal correlations therein. When the variability of inter-beat intervals scales increases linearly (in log-log space) with the number of beats over the window in which variability is measured, HRV exhibits fractal scaling. In contrast, when they become more random or more correlated, fractal scaling breaks down. Physiologically, this may be due to the withdrawal and reallocation of the vagal control (mediated by the vagus nerve) toward other immediate mental or physical demands. Vagal withdrawal may explain why decreasing HRV is associated with diminished adaptability. To explore the relationship between HRV and cognitive load, we utilize DFA to determine the fractal scaling dynamics in heart rate with increasing cognitive load. We test the prediction that fractal scaling in HRV both varies systematically with cognitive load and also correlates with individual differences in the fractal scaling of reaction times. We also test the prediction that fractal scaling in heart rate correlates with individual differences in subjective cognitive effort during task performance. Finally, because fractal scaling in neuronal oscillations has been shown to correlate with fractal scaling in behavior (both quantified by DFA), on-going work will test the hypothesis that diminished fractal scaling in HRV correlates with reduced fractal scaling in EEG signal and cognitive flexibility in demanding mental tasks.
Name: Personal
Name Part
Tran, Lily
Role
Role Term: Text
creator
Name: Personal
Name Part
Andrew Westbrook
Role
Role Term: Text
advisor
affiliation
Brown University. CLPS
Name: Corporate
Name Part
Brown University. Undergraduate Teaching and Research Awards
Role
Role Term: Text
research program
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01036509")
Topic
Neurosciences
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/00866540")
Topic
Cognitive neuroscience
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01423727")
Topic
Statistics
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/00872004")
Topic
Computational neuroscience
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/00850724")
Topic
Central nervous system
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/00953705")
Topic
Heart beat
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/00933510")
Topic
Fractals--Data processing
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01151192")
Topic
Time-series analysis--Data processing
Language
Language Term: Text (ISO639-2B)
English
Type of Resource (primo)
text_resources
Genre (aat)
posters
Origin Information
Place
Place Term: Code (MARC Country Code)
riu
Place
Place Term: Text
Providence, RI
Publisher
Brown University
Date Created (keyDate="yes", encoding="w3cdtf")
2022
Physical Description
Extent
1 poster
digitalOrigin
born digital
Access Condition: use and reproduction
All rights reserved
Access Condition: rights statement (href="http://rightsstatements.org/vocab/InC/1.0/")
In Copyright
Access Condition: restriction on access
All Rights Reserved
Identifier: DOI
10.26300/c1fp-2019