Triana AM, et al. (2024)
PLoS Biol 22(10): e3002797.
Abstract
Our behavior and mental states are constantly shaped by our environment and experiences. However, little is known about the response of brain functional connectivity to environmental, physiological, and behavioral changes on different timescales, from days to months. This gives rise to an urgent need for longitudinal studies that collect high-frequency data. To this end, for a single subject, we collected 133 days of behavioral data with smartphones and wearables and performed 30 functional magnetic resonance imaging (fMRI) scans measuring attention, memory, resting state, and the effects of naturalistic stimuli. We find traces of past behavior and physiology in brain connectivity that extend up as far as 15 days. While sleep and physical activity relate to brain connectivity during cognitively demanding tasks, heart rate variability and respiration rate are more relevant for resting-state connectivity and movie-watching. This unique data set is openly accessible, offering an exceptional opportunity for further discoveries. Our results demonstrate that we should not study brain connectivity in isolation, but rather acknowledge its interdependence with the dynamics of the environment, changes in lifestyle, and short-term fluctuations such as transient illnesses or restless sleep. These results reflect a prolonged and sustained relationship between external factors and neural processes. Overall, precision mapping designs such as the one employed here can help to better understand intraindividual variability, which may explain some of the observed heterogeneity in fMRI findings. The integration of brain connectivity, physiology data and environmental cues will propel future environmental neuroscience research and support precision healthcare.
Here are some thoughts:
This innovative longitudinal study investigates the dynamic relationship between brain functional connectivity and various environmental, physiological, and behavioral factors over a 133-day period. By employing a precision mapping approach focused on a single individual, the researchers collected high-frequency data using fMRI scans, smartphones, and wearables.
The study reveals that brain connectivity is significantly influenced by external factors such as sleep, physical activity, and physiological states, with these effects extending up to 15 days in the past. This research is particularly important for psychologists as it highlights the need to consider environmental and lifestyle factors when studying brain function and behavior.
The longitudinal design provides valuable insights into intraindividual variability, often overlooked in group-level studies. By integrating multiple data sources, the study demonstrates the potential for a more comprehensive understanding of brain-behavior relationships. The findings have implications for research methodology, suggesting that recent behavioral and physiological patterns should be considered as potential confounds in fMRI studies. Additionally, the study's approach and findings are relevant to understanding and monitoring mental health disorders. The openly accessible dataset and the potential for using wearables and smartphones as cost-effective monitoring tools open up new avenues for research and clinical applications in psychology and neuroscience.
