Neurophenomenology: How to combine subjective experience with brain evidence
In this study we investigated whether refined first-person data from trained subjects could be used to guide the detection and interpretation of neural processes. This study is an attempt to implement a research program labeled « Neurophenomenology » (Varela, 1996). This style of research takes part to the recent interest in using introspective phenomenological reports […]
In this study we investigated whether refined first-person data from trained subjects could be used to guide the detection and interpretation of neural processes. This study is an attempt to implement a research program labeled « Neurophenomenology » (Varela, 1996). This style of research takes part to the recent interest in using introspective phenomenological reports phenomenology in studying brain basis of consciousness. Neurophenomenology takes the further step of incorporating ‘first-person methods’ —precise and rigorous methods subjects can use to increase the threshold of their awareness of their Neurophenomenology takes a the further step of incorporating ‘first-person methods’. experience from moment to moment, and thereby provide more refined first-person reports. The target is to create experimental situations that produce ‘reciprocal constraints’ between first-person phenomenological data and third-person cognitive-neuroscientific data: the subject is actively involved in generating and describing specific and stable, experiential or phenomenal categories; and the neuroscientist can be guided by these first-person data in the analysis and interpretation of the large-scale neural processes of consciousness.
The study of the variability of the brain responses constitutes an interesting empirical case for this approach. Indeed, even during well-calibrated cognitive tasks, successive brain responses to repeated, identical stimulations are highly variable. The source of this variability is believed to reside mainly in fluctuations of the subject’s cognitive ‘context’ defined by his/her attentive state, spontaneous thought-process, strategy to carry out the task, and so on. As these factors are hard to manipulate precisely, they are usually not controlled and the variability is treated as unintelligible noise which is discarded by averaging techniques. The description by the subject of subtle changes of cognitive context and subjective experience could thus guide the study of this variability.
Our strategy has thus consisted, firstly, to intensively train the subjects to perform the task. The purpose was to improve their perceptual discrimination and to enable them to carefully explore variations in their subjective experience during repeated exposure to the task. They were thus instructed to direct their attention to their own immediate mental processes during the task and to the We trained subjects to improvise their perceptual discrimination and to enable them to carefully explore variations in their subjective experience felt-quality of the emergence of the 3D image. In dialogue with the experimenters, they defined their own stable experiential categories or phenomenal invariants to describe the main elements of the subjective context in which they perceived the 3D shapes. Degree of preparation felt by the subject and the quality of his perception appeared as a common factor throughout the subjects.
After this training session, we recorded the subjects’ electrical brain activity (EEG) during this task and, after each trial, their own report about their cognitive context and visual experience. These first-person data were used to divide the trials into corresponding phenomenological clusters (PhC). Separate dynamical analyses were conducted for each cluster to determine the transient patterns of neural synchrony before and after the stimulus. The hypothesis was that distinct PhCs would be characterized by distinct ‘dynamical neural signatures’ (DNS) before stimulation (reflecting state of preparation), and that these DNSs would then differentially condition the neural and behavioral responses to the stimulus.
We found that 1) characteristic patterns of endogenous synchrony appeared in frontal electrodes before stimulation. These patterns depended on the degree of preparation and the immediacy of perception as verbally reported. 2) Although the precise shape of these synchrony patterns varied among subjects, these patterns were stable for several recordings and therefore seem to constitute a consistent signature of a subject’s cognitive strategy or aptitude to perform the perceptual task. 3) Preparatory states modulate both the behavioral performance and the evoked and induced synchronous patterns that follow.
These results stress the importance of gathering of first-person, phenomenological data from trained subjects as a heuristic strategy for investigating the neural dynamics of consciousness.
© A. Lutz
Author Information
Antoine Lutz is a postdoctoral researcher at the W.M. Keck Laboratory, University of Wisconsin-Madison.
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References
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First-person reports/data method is of most importance for neuroscientific researches. Nonetheless, such a style, whose main field is “introspective phenomenology in studying brain basis of consciousness” has more than one shortcoming. I argue that training itself is a remarkable one, and to get rid of some of the weaknesses is to use data from untrained participants, at least for comparison. Good luck.