Experiencing your brain: neurofeedback as a new bridge between neuroscience and phenomenology

Abstract

Neurophenomenology is a scientific research program aimed to combine neuroscience with phenomenology in order to study human experience. Nevertheless, despite several explicit implementations, the integration of first-person data into the experimental protocols of cognitive neuroscience still faces a number of epistemological and methodological challenges. Notably, the difficulties to simultaneously acquire phenomenological and neuroscientific data have limited its implementation into research projects. In our paper, we propose that neurofeedback paradigms, in which subjects learn to self-regulate their own neural activity, may offer a pragmatic way to integrate first-person and third-person descriptions. Here, information from first- and third-person perspectives is braided together in the iterative causal closed loop, creating experimental situations in which they reciprocally constrain each other. In real-time, the subject is not only actively involved in the process of data acquisition, but also assisted to directly influence the neural data through conscious experience. Thus, neurofeedback may help to gain a deeper phenomenological-physiological understanding of downward causations whereby conscious activities have direct causal effects on neuronal patterns. We discuss possible mechanisms that could mediate such effects and indicate a number of directions for future research.

Keywords: downward causation; multiscale neural dynamics; neurofeedback; neurophenomenology; voluntary action.

FIGURE 1

Loop of online data streaming during Neurofeedback. (A) Signals from scalp-, macro-, and/or microelectrodes are pre-amplified locally and sent to the acquisition system. (B) All electrodes are recorded and stored on the local computer. (C) Data is read by another device, where online analysis is performed (frequency filtering, spike detection, spike sorting) in time bins of 0.5 s. (D) Processed data is presented to the subject in form of a graphical, moving object, or sound changing in frequency according to the recorded activity. (E) Subject controls the graphical object by influencing his brain activity through subjective experience.

FIGURE 2

Multiscale interaction. The macro-, meso-, and microscopic processes are braided together by co-occurring multifrequency oscillations, giving rise to upward and downward causation. Activity at micro-scale (cellular assemblies) sums up to local activities at meso-scale, which in turn gives rise to large-scale dynamics and result in a conscious event. In opposite way, cognitive effort influences global brain oscillations in the low- frequency range, which constrain local oscillations in the high-frequency range by variations of the underlying neuronal excitability. These high-frequency oscillations determine the probability of occurrence of spikes and their temporal coincidences on the millisecond scale.

FIGURE 3

Multiscale recordings. (A) Scalp-electrode (green), clinical multi-contact macro-electrode (red), and micro-electrode emerging from the tip of the macro-electrode (resolution: volume <1 mm³ on a millisecond scale). Such recording setups are used for presurgical evaluation in epilepsy. (B) Signal from scalp-, macro-, and micro electrode in green, red, and blue, respectively. Lower three traces show micro-electrode recordings filtered in the gamma band, with applied high-pass filter above 500 Hz and sorted spikes for different neurons. Note the high-frequent activity present in the micro-electrode recording, which is not visible in the signal from macro- or scalp-electrodes.