FIGURE 3.

Interrelation between strategy and mean O₂Hb amplitudes in left prefrontal channels over the course of eight NIRS based neurofeedback sessions in each individual subject on a descriptive level (A–M). O₂Hb amplitudes are exemplarily illustrated only for the left hemisphere as amplitudes on the right hemisphere exhibited similar patterns. For qualitative analysis on a descriptive level of interrelations between amplitude and strategy at the group level, amplitudes were z-transformed (N). VFT, verbal fluency task.