Self-regulation of visual word form area activation with real-time fMRI neurofeedback

Abstract

The Visual Word Form Area (VWFA) is a key region of the brain's reading network and its activation has been shown to be strongly associated with reading skills. Here, for the first time, we investigated whether voluntary regulation of VWFA activation is feasible using real-time fMRI neurofeedback. 40 adults with typical reading skills were instructed to either upregulate (UP group, N = 20) or downregulate (DOWN group, N = 20) their own VWFA activation during six neurofeedback training runs. The VWFA target region was individually defined based on a functional localizer task. Before and after training, also regulation runs without feedback ("no-feedback runs") were performed. When comparing the two groups, we found stronger activation across the reading network for the UP than the DOWN group. Further, activation in the VWFA was significantly stronger in the UP group than the DOWN group. Crucially, we observed a significant interaction of group and time (pre, post) for the no-feedback runs: The two groups did not differ significantly in their VWFA activation before neurofeedback training, but the UP group showed significantly stronger activation than the DOWN group after neurofeedback training. Our results indicate that upregulation of VWFA activation is feasible and that, once learned, successful upregulation can even be performed in the absence of feedback. These results are a crucial first step toward the development of a potential therapeutic support to improve reading skills in individuals with reading impairments.

Figure 1

Experimental design. After an initial screening, participants underwent a set of behavioral tests on cognition and reading skills. During the MR session, participants first underwent a functional VWFA localizer, a T1-weighted anatomical scan, and a no-feedback run. Then, 6 runs of neurofeedback training were performed, followed by a break outside the scanner. After the break, participants repeated the no-feedback and functional localizer run in the MR scanner and the reading performance tests outside the scanner.

Figure 2

Neurofeedback paradigm. During neurofeedback runs, participants were instructed to either upregulate (UP group) or downregulate (DOWN group) their visual word form area activation using mental strategies. To prevent them from thinking about reading-related strategies during other times, participants were instructed to mentally play tennis during baseline blocks that were interleaved with the regulation blocks.

Figure 3

Whole brain activation during neurofeedback runs in the UP group as compared to the DOWN group. When comparing the regulation versus baseline contrast between the two groups, we observed significant (FWE-corrected p < 0.05) clusters in the left superior temporal gyrus (STG), the left inferior frontal gyrus (IFG), the left precentral gyrus (PCG), the cerebellum, orbitofrontal cortex (OFC), cuneus, and the supplementary motor area (SMA). The literature-based mask of the VWFA is depicted in green.

Figure 4

Visual word form area activation during neurofeedback training. We observed a significant difference in VWFA activation during neurofeedback training (mean activation over all six neurofeedback runs) between the UP and DOWN group. Mean values and error bars (depicting one standard error) are displayed on the right side of the boxplots.

Figure 5

Visual word form area activation during no-feedback runs before and after neurofeedback training. We observed a significant interaction effect between the factors run (PRE, POST) and group (UP, DOWN). Before neurofeedback training, the two groups did not differ significantly, but after neurofeedback training, the UP group demonstrated higher VWFA activation during the no-feedback run than the DOWN group. Mean values and error bars (depicting one standard error) are displayed on the right side of the boxplots.

Figure 6

Visual word form area activation during functional VWFA localizer runs before and after neurofeedback training. We found a significant interaction effect between the factors run (PRE, POST) and group (UP, DOWN) for the functional localizer runs. The two groups did not differ significantly in VWFA activation before or after training, but the UP group demonstrated a trend towards a decrease in activation over time while the DOWN group did not show a significant change in VWFA activation over time.