A fast and child-friendly localizer for the identification of ITG-math based on its preference for mathematical processing
The visual number form area (here referred to as ITG-math) has gained recent attention as a neural substrate of mathematical cognition. However, research on this region has been hindered by difficulties identifying it and its precise function hence remains debated. THere we aimed to: 1) Provide an efficient and child-friendly localizer for the region and 2) explore the impact of different tasks and stimuli on its responses. In the developed localizer, participants are presented with digits and UFOs, while performing a 1-back task either on stimulus numerosity or on stimulus color. We collected two sessions of the localizer from 17 healthy adults. From the localizer data, we could identify ITG-math based on higher responses in the numerosity than the color task in 92% of the participants, whereas contrasting digits with UFOs lead to selective responses in only 32% of the participants. Accordingly, in independent data, ITG-math showed a task preference, but no stimulus preference. Multivariate analyses further revealed task encoding, and a combination of task and stimulus encoding, in the left and right ITG-math, respectively. Our work facilitates further research on ITG-math and suggests that the role of ITG-math in mathematical cognition goes beyond the visual encoding of digits.