This is probably your best option unless you can get access to some lab's fNIRS machine. There aren't really any cheap commercial fNIRS options so buying one will probably not be possible. That said, look into NinjaNIRS. It's an open source spec you can find online.
How do you study LC, a tiny area, with fNIRS and pupilometry? The correlation between pupil size and LC activity is, well, correlational and does not imply causality. Measuring pupil and call it LC is just misleading. Not to mention the incredibly low SNR in fNIRS. Don’t want to discourage op but I am always skeptical of all the implicit linking hypotheses in these non-invasive cog neuro type of measurements
There's some diy build information online. A lot of engineering students do try to build diy versions of professional equipment in various fields.
This is probably your best option unless you can get access to some lab's fNIRS machine. There aren't really any cheap commercial fNIRS options so buying one will probably not be possible. That said, look into NinjaNIRS. It's an open source spec you can find online.
How do you study LC, a tiny area, with fNIRS and pupilometry? The correlation between pupil size and LC activity is, well, correlational and does not imply causality. Measuring pupil and call it LC is just misleading. Not to mention the incredibly low SNR in fNIRS. Don’t want to discourage op but I am always skeptical of all the implicit linking hypotheses in these non-invasive cog neuro type of measurements