Fewer of both actually, but both are critical for touch to work. it gets a bit more complex at the synapses where it essentially becomes ion flows between transmitting and receiving axons/dendrites, but both photonic movement and electron exchange are critical.
As these are electrons and ions, there is no such notion within context as "parent atoms". Also, dark matter does not interact with normal matter and so is of no consequence to any discussion of reading, via touch or vision.