Thanks for posting your query at DoctorSpring.com
I can understand your concern.
This seems to be a fungal infection called pityriasis versicolor. This is definitely not related to nervous system in any way.
It happens in conditions of heat and humidity. Its a benign infection and the colour comes back after eight weeks.
You will need to apply nizoral lotion , take equal quantity of water to be applied on the back and front below neck for 15 mins before bath for two weeks and then stop it.
This will help eliminate the fungus.
Hope this helps.