can i straighten my hair?

so tomorrow i have an appointment with my new neurologist and my mom told me not to put any product in my hair because apparently they're going to put this thing on my head that reads my brain waves or something and hair products could react with the device and cause it to fail. but can i straighten my hair, like i normally do? i mean i'm not putting any product in my hair so i guess i would be fine but i want second opinions. help?