epistemology and psychology Avicenna was a pioneer of  neuropsychiatry . He first described numerous neuropsychiatric conditions, including  hallucination ,  insomnia ,  mania ,  nightmare ,  melancholia ,  dementia ,  epilepsy ,  paralysis , stroke ,  vertigo  and  tremor . [34] Avicenna was also a pioneer in  psychophysiology  and  psychosomatic medicine .