From some basic research I did a while back I found that Hitler, while having exceptional verbal intelligence, would get very clammy hands and seem disorderly around new people. I figured he certainly had to deal with types of disorders that correlate highly with those who have high verbal intelligence i.e. anxiety disorders.

In 1993, the interdisciplinary team Desmond Henry, Dick Geary and Peter Tyrer published an essay in which they expressed their common view that Hitler had antisocial personality disorder as defined in ICD-10. Tyrer, a psychiatrist, was convinced that Hitler furthermore showed signs of paranoia and of histrionic personality disorder.[24]

https://en.wikipedia.org/wiki/Psychopathography_of_Adolf_Hitler#Psychopathy_/_antisocial_personality_disorder