Symptom or sign

Comment

Early onset

Usually before the age of 5

Hyperactive

Especially when self-employed, fidgeting, and restless

Lack of concentration

Especially on cognitive tasks over time

Impulsive

Acting without considering consequences

Social isolation

Rejected by peers due to impulsivity, aggression and inability to await turn

Dyslexia

Found in up to 30%

Attention problems

Easily distracted from tasks

Aggression

Caused by frustration at work and play

Low galvanic skin response

Low arousal

Fast habituation

To sensory inputs

EEG changes

Common.