Impairment of consciousness and attention (ranging from clouding to coma; reduced ability to direct, focus, sustain and shift attention)

Global disturbance of cognition (perceptual distortions, illusions and hallucinations – most often visual; impairment of abstract thinking and comprehension, with or without transient delusions, but typically with some degree of incoherence; impairment of immediate recall and of recent memory, but with relatively intact remote memory; disorientation for time as well as in more severe cases for place and person)

Psychomotor disturbances (hypo- or hyperactivity and unpredictable shifts from one to the other; increased reaction time; increased or decreased flow of speech; enhanced startle reaction)

Disturbance of the sleep/wake cycle (insomnia or, in more severe cases, total sleep loss or reversal of the sleep/wake cycle; daytime drowsiness; nocturnal worsening of symptoms; disturbing dreams or nightmares, which may continue as hallucinations after awakening)

Emotional disturbances, for example, depression, anxiety or fear, irritability, euphoria, apathy or wandering, perplexity