Unknown cause
Irreversible
Affects mainly memory
Hallucinations common
Hallucinations not common
Language: sometimes difficulty finding the right word
Fluctuating consciousness
Affects mainly attention
Rarely alters consciousness
Organic cause
Gradual (indefinite/insidious) onset
Acute – Not progressive
Chronic - Progressive
Language: slow, often incoherent, & inappropriate
Rapid (definite) onset
Reversible
