DISORDERS OF CONSCIOUSNESS   Consciousness: a state of awareness of the self and the environment. §         Active consciousness: when the subject focuses his attention on some internal or external event. §         Passive consciousness: when the same events attract the subject’s attention without any conscious effort on his part.       Distractibility: the pt. is diverted by almost all new stimuli and habituation to new stimuli takes longer than usual. Seen in: §         Fatigue §         Anxiety (due to anxious preoccupations) §         Severe depression §         Mania §         Schizophrenia (may be due to paranoid set or FTD) §         Organic states (may be due to paranoid set)   o        In the amnestic syndrome, the pt’s thinking and observation are dominated by rigid sets, so that perception and comprehension are affected by selective attention. o        Disorders of consciousness are associated with disorders of perception, attention, attitudes, thinking, registration and orientation. o        If a pt. is disoriented, there is a prima facie case that he has an organic state; the major exception to this rule is the chronic hospitalized schizophrenic.   Consciousness can be changed in three ways: §         Dream-like changes of consciousness §         Lowering of consciousness §         Restriction of consciousness       Dream-like changes of consciousness: §         There is some lowering of the level of consciousness which is the subjective experience of a rise in the threshold for all incoming stimuli. §         The pt. disoriented for time and place, but not for person.   §         Clinical features: ·         Visual hallucinations – usually of small animals, associated with fear or even terror; or Lilliputian hallucinations which may be associated with pleasure. ·         Disordered thinking as it is in dreams, showing excessive displacement, condensation and misuse of symbols. ·         Auditory hallucinations – commonly elementary, rarely continuous voices, organized auditory hallucinations take the form of odd disconnected words or phrases. ·         Other hallucinations of touch, pain, electric feelings, muscle sense and vestibular sensations often occur. ·         When the underlying physical illness is severe, insomnia is marked. §         ‘Occupational delirium’: when the pt. is restless and carries out the actions of his trade. §         ‘subacute delirious state’ (toxic confusional state): milder degrees of delirium, where pt. may have a general lowering of the consciousness during the day and be incoherent and confused, while at night delirium occurs with visual hallucinations and restlessness. There may also be some restriction of consciousness so that the mind is dominated by few ideas, attitudes, and hallucinations.   Lowering of consciousness (torpor): §         Pt. is apathetic, generally slowed down, unable to express himself clearly and may perseverate. §         After some weeks there is a remarkable partial recovery and the pt. is left with a mild organic defect. §         Seen in: ·         Severe infections, like typhoid and typhus. ·         Arteriosclerotic disease, following a cerebrovascular accident.       Restriction of consciousness: ·         There is some lowering of the level of consciousness, and the awareness is narrowed down to a few ideas and attitudes which dominate the pt’s mind. ·         ‘twilight state’ (Westphal): there is a - ·         a restriction of the morbidly changed consciousness ·         a break in the continuity of consciousness ·         relatively well ordered behaviour Commonest twilight state is the result of epilepsy. Simple, hallucinatory, orientated, perplexed, psychomotor, excited and expansive twilight states have been described. ·         ‘Hysterical twilight state’: the restriction of consciousness resulting from unconscious motives. Seen in severe anxiety ·         ‘Fugues’: wandering states with some loss of memory. Seen in: ·         Depression ·         Hysterical fugue: more common in subjects who have previously had a head injury with concussion. Back to Top