Allan Hobson has developed a brain dreaming model in which he uses some terminology of computer technology. Hobson’s dreaming model consists of three major columns which highlight the brain’s different activities:

Activation (A),

The Input-Output Gating (I) and

Modulation (M).

The similarities re the states of consciousness are

Activation (A):

• the narrative coherence in dreams,               
• the experienced personal elements, and 
• the emotional salience.
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The differences re the states of consciousness are

Input-Output Gating and Modulation 

• Hallucinations                       
• Delusions                             
• Bizarreness                  
• Emotions, and
• Amnesia.

In waking attention, sensation, perception, memory, orientation, logic are ‘switched on’, whereas in dreaming all these functions, with the exception of a decreased memory function, are ‘switched off’.

Based on the three dimensional model Activation (A), the Input-Output Gating (I) and Modulation (M) Prof. Hobson, explains further in which physiological states how the brain activity works:

• Wakening (full Activation and Modulation, but different levels of Input-Output Gating),
• NREM sleep (zero Input-Output Gating, different levels of Activation and Modulation),
• REM sleep (zero Input-Output Gating, low levels of Modulation, but highest levels of Activation).

The disease model of narcoplepsy (from full Activation, Modulation and Input-Output Gating, to zero Modulation, Input-Output Gating, but still full Activation) and examples of lucid dreaming further visualized this model.

Prof. Hobson also analyzed the hallucinatory and bizarre aspects a personal dream, he had immediately noted after awakening in the night: Hobson riding a bicycle with a 6 ft tree trimmer in London’s heavy traffic.