'Subconscious' spells are their own category, meaning they all work without the caster being conscious.
There is that brief note about Awaken spells in Spell Law, but further on there is actually a better description of the class and a code for it in the Spell Description Key (section 11.3, p. 35 of the Red Band edition RM2 Spell Law).
'S -- Subconscious spell; a spell that is triggered by the subconscious; the caster must (normally) be concentrating or in a trance or unconscious or stunned before the spell will work. Some do not require the conscious casting of the caster.'
So, any spell marked with an 'S' is of this type.