The electrocalciothermic reduction mechanism may be represented by the following sequence of reactions, where "M" represents a metal to be reduced (typically titanium).
When this reaction takes place on its own, it is referred to as the "calciothermic reduction" (or, more generally, an example of metallothermic reduction).  For example, if the cathode was primarily made from TiO then calciothermic reduction would appear as:
Whilst the cathode reaction can be written as above it is in fact a gradual removal of oxygen from the oxide. For example, it has been shown that TiO does not simply reduce to Ti. It, in fact, reduces through the lower oxides (TiO, TiO, TiO etc.) to Ti.
The calcium oxide produced is then electrolyzed:
: (2a)   
: (2b)   
and
: (2c)   
Reaction (2b) describes the production of Ca metal from Ca ions within the salt, at the cathode. The Ca would then proceed to reduce the cathode.
The net result of reactions (1) and (2) is simply the reduction of the oxide into metal plus oxygen: