Note 16: 
    In the present essay, as often in the literature,  the term frontal lobe means the prefrontal cortex only 
(Fig. 3). 
    Since frontal functions depend specifically  on certain parts of the basal ganglia and of the thalamus, these
subcortical components are included under  the
term the (pre)frontal system. 
    So, when we speak of  functions of the frontal lobe, it should be kept in mind 
that we may really be speaking of (pre)frontal system  functions.