SEE:

mIS             confusion (n)

mIS             be confused,  be mixed up (v)

(qurgh < MO, qep'a' 2010):  Only used for "mental confusion" (i.e. it doesn't apply to a bunch of things mixed up on a table). 

rel             be dazed (unable to think properly) (v)

(qep'a' 2017):   in the sense of confused, unable to think properly, bewildered

(SuStel, 8/24/2017):  My guess is that mIS refers to a lack of understanding, while rel refers to an inability to concentrate.

SEE ALSO:

mer             surprise (v)
yay'            be shocked, dumbfounded (v)
Duq             be stunned (be astonished, astounded, dumbfounded, shocked) (v)

DuD             mix, stir (v)