  We try to clarify what are the genuine quantal effects that are associated
with generalized Brownian Motion (BM). All the quantal effects that are
associated with the Zwanzig-Feynman-Vernon-Caldeira-Leggett model are
(formally) a solution of the classical Langevin equation. Non-stochastic,
genuine quantum mechanical effects, are found for a model that takes into
account either the disordered or the chaotic nature of some environment.
