  We study the Saito-Ikeda infinitesimal invariant of the ccle defined by
curves in their jacobians using rank (k+1) vector bundles and we give a
criterion for which the higher cycle class map is not trivial. When k=2, this
turns out to be strictly linked to the Petri map for vector bundles: an
explicit construction on a curve of genus g>9 shows the existence of a non
trivial element in the higher Griffiths group.
