In the setting of abstract Markov maps, we prove results concerning the convergence of renormalized Birkhoff sums to normal laws or stable laws. They apply to one-dimensional maps with a neutral fixed point at 0 of the form x+x(1+alpha), for alphais an element of(0, 1). In particular, for alpha>1/2, we show that the Birkhoff sums of a Holder observable f converge to a normal law or a stable law, depending on whether f(0)=0 or f(0)not equal0. The proof uses spectral techniques introduced by Sarig, and Wiener's Lemma in non-commutative Banach algebras.