This article is concerned with modulus of continuity of Brownian local times. Specifically, we focus on three closely related problems: (a) Limit theorem for a Brownian modulus of continuity involving Riesz potentials, where the limit law is an intricate Gaussian mixture. (b) Central limit theorems for the projections of L 2 modulus of continuity for a one-dimensional Brownian motion. (c) Extension of the second result to a two-dimensional Brownian motion. Our proofs rely on a combination of stochastic calculus and Malliavin calculus tools, plus a thorough analysis of singular integrals.1. Introduction. Let {B t , 0 ≤ t ≤ 1} be a standard linear Brownian motion defined on some complete probability space (Ω, F, P). In the sequel, we denote by L t (x) the local time of B at a given point x ∈ R, defined for t ∈ [0, 1]. A nice combination of stochastic calculus, stochastic analysis and evaluation of singularities associated with heat kernels have recently led to a number of interesting limit theorems for quantities related to the family {L t (x); t ∈ [0, 1], x ∈ R}. Let us quote, for instance, the use of Malliavin and stochastic calculus tools in order to get suitably normalized limits for L 2 modulus of continuity (see [6,13]) or third moment in space (cf. [7]) of Brownian local time. Malliavin calculus tools have also been essential in order to generalize the notion of self-intersection local time [5,8] and to obtain central limit theorems for additive functionals [9] of fractional Brownian motion.The current article proposes to take another step into the relationships between Brownian local time and stochastic analysis. Specifically, we shall handle the following problems: