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The slicing problem can be reduced to the study of isotropic convex bodies K with $diam\left(K\right)\le c\surd n{L}_K$, where $L_K$ is the isotropic constant. We study the ψ₂-behaviour of linear functionals on this class of bodies. It is proved that ${\left|\right|⟨·,\theta ⟩\left|\right|}_{\psi ₂}\le C{L}_K$ for all θ in a subset U of $S^{n-1}$ with measure σ(U) ≥ 1 - exp(-c√n). However, there exist isotropic convex bodies K with uniformly bounded geometric distance from the Euclidean ball, such that $ma{x}_{\theta \in S^{n-1}}{\left|\right|⟨·,\theta ⟩\left|\right|}_{\psi ₂}\ge c∜n{L}_K$. In a different direction, we show that good average ψ₂-behaviour of linear functionals on an isotropic...