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We study the spectrum P_\zeta and bispectrum B_\zeta of the primordialcurvature perturbation \zeta when the latter is generated by scalar and vectorfield perturbations. The tree-level and one-loop contributions from vectorfield perturbations are worked out considering the possibility that theone-loop contributions may be dominant over the tree level terms (both (either)in P_\zeta and (or) in B_\zeta) and viceversa. The level of non-gaussianity inthe bispectrum, f_{NL}, is calculated and related to the level of statisticalanisotropy in the power spectrum, g_\zeta. For very small amounts ofstatistical anisotropy in the power spectrum, the level of non-gaussianity maybe very high, in some cases exceeding the current observational limit.

Non-gaussianity at tree and one-loop levels from vector field perturbations