  We consider a generic model of quadratic gravity coupled to a single scalar
and investigate the effects of gravitational degrees of freedom on inflationary
parameters. We find that quantum corrections arising from the massive spin-2
ghost generate significant contributions to the effective inflationary
potential and allow for a realization of the spontaneous breakdown of global
scale invariance without the need for additional scalar fields. We compute
inflationary parameters, compare the resulting predictions to well-known
inflationary models, and find that they fit well within the Planck and
BICEP/Keck collaboration's constraints on inflation.
