  UV/optical variability in quasars is a well-observed phenomenon, yet its
primeval origins remain unclear. This study investigates whether the accretion
disk turbulence, which is responsible for UV/optical variability, is influenced
by the close environment of the accretion by analyzing the correlation between
variability and infrared emission for two luminous SDSS quasar samples. The
first sample includes light curves from SDSS, Pan-STARRS, and ZTF $g$ band
photometry, while the second sample utilizes SDSS Stripe 82 $g$ band light
curves. We explore the correlation between the $g$ band excess variance
($\sigma_{rms}$) and the wavelength-dependent infrared covering factor ($L_{\rm
IR}(\lambda)/L_{\rm bol}$), controlling for the effects of redshift,
luminosity, and black hole mass. An anti-correlation between two variables is
observed in both samples, which is strongest at wavelengths of 2-3$\mu$m but
gradually weakens towards longer wavelength. This suggests the equatorial dusty
torus (which dominates near-infrared emission) plays a significant role in
influencing the UV/optical variability, while the cooler polar dust (which
contributes significantly to mid-infrared emission) does not. The findings
indicate that quasar variability may be connected to the physical conditions
within the dusty torus which feeds the accretion, and support the notion that
the close environment of the accretion plays an important role in regulating
the accretion disk turbulence.
