What structure acts as a relay station for sensory information, except for olfactory signals?

The thalamus is indeed the structure that acts as a relay station for sensory information, making it the correct answer. It is a vital part of the brain that processes and transmits sensory information to appropriate areas of the cerebral cortex. This includes signals related to vision, hearing, touch, and taste, but notably excludes olfactory signals, which are routed directly to the olfactory bulb and then to the regions of the brain involved in smell.

The other structures mentioned have different primary functions. The hypothalamus is crucial for regulating various autonomic functions including hunger, thirst, temperature control, and even circadian rhythms; it is more involved with homeostasis than acting as a relay for sensory input. The cerebellum plays a key role in motor control, coordination, and balance rather than processing sensory information. The corpus callosum connects the left and right hemispheres of the brain and facilitates interhemispheric communication, but it does not serve as a relay for sensory information. Hence, the thalamus is uniquely positioned in its role among the listed options.