How is olfactory information processed in the brain?

Olfactory information processing in the brain is primarily routed through the olfactory bulb, which is responsible for receiving input from olfactory sensory neurons in the nasal cavity. From the olfactory bulb, this information is then transmitted directly to the limbic system, which plays a critical role in emotions, memories, and the overall emotional response to smells. This direct pathway is significant because it allows odors to evoke strong emotional responses and memories, often before one consciously recognizes the scent.

The olfactory system is unique among the sensory systems because it bypasses the thalamus, the typical relay station for sensory information, and instead connects directly to areas of the brain that are closely linked to emotional processing and memory. This is why the correct answer emphasizes the direct pathway from the olfactory bulb to the limbic system. Other pathways mentioned in the options do not accurately reflect the established route for olfactory information.