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Which sense does not rely on the thalamus in the same way as most other sensory systems?

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Diagram of a human brain showing a median sagittal section, highlighting the fourth ventricle and cerebellum in the hindbrain, with labeled anatomical structures including the pons, medulla oblongata, and central canal of the spinal cord. — thalamus Sagittal section of the human brain, showing structures of the cerebellum, brainstem, and cerebral ventricles.

The sense of smell (olfaction) is unique among the primary sensory systems because it does not rely on the thalamus as a primary relay station to the cerebral cortex in the same way that visual, auditory, somatosensory, and gustatory systems do.12

While most sensory signals are projected to specific relay nuclei within the thalamus before reaching the cortex, the olfactory system transmits information differently. The axons of olfactory receptor cells extend directly into the olfactory bulb, where the information is processed before being distributed to the olfactory cortex. This direct pathway to the brain distinguishes smell from other senses that require thalamic mediation to organize and relay sensory input to the primary sensory areas of the cortex.2341