They are represented by light blue in diagrams. Association AreasĪssociation areas give meaning to sensations. Primary Visual Cortex Note the crossing of optic nerves at optic chiasm and continuation as optic tracts. The amount of cortex devoted to a particular body part is directly proportional to that parts sensitivity. It’s easy to remember the postcentral gyrus is posterior to the precentral gyrus because it’s in the name: postcentral. The precentral gyrus is all motor while the postcentral gyrus is all sensory. The primary somatosensory cortex sends axons from posterior to anterior. The olfactory cortex is also called the Rhinencephalon, or “nose brain.” This is the most primitive part of the cerebrum and connects directly to the limbic system (emotional system), which is why smells often directly trigger emotions as well as our deepest memories. The olfactory cortex is located on the medial aspect of the temporal lobe, in the uncus (aka piriform lobe). This cortex is where you get sensation of smell, before you’ve figure out what the smell is. On top of the cribriform are the nasal foramina and they hit the olfactory bulb which then run toward the primary olfactory cortex through the olfactory tract. Something that isn’t shown is the vestibular cortex which is located in the insula, just below the temporal and frontal lobes. These are represented with dark blue in the diagrams and include somatosensory, visual, auditory, vestibular, taste, smell, visceral sensations. 2 special motor cortices (Frontal Eye Field, Broca’s area) Primary Sensory Cortexįor each of the major senses, there is an area called the primary sensory cortex.Primary Motor Cortex – sends signals to generate movements.Motor areas – allow you to act upon a sensation
Multimodal Association Areas – make associations between different types of stimuli.Association areas – give meaning to/make associations with a sensation.Primary Sensory Cortex – makes you aware of a sensation.