brain, memory
脳 centers on the brain as the organ of thought and memory. The memory sense is a natural extension of the brain's function.
脳 is the modern simplified form of 腦. The older form combines ⺼ (flesh/body part) with a phonetic component that also suggests the idea of the brain. The modern simplification replaces the right side with 凶, which is not historically related to the original component.
The left side ⺼ is flesh, and the bottom 凶 looks like a container with something inside. Picture the skull as a container holding the fleshy brain.
For ノウ, imagine a brain that knows everything: know -> ノウ. The brain stores all your knowledge and memories.
brain
brainwashing
head; leader; top
brains; brain tissue
head; brains
computer
brain waves
cranial nerves; cerebral nerves
stroke; cerebral haemorrhage; cerebral hemorrhage
one's mind
brain death
brain tumor; brain tumour
cerebrum
top of the head; crown of the head
right brain
left brain
brain inflammation; encephalitis; cerebritis
brain surgery
encephalopathy
cerebellum