This Why We Kiss with ~*Tongue*~

Only half of human societies lock lips

While every couple develops their own gestures of affection (you know, kissing the nape of their neck or anal sex), pretty much all of us ~*kiss on the lips*~. Okay, perhaps not all. According to Psychology Today, only roughly half of human societies show affection by locking lips. Many of those who don’t actually find the practice ‘gross’ or inappropriate. So why do those of us who do it, do it? Why do we not only press our lips against our boo’s, but throw our tongues in the mix, too?

While scientists haven’t come up with a definitive answer to this, Eric Haseltine Ph.D. shared his theory in Psychology Today. With the help of the below diagram, Haseltine tries to break things down for us.

Source: FIGURE 1 CC0 Haseltine

‘The left half of Figure 1 shows which parts of the tactile (somatosensory) brain respond with neural activation when a different part of the skin is touched,’ Haseltine explains. Adding that it’s interesting to note how stimulation of such vastly different body parts can occupy the same amount of space in the brain.

‘Notice that a single thumb occupies as much somatosensory cortex as the entire torso, meaning that tactile stimuli applied to skin on the thumb activate more brain tissue than the torso, even though torsos are much larger than thumbs.’

This is where our tongues come in

‘Notice also that lips and tongue also occupy a dis-proportionally large amount of somatosensory brain tissue.’ Our sensory brain dedicates a lot of neural tissue to certain body parts, such as our lips and tongue. This allows these body parts to pick up on and sense even small details which make contact with them.

Not only are our tongues packed with sensation, but they’re fabulous little movers and groovers. ‘When the brain devotes a lot of motor cortex to a body part, the amount of motor acuity (ability to make small, precise movements) is maximized. This means that the lips and tongue are capable of much more subtle, nuanced movements than, say, the back. This makes a lot of sense when you consider that we use our lips and tongues for speech, which requires precise motor control.’

There you have it, fam. Our tongues and fabulously complicated and packed with feel-good endings. Get smooching