Fear of heights. Acrophobia. I have been trying to conquer this for decades. I admit I was able to climb up the Eiffel Tower- but that was a decade ago, and whatever new pathway my brina learned, I fear is long lost.
It is natural for humans to have a response to heights- to preclude us suffering injuries from falling. IT’s the preternatural fear that is the problem- and some 3 to 5% of us manifest that heightened anxiety.
Well, Dr. Wes Shang (East China Normal University [Shanghai], along with S Xie, W Feng, J Jia, X Cao, Z Li, Y Gu, H Shi, L Lin, YH Pan and XB Yuan, set up a series of experience with mice to further examine the phenomenon. His team found that repeated exposure to heights activate neurons in the midbrain of the mice (periaqueductal gray). IF these neurons were disabled, the fear of heights disappeared.
They also found out that when neurons from the lateral geniculate nucleus (component of the visual system) reactivated the fears. But, silencing those cells absolved the mice of their fear of heights.
It turns out another set of neurons in the midbrain structure (superior colliculus) either suppressed the fear of heights or let it run loose. (If the neurons were disabled, there was no fear of heights; non-disabled neurons involved fear of heights.)
Aa such, they discerned that the pathway between the lateral geniculate nucleus and the periaqueductal gray complex is the primary pathway for acrophobia. Moreover, an additional pathway to the superior colliculus has involvement in the response.
The researchers will now collaborate with psychologies to see if these same mechanisms apply to humans. In addition, searching for the visual cues that trigger acrophobia is part of the next steps.
