There’s an epidemic in the US and other Western nations destroying the lives of young adults and teens in particular, although all ages are susceptible. The debilitating disease targets the brain, peeling away cells and disrupting biological systems, leaving some victims bedridden for weeks. Many have heard of this, but few know how it works.

The disease starts with the eyes. The light hits the retinas, whose cells compile an image based on the light, firing chemical and electrical activity down their axons, through the optic tracts to the visual cortex in the back of the brain. From here, this cascade of neural signaling fans out over the top and bottom portions of the brain, propagating the original signal, sending this disease-ridden image throughout the brain like a virus.

Next, it affects the ears. Sound waves bounce through the ear canal, moving and shifting cellular hairs that trigger more chemical electrical reactions, sending the harmful sound waves through the cochlear nerve up to a small bump in the brain located roughly above the ear. Much like the visual cortex, the auditory cortex further elaborates on the meaning of its stimulus and then sends it along to other regions of the brain.

Deep within the frontal lobes, the largest sections of the brain, and the temporal lobes, the stimuli that attacked the eyes and the ears join in another form, disrupting the natural balance and functioning of norepinephrine, dopamine and serotonin within the brain, three chemicals that modulate things like wake-sleep cycles, appetite, motivation, reward values, memory and physical reaction to danger.

The disease that we’re talking about is, of course, depression and this is how it happens. Words, embodied by soundwaves, and visual scenes, reduced to light, are the primary mechanisms of infection. Once they permeate the brain, they can travel rapidly and unimpeded, infecting further areas of the cortex and structures deep within the cerebrum.The constant barrage of the same scenes, the same words, inducing the same processing and negative emotions begin to take a toll on the body, literally and physically stripping away at motivation, even the motivation to live (if that can be quantified).