Our brains are mysterious, fragile, and mischievous. That’s what makes them fascinating.

 

The most exciting thing about science is that it can ferry humanity into the unknown. The scientific method, as a mode of observation piloted by humans for generations, has probed outer space, the depths of the oceans, and the inner reaches of cells, molecules, and atoms—our amazing brains at the helm. Never satisfied, the three-pound, skull-encased lump of flesh strains to know more, discover more, solve more. And the universe obliges. Unimaginably vast swaths of space lie unexplored; most of the ocean floor remains a mystery; and new insights into the functioning of cells and the nature of subatomic matter emerge on an almost daily basis.

This almost unfathomable potential for discovery and innovation always rockets to the fore of my own three-pound fleshlump when it comes time to edit our annual issue on neuroscience.

Most scientists and science enthusiasts I’ve met are intellectually inflamed by the fact that there is so much out there (and in here) that we don’t know—a passion that transcends disciplines. And is there any mystery more fascinating than the functioning of the human brain itself? After all, we carry our brains around with us every day and use them to ferret out the patterns and meanings that throng around us. Neuroscientists, even more than the rest of us, use theirs to think about thinking.

Yet, after millennia of intimate interactions with our own brains and decades of formal study of the organ, “how the brain works was and still is a complete mystery,” in the words of Albert Einstein College of Medicine neuroscientist Kamran Khodakhah, this month’s profilee.

How in the name of Ramón y Cajal can cells, amassed in tangled networks and swapping ions across their membranes to propagate waves of electrical potential, result in a thought? How does this sequence of physical events form moving pictures, symphonies, emotions, and inspiration? It truly boggles . . . well, the brain.

 
ANDRZEJ KRAUZE
 

But despite the black box around the connection between the human brain and the mind, it is clear that the flesh-and-blood organ is subject to all the ills that befall any collection of biological cells and tissues. Our brains become stuck in ruts. Our brains degenerate. Our brains deceive us.

The fragility of the human brain takes our investigations into the nuts and bolts of consciousness beyond the realm of mere curiosity. Studying brain function can help humans dodge or delay at least some of the ravages of time, environmental insult, and biological malfunction.

In this issue, two feature articles explore emerging ideas poised to reshape our concept of brain physiology. Our cover story, by Catherine Offord, relays the latest scientific findings on the impact of air pollution on neurodevelopment and cognitive function. In the second article, Ashley Yeager offers a fresh perspective on the contribution of lysosomal dysfunction to the development of Parkinson’s disease.