DEPARTMENT OF NEUROBIOLOGY

Professor Ravi Allada Highlighted in Weinberg Magazine Article – While You Were Sleeping

In his relentless quest to drive innovation, Thomas Edison felt success came only to those who stayed awake.

Sleep, the inventor reasoned, was time lost — “an absurdity, a bad habit.” He eschewed a clock in his workroom and boasted of working 20 hours a day, inspiring a cult of followers — as well as his exhausted lab staff — to push themselves to similar lengths.

But even the inventor of the light bulb saw the value in a little shut-eye now and then.

When facing a complex problem in his lab, Edison was known to saunter over to an easy chair. He would hold a stainless steel ball in each hand and allow his body to relax. As he drifted off, the balls would crash to the floor. An awakening Edison would then scramble to record all of the immediate thoughts in his mind.

The man who famously bellowed that “genius is 99 percent perspiration and 1 percent inspiration” believed that sleep might actually be the key to that final drop of genius.

A century later, Weinberg College researchers agree that Edison was onto something. Sleep, they say, can be a prime time to activate memories, strengthen skills, solve problems, reset our internal clocks, and even reduce our racial and gender biases.

“The workings of our conscious mind while we are awake are but a small part of what our brains do,” says Professor of Psychology Ken Paller, who directs Northwestern’s Cognitive Neuroscience Program. “Sleep is an example of how a lot of mental activity is hidden from us, but is nevertheless critically affecting our behavior, our personality and how we store memories.”

During sleep, the brain is busily consuming energy as it cycles between different stages — from light sleep to deep sleep to the vivid, dream-inducing phase of rapid eye movement (REM) sleep. “Sleep is not a passive process,” observes Ravi Allada, chair of Weinberg College’s Department of Neurobiology, “but rather a time when the brain shifts into a different and complementary mode of activity.”

Indeed, many of us can cite an anecdote about a problem we solved while we slept — a dream that yielded a clue to a conundrum, or an answer that suddenly seemed obvious upon awakening. But how and why we do that remains rather mysterious.

“In this unresponsive, unconscious state, we can’t eat, mate or protect ourselves,” Allada muses. “And yet we spend one third of our lives in this stasis.

“Why? That question is incredibly intriguing.”

Allada, Paller and other Weinberg researchers, including Professor of Psychology Mark Beeman, are intent on solving that riddle.

Addressing disrupted sleep, Neurobiologist Ravi Allada is exploring the relationship between sleep, learning and memory by studying the molecular and cellular underpinnings of those processes.

“Ultimately, we’re asking, ‘Why do we sleep and why do we need to sleep?’” he says.

It’s a mystery Allada is unraveling with the help of fruit flies — who, like humans, sleep. “We’re using this rather simple organism to understand a complex issue,” he says.

In his efforts to understand which parts of the brain promote sleep, Allada has used a genetic tool to turn off various sets of neurons in fruit flies’ brains as they slept. As he shut off different sets of neurons, the fruit flies remained asleep — until he unplugged one particular set and the flies awoke.

“And that is the same set of neurons important for learning and memory, which suggests that sleep and learning and memory are connected,” Allada says.

This past summer, Allada and colleagues built upon their findings to explore why we wake up and go to bed at similar times each day. They studied the sleep-wake cycles of two different species — mice, who are nocturnal, and fruit flies, who active during the day. The team discovered that the cycles of both species are controlled in the same way.

“This suggests that the control of sleep is an ancient mechanism conserved across hundreds of millions of years of evolution,” Allada says.

The researchers discovered a “bicycle mechanism” that conveys important information about time to both species: when the sodium current in their neurons is high, the animals awaken; when the potassium current is high, the animals sleep.

“Like two pedals on a bicycle: when one goes up, the other goes down,” Allada says.

These findings have the potential to inspire new pharmaceuticals to address not only sleep disorders but also issues such as jet lag and shift work, thereby allowing people to reboot their internal clocks to fit their individual situations and curtail sleep deprivation. It’s a particularly critical line of inquiry, given that disrupted sleep is linked to debilitating afflictions such as Alzheimer’s and depression.

“If we can discover how sleep is accomplished, then we can design drugs and therapies specifically to improve the process of sleep or restore it to a healthy level,” Allada says.

And with that, we can capture all the potential benefits of sleep in a way that helps our minds and our bodies perform at optimal levels, perhaps even to the point that Edison might desire a nap.

To read more, visit Weinberg Magazine.

8 January 2016