Recent research aims to explain why the aging brain is more distractible.
Despite my better intentions, many evenings find me lounging on the couch in our basement TV room, focused intently on the ebb and flow of some sporting event. When the game ends, my job is to turn off and unplug the space heater before spreading a piece of plastic sheeting over the couch — thus dissuading our cat Molly from using my comfy divan as her litter box.
Twice in the past couple of weeks, however, I’ve completely forgotten to cover the couch. And I once even left the heater running, which makes for a cozy environment until the electric bill arrives. On one occasion, I was also handling laundry duties, so I suppose I can blame my distraction on the rigors of multitasking. I have no idea what happened in the other case, but recent research may provide a clue.
A University of Southern California study suggests that, as we grow older, a particular part of our brains tends to malfunction under stressful conditions, making us more prone to distraction. At the center of this quandary is the locus coeruleus, a tiny region of the brainstem whose job it is to trigger the release of norepinephrine, an attention-enhancing hormone, when we find ourselves in tense situations. When this process is functioning at peak efficiency, excitable neurons become more excited while tranquil neurons chill out, essentially placing the brain on red alert — intensely focused on the task at hand.
Researchers compared the distractibility of 28 young people with that of 24 seniors by measuring brain activity while asking them to identify various images. They amped up the pressure by informing the participants that they might receive an electric shock at the conclusion of the test. The results showed that the older brains never shifted into high gear and were thus less focused than the younger group.
“Trying hard to complete a task increases emotional arousal, so when younger adults try hard, this should increase their ability to ignore distracting information,” senior study author Mara Mather, PhD, explained in a statement. “But for older adults, trying hard may make both what they are trying to focus on and other information stand out more.”
It occurs to me that this may explain why my high school industrial arts teacher stood ready to deliver a few volts into my fingers if I screwed up on an electrical circuit test. I had always assumed he was simply sadistic, but he was probably more focused on activating my locus coeruleus. It also sheds some light on my recent late-night distractibility. It’s entirely possible that the excitement of a closely contested basketball game could suppress what’s left of my brain’s attention-enhancing neurons in the same way as the geezers experienced in the USC study.
If there’s an upside to this, it’s probably the fact that Molly is even more distractible than I am. That couch remains unsoiled.