Sunday, March 18 , 2018, 1:11 am | Fair 45º


UCSB Study Reveals Overthinking Can Be Detrimental to Human Performance

Trying to explain riding a bike is difficult because it is an implicit memory. The body knows what to do, but thinking about the process can often interfere. So why is it that under certain circumstances paying full attention and trying hard can actually impede performance? A new UC Santa Barbara study, published Tuesday in the Journal of Neuroscience, reveals part of the answer.

Taraz Lee, a postdoctoral scholar working in UCSB's Action Lab and the study's lead author.

There are two kinds of memory: implicit, a form of long-term memory not requiring conscious thought and expressed by means other than words; and explicit, another kind of long-term memory formed consciously that can be described in words. Scientists consider these distinct areas of function both behaviorally and in the brain.

Long-term memory is supported by various regions in the prefrontal cortex, the newest part of the brain in terms of evolution and the part of the brain responsible for planning, executive function, and working memory.

"A lot of people think the reason we're human is because we have the most advanced prefrontal cortex," said the study's lead author, Taraz Lee, a postdoctoral scholar working in UCSB's Action Lab.

Two previous brain studies have shown that taxing explicit memory resources improved recognition memory without awareness. The results suggest that implicit perceptual memory can aid performance on recognition tests. So Lee and his colleagues decided to test whether the effects of the attentional control processes associated with explicit memory could directly interfere with implicit memory.

Lee's study used continuous theta-burst transcranial magnetic stimulation (TMS) to temporarily disrupt the function of two different parts of the prefrontal cortex, the dorsolateral and ventrolateral. The dorsal and ventral regions are close to each other but have slightly different functions. Disrupting function in two distinct areas provided a direct causal test of whether explicit memory processing exerts control over sensory resources –– in this case, visual information processing –– and in doing so indirectly harms implicit memory processes.

Participants were shown a series of kaleidoscopic images for about a minute, then had a one-minute break before being given memory tests containing two different kaleidoscopic images. They were then asked to distinguish images they had seen previously from the new ones.

"After they gave us that answer, we asked whether they remembered a lot of rich details, whether they had a vague impression, or whether they were blindly guessing," Lee explained. "And the participants only did better when they said they were guessing."

The results of disrupting the function of the dorsolateral prefrontal cortex shed light on why paying attention can be a distraction and affect performance outcomes.

"If we ramped down activity in the dorsolateral prefrontal cortex, people remembered the images better," Lee said.

When the researchers disrupted the ventral area of the prefrontal cortex, participants' memory was just slightly worse.

"They would shift from saying that they could remember a lot of rich details about the image to being vaguely familiar with the images," Lee said. "It didn't actually make them better at the task."

Lee's fascination with the effect of attentional processes on memory stems from his extensive sports background. As he pointed out, there are always examples of professional golfers who have the lead on the 18th hole, but when it comes down to one easy shot, they fall apart.

"That should be the time when it all comes out the best, but you just can't think about that sort of thing," he said. "It just doesn't help you."

His continuing studies at UCSB's Action Lab will focus on dissecting the process of choking under pressure. Lee's work will use brain scans to examine why people who are highly incentivized to do well often succumb to pressure and how the prefrontal cortex and these attentional processes interfere with performance.

"I think most researchers who look at prefrontal cortex function are trying to figure out what it does to help you and how that explains how the brain works and how we act," Lee said. "I look at it at the opposite. If we can figure out the ways in which activity in this part of the brain hurts you, then this also informs how your brain works and can give us some clues to what's actually going on."

Co-authors of the just-published study are Robert Blumenfeld of the Helen Wills Neuroscience Institute and Mark D'Esposito of the Department of Psychology, both at UC Berkeley. This work was supported by a National Institutes of Health grant.

  • Ask
  • Vote
  • Investigate
  • Answer

Noozhawk Asks: What’s Your Question?

Welcome to Noozhawk Asks, a new feature in which you ask the questions, you help decide what Noozhawk investigates, and you work with us to find the answers.

Here’s how it works: You share your questions with us in the nearby box. In some cases, we may work with you to find the answers. In others, we may ask you to vote on your top choices to help us narrow the scope. And we’ll be regularly asking you for your feedback on a specific issue or topic.

We also expect to work together with the reader who asked the winning questions to find the answer together. Noozhawk’s objective is to come at questions from a place of curiosity and openness, and we believe a transparent collaboration is the key to achieve it.

The results of our investigation will be published here in this Noozhawk Asks section. Once or twice a month, we plan to do a review of what was asked and answered.

Thanks for asking!

Click here to get started >

Support Noozhawk Today

You are an important ally in our mission to deliver clear, objective, high-quality professional news reporting for Santa Barbara, Goleta and the rest of Santa Barbara County. Join the Hawks Club today to help keep Noozhawk soaring.

We offer four membership levels: $5 a month, $10 a month, $25 a month or $1 a week. Payments can be made through PayPal below, or click here for information on recurring credit-card payments.

Thank you for your vital support.

Reader Comments

Noozhawk is no longer accepting reader comments on our articles. Click here for the announcement. Readers are instead invited to submit letters to the editor by emailing them to [email protected]. Please provide your full name and community, as well as contact information for verification purposes only.

Daily Noozhawk

Subscribe to Noozhawk's A.M. Report, our free e-Bulletin sent out every day at 4:15 a.m. with Noozhawk's top stories, hand-picked by the editors.

Sign Up Now >