‘Morning people’ and ‘night owls’ show different brain function2 February, 2012 at 08:00 | Posted in Body & Mind, Science | Leave a comment
Tags: Body & Mind, Science
By Quinn Phillips
Edmonton – Are you an “early bird” or a “night owl?”Scientists at the University of Alberta have found there are significant differences in the way our brains function depending on whether we’re early risers or night owls.
Neuroscientists in the Faculty of Physical Education and Recreation looked at two groups of people: “morning people,” those who wake up early and feel most productive in the morning, and those who were identified as “evening people,” who typically felt livelier at night.
Eighteen study participants were placed in two groups (nine morning people and nine evening people) after completing a standardized questionnaire about their habits. The participants were tested four times throughout the day: at 9 a.m., then in the afternoon at 1, 5 and 9 p.m., using three different techniques.
“We measured how much muscle force the two different participant groups could each generate during maximum contractions [and] we applied electrical stimulation to a nerve in the back of the knee to assess pathways through the spinal cord,” said graduate student Olle Lagerquist, who came up with the original idea for the experiments.
“We also used trans-cranial magnetic stimulation-a magnet that we hold over the cortex-to stimulate brain cells to send a signal to different muscles.”
The research team, made up of Lagerquist and fellow student Alex Tamm, technician Alejandro Ley and neuroscientist Dave Collins, made three major discoveries, the biggest of which was the difference in brain activity between the two groups.
“In morning people their cortical excitability actually decreased throughout the day. It was highest in the morning and lowest in the evening,” said Tamm. “It was the opposite for evening people; their brain activity was highest at 9 p.m.”