When people see an image of a person they recognize – the famous tennis player Roger Federer or actress Halle Berry, for instance – particular cells light up in the brain. Now, researchers reporting in Current Biology on September 21 have found that those cells light up even when a person sees a familiar face or object but fails to notice it. The only difference in that case is that the neural activity is weaker and delayed in comparison to what happens when an observer consciously registers and can recall having seen a particular image.
The findings offer new insight into the nature of conscious perception, the researchers say.
“Our study finds that a ‘Roger Federer cell’ can also become active when its owner fails to notice the image of Roger Federer rapidly flickering by in a stream of other images,” says Florian Mormann of University of Bonn Medical Center in Germany. “Thus, we find that there is highly abstract information present in neuronal activity that is inaccessible to conscious experience.”
The researchers made the discovery by recording the activity of 2,735 individual neurons in 21 neurosurgical patients implanted with brain electrodes for epilepsy monitoring. They took advantage of a phenomenon known as attentional blink in which people who attend to two familiar images in quick succession will often fail to notice the second. The experimental setup allowed the researchers to directly compare the neural response to seen and unseen presentations of the very same image.
As expected, study participants often failed to notice the presence of a second target image, especially when it was presented soon after a first target image. The researchers found that the corresponding neurons fired either way. However, there was an observable difference in the strength and timing of that neural response.
“Studying the activity of individual neurons in awake, behaving humans was key to picking up weak but informative signals from individual neurons during nonconscious perception, particularly in regions further down the processing stream, which are impossible to measure with conventional tools,” Mormann says. “We were quite surprised to see that timing of neuronal responses is indicative of whether participants report having seen the image or not.”
The findings weigh in on theoretical debates about the nature of human consciousness, the researchers say. For instance, it hasn’t been clear whether consciousness is an all-or-nothing phenomenon or a matter of degrees. The researchers say the observation that neuronal firing occurs in both cases, but differently, argues in favor of consciousness as a more nuanced, graded phenomenon.
The researchers say they’d now like to explore how the activity of individual neurons in one part of the brain is related to activity in other brain areas and how those connections relate to conscious awareness.
.
© Edublox
Fundamental solutions to reading challenges –
“It’s been six months … and already she is one of the top performers in her class”
I was told that my daughter would never make it in a mainstream school and that she had to be transferred to a remedial school... She is getting 6's and 7's and she is in mainstream school. Continue Reading
Zan’s Mom, South Africa Edublox Online Tutor December 21, 2013
Dyslexia case study presented at Kennesaw State University
The Edublox Program has given hope to a child who knew he was different, tried to fit in with his peers, and experienced failures in any aspects of school. His newly found confidence has allowed him to raise his hand in a classroom, dared him to try written material presented to him, and opened a world of "I can" instead of "I can't" on new material. Continue Reading
Carole Derrick, Primary Grades Teacher Edublox Online Tutor June 24, 2015
“His English has jumped from 42% to 58%; he is writing compositions that bring tears to my eyes”
Preneil was diagnosed with dyslexia at the age of thirteen. His mother shares her son's progress after joining Edublox. Read the full story. Continue Reading
Devigi Pillay, South Africa Edublox Online Tutor January 26, 2016
“My dyslexic son doesn’t seem to be dyslexic anymore”
I never thought I would be writing this statement, but my dyslexic son doesn't seem to be dyslexic anymore! The symptoms have all disappeared. After all I've read on the subject of learning difficulties, this was not supposed to happen! Continue Reading
Laura Trudel, Canada Edublox Online Tutor November 12, 2016
“A program that truly stands up to [its] promises and offers hope to those who struggle”
We just received his first semester report card and I am so excited to say that he received an “A” in both English and Math. Continue Reading
Teresa M., California, US Edublox Online Tutor November 28, 2016
“He is devouring books at a rapid rate”
Six months ago reading a book was tortuous for him because even if he read it his reading was so faltering and full of mistakes that he couldn’t comprehend the text. Continue Reading
Abi Stinson, UK Edublox Online Tutor November 29, 2016
“After six weeks the improvements were very obvious”
The most noticeable improvement came with Math, because we were struggling trying to do his math at grade level (3rd grade), but then around six weeks into Edublox he could do his math at grade level (with the exception of telling time on a face clock and counting money). Continue Reading
Cindy B., Michigan, US Edublox Online Tutor December 1, 2016
“His reading age went up by 2 years in less than 6 months”
His spelling age improved as well and he also did really well in the end of year exams with his best results in most subjects. Continue Reading
Jenny & Greg, UK Edublox Online Tutor December 6, 2016
“In the first 9 weeks of school they have increased over 2 1/2 years”
Phonics just did not work. Last year they did not improve in their reading level all year. We started Edublox in June and already in the first 9 weeks of school they have increased over 2 1/2 years.... Their spelling has greatly improved and learning new words has become a game, not the dreaded chore it once was. Continue Reading
Nita Brist, Washington State, US Edublox Online Tutor December 11, 2016
“I feel as if part of my daughter’s mind was trapped, and Edublox set her free”
She is now almost an intuitive speller. Really, it's a miracle. Six months ago, her spelling tested at a Kindergarten level, and is now at a 6th grade level. This is just still so amazing to all of us who have struggled with her. Continue Reading
The Adams household in New Mexico Edublox Online Tutor December 15, 2016