Can we actually read words and phrases and solve multi-step mathematical problems without our having consciously been aware of them? A team in the Psychology Department at the Hebrew University has conducted a series of experiments that give a positive answer: people can read and do math non-consciously.
The results constitute a challenge to existing theories of unconscious processes, that maintain that reading and solving math problems -- two prime examples of complex, rule-based operations – require consciousness.
The conclusions of the Hebrew University team were published this week in PNAS (Proceedings of the National Academy of Sciences) in the US. The research team, headed by Dr. Ran Hassin, included graduate students Asael Sklar, Ariel Goldstein, Nir Levy and Roi Mandel, as well as Dr. Anat Maril.
To present sentences and equations unconsciously, the researchers used a cutting-edge technique called Continuous Flash Suppression (CFS). In CFS, one eye is exposed to a series of rapidly changing images, while the other is simultaneously exposed to a constant image. The rapid changes in the one eye dominate consciousness, so that the image presented to the other eye is not experienced consciously. Using this technique, more than 270 students at the Hebrew University were exposed to sentences and arithmetic problems.
In one set of experiments using this technique, participants were asked to pronounce numbers that appeared on a computer's screen. These numbers were preceded with unconscious arithmetic equations. The results of the experiments showed that participants could more quickly pronounce the conscious number if it had been the result of the unconscious equation. For example, when 9-5-1 was shown non-consciously, the participants were faster in pronouncing 3 than 4, even though they did not consciously see the equation.
In another set of experiments reported in the PNAS paper, participants were non-consciously exposed to a number of short verbal expressions that remained on screen until participants could say that they saw them. (In the meantime, the other eye was exposed to the rapidly flashing images). The results showed that negative verbal expressions (e.g., human trafficking) or unusual phrases (e.g., the bench ate a zebra) became conscious to the viewers before more positive expressions (e.g., ironed shirt and more usual phrases (e.g., the lion ate a zebra), indicating a definite "pickup" by the unconscious of something negative and out of the ordinary.
"These results show that the humans can perform complex, rule-based operations unconsciously, contrary to existing models of consciousness and the unconscious," say the researchers.
"Therefore," said Dr. Hassin, "current theories of the unconscious processes and human consciousness need to be revised. These revisions would bring us closer to solving one of the biggest scientific mysteries of the 21st century: What are the functions of human consciousness."
The Hebrew University of Jerusalem: http://www.huji.ac.il
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
Results of largest ever genetics study of a single population could also help refine dates for major events during human evolution Humans are evolving more rapidly than previously thought, according to the largest ever genetics study of a single population.
Latest genetic tests reveal another break in the male line, potentially undermining the legitimacy of the entire House of Plantagenet When scientists revealed last year that an adulterous affair had apparently broken the male line in Richard III’s family tree, they vowed to investigate further.
By 2016, Icelandic genetics company deCODE will have data on half the country's population. Releasing the data will be controversial, but could save lives
A clinical trial has shown that the drug aducanumab slows cognitive decline in people with Alzheimer's and reduces the amount of amyloid plaque in their brain
A leading researcher issues a call for pills that deliver a full course of treatment in one swallow.One of the world’s preëminent biomedical researchers is calling for a concerted effort by scientists to develop pills that would stay in the stomach or gut for weeks or months once swallowed, delivering one or more drugs continuously or over set intervals.
Two genes responsible for building up drug-resistance can easily be shared between a family of bacteria
When malaria parasites infect blood, they manufacture odor molecules that smell sweet to mosquitoes, scientists report. So how do these odors get from the bloodstream to the insects?
Researchers are developing new method of wireless deep brain stimulation.
Zoos belonging to World Association of Zoos and Aquariums filmed allowing shocking mistreatment of elephants, dolphins, lions, bears, penguins and whales
Owners of Highland Wildlife Park hope Victoria, 18, will get chummy with male Arktos during her stay in the Cairngorms