Navigation Links
New insight into people who 'see' colors in letters and numbers

People with a form of synesthesia in which they see colors when viewing letters and numbers really do see colors, researchers, led by Edward M. Hubbard of the University of California San Diego, have found. What's more, functional magnetic resonance imaging (fMRI) of their brains reveals that they show activation of color-perception areas.

The researchers said their findings lend support to the hypothesis that the condition is due to cross-activation between adjacent brain areas involved in perceiving shapes and colors. Some synesthetes report seeing colors when listening to music, or feeling tactile shapes while tasting food. This cross-activation might develop, they theorize, by a failure of the "pruning" of neural connections between the areas in the developing brain.

The rare condition called synesthesia--in which people's sensory perceptual circuitry seems to be miswired--was long dismissed as an oddity not worthy of scientific study. Now, however, researchers such as Hubbard and his colleagues are using the condition to gain insights into the neural basis of perception.

In their experiments with synesthetes who report seeing colors when they view numbers or letters, the researchers first sought to determine whether synesthetes really see the colors.

In one such experiment, they presented six synesthetes with patterns of black letters or numbers--known as "graphemes"--on a white background. They chose those graphemes that the synesthetes reported elicited specific colors. They designed the experiment so that if the synesthetes really were seeing the colors, that color perception would help them distinguish shapes such as triangles or squares formed by the graphemes. In another experiment, the researchers found that synesthetic color helped the synesthetes pick out specific numbers or letters in a crowded display.

The researchers found that the synesthetic colors really did help the synesthetes distinguish the shapes or gra phemes, compared to normal control subjects who were tested on the same patterns. However, the experiments with both the synesthetes and the controls also revealed that the synesthetic colors were not as effective as real colors in such tasks.

In fMRI scans, the researchers found that the synesthetes showed greater activation in a color-perception region of the cortex when viewing graphemes, compared to normal control subjects. The researchers found that the strength of this activation influences the strength of the synesthetic colors. In fMRI, harmless radio waves and magnetic fields are used to map regions of higher blood flow in the brain, which reflects higher activity in those regions.

Importantly, the researchers found evidence suggesting that synesthetes may be quite different from one another, which the researchers said "has profound implications for the studies of synesthesia that group together data from multiple synesthetes and treat them as if they all come from a homogeneous population.

"The use of single case studies in synesthesia is also of concern because the results obtained with one synesthete may not generalize to other synesthetes.

The researchers concluded that "Our results suggest that synesthetic colors lead to improved behavioral performance in a manner similar to real colors. Because this study uses both psychophysical and neuroimaging measures in the same subjects in the study of synesthesia, we are able to examine specific aspects of the synesthetic experience that previous studies have not been able to address."

Edward M. Hubbard, A. Cyrus Arman, Vilayanur S. Ramachandran, and Geoffrey M. Boynton: "Individual Differences among Grapheme-Color Synesthetes: Brain-Behavior Correlations"


Source:Cell Press

Related biology news :

1. Alaskan puzzles, monitoring provide insight about North Pacific salmon runs
2. New insight into regulation of blood stem cells
3. New insight into autoimmune disease: Bacterial infections promote recognition of self-glycolipids
4. New insights into how Huntingtons disease attacks the brain
5. Gambling monkeys give insight into neural machinery of risk
6. Structures of marine toxins provide insight into their effectiveness as cancer drugs
7. Flies on speed offer insight into the roles of dopamine in sleep and arousal
8. Grasshopper love songs give insight into sensory tuning
9. Studies on human genome variation provide insight into disease
10. Study provides insight into cellular defenses against genetic mutation
11. New insights into the software of life
Post Your Comments:

(Date:5/9/2016)... 9, 2016 Elevay is currently ... expanding freedom for high net worth professionals seeking travel ... globally connected world, there is still no substitute for ... duplicate sealing your deal with a firm handshake. This ... taking advantage of citizenship via investment programs like those ...
(Date:4/26/2016)... and LONDON , ... Finacle, part of EdgeVerve Systems, a product subsidiary ... Onegini today announced a partnership to integrate the ...      (Logo: ) ... provide their customers enhanced security to access and ...
(Date:4/15/2016)... DUBLIN , April 15, 2016 ... of the,  "Global Gait Biometrics Market 2016-2020,"  report ... ) , ,The global gait ... CAGR of 13.98% during the period 2016-2020. ... movement angles, which can be used to compute ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... ... , ... STACS DNA Inc., the sample tracking software company, today announced that ... joined STACS DNA as a Field Application Specialist. , “I am thrilled that ... of STACS DNA. “In further expanding our capacity as a scientific integrator, Hays brings ...
(Date:6/23/2016)... , June 23, 2016  Blueprint Bio, a company ... to the medical community, has closed its Series A ... Nunez . "We have received a commitment ... capital we need to meet our current goals," stated ... us the runway to complete validation on the current ...
(Date:6/23/2016)... , ... June 23, 2016 , ... ... exhibiting at the Pennsylvania Convention Center and will showcase its product’s latest features ... will also be presenting a scientific poster on Disrupting Clinical Trials in The ...
(Date:6/23/2016)... FRANCISCO , June 22, 2016  Amgen (NASDAQ: ... sponsorship of the QB3@953 life sciences incubator ... human health. The shared laboratory space at QB3@953 was ... overcome a key obstacle for many early stage organizations ... part of the sponsorship, Amgen launched two "Amgen Golden ...
Breaking Biology Technology: