Lighting the Way: Project Prakash Opens Our Eyes to a World of Humanitarian Research

In America, we all know Helen Keller. But we don’t know the more than 200,000 blind children in India1. We don’t know that blind children in India do not go to school; that many end up begging on the streets (if they are of the “lucky” half that survives past the age of five). We don’t know that many of these blind children have easily curable disorders, like cataracts. But Pawan Sinha, founder of Project Prakash (meaning “light” in Sanskrit), saw what we have all been blind to. He saw a chance to help these children by providing free medical treatment to restore their vision. However, because the brain's ability to process visual information emerges early in development, there was one question that Project Prakash would need to answer: After removing cataracts from an older child, would the brain still possess the ability to learn how to interpret visual signals in order to recognize objects?

 Fig. 1 A cloudy lens prevents light from reaching the back of the eye.

Fig. 1 A cloudy lens prevents light from reaching the back of the eye.

Cataracts are one of the most common forms of curable blindness2. In order to see, our eyes have retinas (cells at the back of the eye that take in light)3. The retina then turns this light into neural signals that travel to the brain. The retina must receive a sharp image of the world in order to produce a clear signal to send to the brain (where the information is processed). To ensure this image is clear, the lens of an eye focuses this image. However, cataracts cloud the lens (as seen in Fig.1). This prevents light from properly reaching the retina, causing blindness.

The brain learns to recognize objects by determining which parts of an image belong together and which parts represent different objects. Our brains learn that parts of an image with common levels of brightness or other shared traits tend to belong together (are grouped)5. However, in the case of newly sighted children, this grouping is ineffective and subsets of objects, or even shadows, will be perceived as entire objects themselves (Fig.2). The children’s brains do not yet know how to interpret signals sent from the retina.

In the past, many older blind children in India were denied treatment because late development of visual processing was not believed to exist. Thanks to Project Prakash, this is no longer true.

 Fig. 2 A newly sighted individual would identify at least six objects in this image—the shadows are interpreted as separate objects.

Fig. 2 A newly sighted individual would identify at least six objects in this image—the shadows are interpreted as separate objects.

By providing treatment to older children and studying how their visual processing develops, the Project Prakash researchers were able to show that brains of the previously blind children likely use motion to learn to identify objects. Motion allows the children to separate an object from the background and identify the boundaries of the object. After the brain first learns to identify objects by motion, it builds on this foundation and the children are eventually able to identify nonmoving objects purely by features like color or orientation. Project Prakash ultimately demonstrated that there is no critical period beyond which visual processing can no longer develop6.

Project Prakash affords the opportunity to answer questions about vision that have typically been constrained to testing in infants (older children with curable forms of blindness simply do not exist in the United States). These past experiments were limited by the rapid development and limited comprehension of infants. Moreover, Project Prakash’s humanitarian efforts are intrinsically linked to its developing research.

Project Prakash transforms the lives of children with curable blindness. Junaid, treated at age 14, was able to finally receive an education and has since passed his 8th standard exam. Farana, before profoundly blind, can now walk independently. These are just two of the almost 2000 children treated. While these children just represent the tip of the iceberg, this marks an exciting start to Project Prakash’s proclaimed goal: Illuminating Lives, Illuminating Science. With continued collaboration, this light will continue to spread.

Sources:    

 [1] “Project Prakash. (n.d.). Retrieved February 20, 2017, http://www.projectprakash.org/

[2] Cataract. (n.d.). Retrieved February 20, 2017, http://www.preventblindness.org/cataract

[3] Watson, N., & Breedlove, S. (2016). The Mind's Machine: Foundations of Brain and Behavior (2nd ed.). Sunderland , MA: Sinauer Associates.

[4] Gilbert, C. (Photograph). (1998) Mature cataract in a child [photograph].

[5] Enns, J. T. (2006). Perception, Gestalt Principles of. Encyclopedia of Cognitive Science. doi:10.1002/0470018860.s0054

[6] Trafton, A. (2012, June 19). The gift of sight and the science of seeing. MIT Technology Review.