[T]here are unique features of individual perception that have important implications for the design of information. […] designers must search for some areas of commonality.”  (Whitehouse, 1999:103)

Oliver Sacks’ accounts of visually impaired patients demonstrate the nature of perceptual experience as essentially idiosyncratic. This “perceptual fingerprint” is identified as the difference between seeing and understanding, between vision and cognition. Roger Whitehouse categorizes perceptual processes as follows: sensory mechanisms which are defined by individual sensory receptive capabilities (i.e., retinal and eardrum functions); cognitive processing of sensory inputs which depends on individual neural wiring; and ascribed meaning to perceived sensory inputs which results from individual experience and cultural background.

As babies, we leave a womb where we receive little sensory stimulation and, with all our sensory input devices in full working order, emerge into an explosion of light, color, sound, smell, noise, movement, touch–sensations that have absolutely no meaning for us.” (Whitehouse, 1999:108)

Because we possess the ability to adapt and change in accordance to changed environments, we are in a position to perfect our physical and mental competencies. This is due in part to the fact that behavioral interventions are also metaphysical; they affect specific areas of the brain and produce physical changes. In fact, the neuroscientist Micheal Merzenich (2004) described the brain’s evolution as twofold: in childhood, the brain learns to adapt to its environment as it absorbs information directly. He calls this the ‘critical period.’ In the second period, the ‘adult plasticity,’ the brain is able not only to adapt, but also to control its behavior and change at will. The brain is then a volitional entity. By presenting the areas of the brain in the form of a geographical map, he demonstrated how the brain remodels itself in ways that are skill-specific (such as posture, movement, etc.). This also confirms Sacks’ (2009) hypothesis that there may be specific fractions in the brain responsible for specific sensorial activities such as pattern recognition. Sacks’ findings showed that patients under certain medical conditions had experienced geometrical, musical, mobile and psychotic hallucinations involving all their senses in coherent ways. Hence, every brain has its idiosyncratic geography. Merzenich noted that “the embodiment of You” is the greatest determinant of how one’s brain might look. Physical change that occurs in your performance with the world, then, occurs as well in the physical configuration and remodeling of your brain structure.

The contextual scale of information matters; that is, to design at the human scale with considerations for accessibility, readability, and reachability, that correspond to user-centric demographic and psychographic requirements. To design for user-centric perceptual processing is to coherently integrate a belief system. Whitehouse explains how belief may contribute to the ways in which information is assimilated and interpreted, thus affecting the understanding of what one sees.

Shifts in perception are borne out of our ability to adapt, learn, and change unique perceptual beliefs. Change abounds when new skills are achieved and hidden skills are discovered in the course of adapting to contextual circumstances whereby newly-made associations and patterns are established in the mental realm and henceforth shed light onto and transform every preconception and belief one might have had –often referred to as “paradigm shifts”: when one’s whole world is reconsidered and tailored again to fit a new reality. To understand and respond to users’ unique perceptual belief, design needs to shift priorities to meet user-centric design goals that allow for the generation of friction-free solutions that facilitate behavioral, sensorial, and cognitive information consumption.

To achieve effectiveness and efficiency, the design process involves: preliminary user research and observation, defining the problem that requires a design intervention, providing multiple solutions or proposals that address the problem in question, usability testing protocols (determining number of participants, duration of test, types of tests, collect responses, debriefing with users), redesigning according to test results or user responses, etc. Designing for usability methodologies lead to a comprehensive, effective and efficient design solution that responds to users’ perceptual processing needs and expectations.

By simple testing and observation, […] we became aware of some of the practical implications of individual perceptual differences. Most importantly, we began to understand how easy it is to disenfranchise individuals simply by not perceiving and correctly interpreting the most basic facts about their needs.” (Whitehouse, 1999:128)

Whitehouse encourages designers to actively include user cognitive differences by engaging in “the extraordinary value of” user research and usability testing to understanding users’ needs as well as cognitive and cultural requirements.

source:

Merzenich, Micheal. “Exploring the Rewiring of the Brain.” Filmed February 2004.
Source: http://www.ted.com/index.php/talks/michael_merzenich_on_the_elastic_brain.html
(Access Date: December 3, 2009)

Sacks, Oliver. “Hallucinations.” The Robert B. Silvers Lecture, The New York Public Library.
Date: September 21, 2009. Source: http://www.nypl.org (Access Date: December 3, 2009)

Whitehouse, Roger. “The Uniqueness of Individual Perception” Information Design. Jacobson, Robert (Ed.). MIT Press, Massachussets: 1999, pp. 103-129