By: Margaret P. Calkins, Ph.D.

Color Myths:
"Peach stimulates the appetite, so all dining rooms should be peach."

"Old people can't see blue and green, therefore only use warm colors."

The amount of advice being given on colors for older people in general and older individuals with dementia in particular is rapidly growing. Questions about color-what color care facilities should be painted or decorated in-are common at conferences that address design issues for dementia. Unfortunately, like the comments above, most of this advice has virtually no basis in any empirical or even systematically gathered evidence. This article will explore some basic issues about color and its application, summarize what is known about color perception and impact on behavior or mood, and provide some guidelines for color application in dementia care settings.

What you need to know about color
There are two main components that impact how we perceive color. The first is the pigments used on the surfaces we see-the walls, the floor, the table surface, everything in our visual field that we look at. The second is the lighting that is used to provide the illumination which enables our eyes to see these objects. It is important to consider both aspects when dealing with color within the environment. There have been whole books devoted to color theory, so what follows is a very short and basic introduction to color issues.

Color as pigment
Most of us remember mixing paints together as children. The more colors you put together, the muddier and closer to gray the colors got. Pigment colors (as opposed to light, which we'll get to in a minute) are called subtractive, in that when you mixed them together, the resultant colors are closer to black, which is the "absence" of color. There are three primary colors: red, blue and yellow, and three secondary colors: green, orange and violet. They are often seen in a color wheel. Colors vary along three dimensions. Hue is what we typically refer to as color, and is made up of one or more of the primary and secondary colors. Value is the lightness or darkness of the color. A lighter value is called a tint, which is a color with white added, and a darker value, or shade, is the color with black added. So pink is a tint of red and burgundy is a shade of red. The third dimension is chroma, or the brilliance of the color. The primary colors, in their pure form, have the brightest chroma and are the most brilliant. When other colors (such as another primary color or a secondary color) are mixed with a "pure" color, the chroma decreases. Mixing a color from the opposite side of the color wheel (e.g. mixing red with green) produces the lowest intensity or chroma of red, and the color appears neutral gray. Additionally, colors are often referred to as being warm (reds, oranges and yellows) or cool (blues, violets and greens).

Together these three dimensions make up what we typically call "colors." By varying colors along these three dimensions, we can create infinite variety within our world. These variations, when put together, create what is called contrasts. Just imagine what the world would be like if everything were the same hue, value and chroma-if everything were the same color. It would be virtually impossible to "see" anything in the world, because everything would look the same. There would be no difference in the color of the paper you are reading from and the table it is sitting on-there would actually be no printing on the page either, and no shading from light sources to tell you where there were edges on objects. But because colors vary across these three dimensions, there are a number of different contrasts. Itten (1970), an early developer of color theory, described seven contrasts. Only the three that are most relevant for our purposes will be reviewed here.

Contrast of hue is when two different hues (such as red and blue) are placed next to each other. Contrast of light and dark occurs when different tints and shades are placed next to each other. Contrast of cold and warm occurs when colors of different temperatures, such as orange (which is warm) and blue (which is cool) are placed next to each other. As we will see, appropriate use of contrast is probably more important in interior design for people with dementia than specific colors.

Color as Light
Light is essential to perception-without light, we would not see anything. And like everything that surrounds us in the environment, light is made up of colors as well (the same six colors as pigments, plus indigo). The way we perceive color is actually a combination of the pigment color in the objects, and the colors in the light that reflect off the objects in our environment. What the eye actually perceives are the light waves that bounce off objects, and the color we perceive is the color of light that is not absorbed by objects, but reflected off of them.

What's important to know about lighting is that different kinds of light bulbs give off different amount of light waves in the different colors. So how a color is perceived under one type of lighting may be very different that how it is perceived under a different type of light blub. Incandescent and warm white fluorescent bulbs are very warm and radiate mostly red and yellow light. These lamps will intensify warm colors and cool colors will be neutralized. Cool white fluorescent bulbs have more green and blue, and so cool colors in the environment are intensified.

When selecting colors, it is always best to try to look at the colors under the same type of lighting as the room or space the color will eventually be in. In existing environments, this is relatively easy. In new construction, the lamps and lighting fixtures may not be installed by the time decisions about color need to be made. In these cases, determine what type of lamps will be specified for the project, and either find a place that uses these lamps to view your colors, or create a mock-up space where you can install a few lamps of the appropriate type. In generally, it is best to use lamps that have a color spectrum that is close to daylight. There are many of these "color corrected" bulbs on the market. Talk to your lighting designer, or salesperson where you buy your lamps, and ask for lamps that are close to daylight.

Impact of color across the life-span
Studies involving color and light have been conducted for decades, even centuries. While there are many disparate results, there are also come commonalities about color that are worth mentioning. None of the research reported here was conducted specifically on older individuals or people with dementia, but there is no evidence that the impacts would be very different for these individuals. It should also be noted that the research seldom reports what hues or values the research is done with. Therefore, it is impossible to know what "color" was used in the research, and these results should be applied with some caution.

Blue is a restful color with a calming effect . Research suggests use of blue (probably tested by painting a room in various shades of blue) in the physical environment can actually lower blood pressure. It has also been shown that blue (and green) rooms are perceived as several degrees cooler than rooms painted in warm shades (reds and oranges). Blue also increases the apparent size of a space.

Red increase brain wave activity and can stimulate the production of adrenalin into the blood stream. It will also decrease the apparent size of a room, making it look smaller. Red can also increase the apparent temperature of a room, and thus may be useful in rooms that are habitually on the cool side.

Green is associated life growth and life, and is the most restful of colors. Green reduces central nervous system activity and helps people feel calm. Like other cool colors, it makes rooms appear larger.

Violet does not appear to have consistent affects on either mood or the nervous system. This may be because it is a combination of red and blue, which are at opposite ends of the light color spectrum.

Orange is a relatively new color (having appeared in European language only in the tenth or eleventh century). It is closely associated with red, being a warm color, and shares some similar properties. It is also, however, an "earth-base" color, and like green produces associations with nature and natural environments.

Yellow is a highly visible color and thus is often used to carry important messages (road signage). It makes rooms appear larger, and thus is good for small rooms where you want a restful atmosphere.

Color and the aging eye
As people age, there are a number of changes that occur which affect both vision and color perception. This next section will only deal with the changes in vision and perception as they relate to color perception. Of course, many people, particularly men, are considered "color blind" even at a young age. Most typically, these individuals have a hard time distinguishing between reds and greens. Changes in vision and color perception typically begin to occur in the 20's and continue to deteriorate through the end of life. Beyond changes in ability to focus (being near or far-sighted, which in and of itself does not affect color perception), color perception or discrimination diminishes. There is also a thickening and yellowing of the lens of the eye, which is similar to viewing the world through a pale yellow film (approximately the color of ginger ale). This makes it harder to differentiate between colors in the green and blue shades (because green is a combination of blue and yellow). This yellowing also "absorbs" more of the blue light entering the eye (up to 75%), which means things in the environment look much more yellow to an older person than to a younger individual (Baucom, 1996).

There has been some research on color preference, both across the life span and for people over 65. Results are generally very consistent, at least for the top three preference choices, with blue, red and green being most preferred, in that order (Wijk 2001; Reeves, 1985).

Changes with Dementia
There has been little research specifically on color perception in dementia, although there are a few articles that have been recently published. Rizzo and colleagues (2000) compared 43 individuals with mild Alzheimer's Disease (AD) and 22 people without dementia. Basic visual functioning (acuity and motion direction discrimination) was similar for both groups, but the people with dementia scored significantly worse on tests of contrast sensitivity, visual attention and color. Wijk and colleagues (1999, 2001) conducted several tests, and found, not surprisingly, a marked decrease in color naming ability in individuals with dementia when compared with cognitively-intact elderly. Unlike Rizzo's research, there was no difference between the groups on color perception (being able to pick out which color was different when presented three color swatches). Both groups found it easier to distinguish between colors in the red/yellow range, and harder to distinguish colors in the blue/green range. The lightness of the color (tint and shade) was an important factor in being able to discriminate between colors). Color preference ratings were similar for people with dementia as for the comparison group: that is, blue, red and green were most preferred, in that order.

Color application
The data above might suggest that all environments should be primarily blue, red or green. However, it's important to recognize that color preference studies are typically done with small chips of colored paper, which is very different than seeing the color applied to one or more wall surfaces. Nor do these studies explore preferences related to value or chroma, only hue, although Wijk (2001) did find that value (lightness) had a significant impact on color discrimination. Complex issues such as pattern or amount of coverage of color vs. background have not even been considered within the research conducted to date. Despite these limitations, there are still some basic color principles that can be reasonably applied when creating settings for people with dementia.

Principle #1: Emphasize what's important. Within any setting, there are some elements that carry important information, such as orientation cues, or views to interesting vistas or activity areas. Pay close attention to those elements that have the potential to provide useful information to the cognitively impaired individual, and give these more emphasis with brighter colors (using hue, value and chroma), higher contrast with the background, and more light.

- Signage that is meant to be read/interpreted by the person with dementia should be highlighted in this manner, while signage for staff or visitors should be given less emphasis (hues and values that are more similar to the background).

- Provide high hue and value contrast at the edges of stairs or level changes so they are easy for people to see, which can minimize falls.

- When using colors as part of an orientation cue system, remember that older individuals have a harder time distinguishing between colors in the cooler range-blues and greens particularly. Also, many individuals are color blind and have a hard time distinguishing between red and green. Therefore, color is not probably appropriate as the sole differentiating feature between different elements-they should vary in other design features as well. Varying the value of colors (the lightness or darkness) by at least 2 levels on a 10 level gray scale will enable most people will be able to differentiate between the colors.

Principle #2: De-emphasize what's not important. Although this seems like a restatement of principle #1, designers often use color and pattern in ways that draw attention to elements that should be in the background of the visual field. People with dementia struggle to make sense of their environments, and should not have their attention unnecessarily drawn to elements that do not convey meaningful information.

- Floors are an important functional element, not just a surface to be decorated. Avoid high contrasting, bold patterns. Avoid high contrasting borders within rooms or in hallways. Subtle color changes, such as heathering in the pattern is appropriate. Color change at doorways or transitions between rooms is appropriate, although if the change is distinctive (high color or value contrast), it's best to make sure there are handrails for people to hold onto while making the transition. Changes in hue and value often appear to be a change in level which people try to step over.

- If you don't want residents "hanging around" the staff work spaces, make the colors blend in with the background. Remember however, that it is probably the presence of staff that draws residents to these areas more than the color of the space.

Principle #3: Compensate for known visual deficits. Older people requires three times the amount of light to see as well as younger people, but are more sensitive to glare. People with dementia have impaired contrast perception, which makes it harder to see the edges of objects, particularly when the foreground (object) and background are similar color and value. This is particularly important when designing to support functional independence.

- Chair seats should contrast with the floor to people can see where the edge of the chair is.

- Sink basins should contrast with the surrounding counter/vanity top.

- Toilets (or toilet seats) should contrast with both the floor and surrounding walls to make them more visible.

- Table settings should provide high contrast between the plates (usually white or pale colored) and the table/tablecloth/placemat (dark color).

- Colors that are a mix of hues from the opposite side of the color wheel (such as red and green, or yellow and blue) will appear particularly muddy, and thus be less attractive, to older individuals whose lens is yellowed.

Principle #4: Apply color according to known principles. People with dementia may have some unique needs, but they are still people, and no research has yet suggested they respond differently emotionally/visually to colors than the general population. Therefore, the established physiological impacts described in the section on Impact of Color Across the Life Span are probably appropriate for this population.

- Rooms that are habitually too warm that are decorated in cool colors (blues and violets) will be perceived as cooler. Conversely, decorating a cool room with warm colors will make it appear to be warmer than it actually is.

- If space is at a premium and rooms and small and tight, using cooler colors will make them appear to be slightly larger.

- If you want to space to be an "active" place, use warm colors, particularly red, which is physiologically stimulating.

Concluding Thoughts
There is a need for more systematic research on the behavioral/emotional impact of colors on people with dementia, particularly studies that look at color as it is applied in the environment, not just on small swatches of paper. There are some enticing possibilities about being able to create spaces that encourage more activity and participation, or places that are calmer and more restful, but the lack of research hinders designers from being able to apply colors with confidence. There is better knowledge about perception and contrasts, which can support the creation of environments that enhance independent functioning. Clearly, if one can't see a white toilet against white floor and walls, one will have a hard time maintaining continence. Judicious use of contrast, using the hue, value and chroma dimensions of color, should be given careful consideration when creating spaces for people with dementia.

REFERENCES
Baucom, A. (1996) Hospitality Design for the Graying Generation. New York: Wiley Press.
Brawley, E. (1997). Designing for Alzheimer's Disease. New York: Wiley Press.
Itten, J. (1970). The Elements of Color. F. Birren (Ed.). New York: Van Nostrand Reinhold.
Reeves, V. (1985). Color and its effect on behavior modification in correctional detention facilities. In Research and Design 85: Architectural applications of design and research technology.
Rizzo, M., Anderson, S., Dawson, J. & Nawrot, M. (2000). Vision and cognition in Alzheiemr's Disease. Neuropsychologia 38(8): 1157-1169.
Wijk, H. (2001). Color perception in Alzheimer's disease with implications in the environment. In B. Vellas, L. Fitten, H. Feldman, E.. Giacobini, M. Grundman & B. Winblad (Eds) Research and Practice in Alzheimer's Disease, Vol 5. Paris: Serdi Publisher.
Wijk, H., Berg, S., Sivik, L &Steen, B. (1999). Color discriminationm color naming and color preferences among individuals with Alzheimer's Disease. International Journal of Geriatric Psychiatry. 4(12): 1000-1005.

Reprinted with permission: Journal of Dementia Care, Vol 10, No. 4. Hawker Publications, 2nd floor, Culvert House, Culvert Road, London, SW11 5DH. 020-7720-2108