Light and Colour

Colour exists in every part of the Universe; it is around us everywhere and we are influenced by colour constantly whether we realise it or not. Even when we have our eyes closed or it is dark, we still see colour. Even when we dream, we see colour.  Colour seems to describe life – evoking senses, feeling and memories.  We use colour to describe our feelings such as ‘feeling blue’ or ‘in the pink’, ‘green with envy’ or ‘seeing red’.  We are aware that some colours lift our spirits whilst others hide just how we are feeling.  Colours can be exciting, motivating, inspiring or balancing, calming and nurturing.

Where do these feelings come from?  We learn to differentiate colour at an early age.  Naming each one correctly can be a very young child’s ‘party piece’.  The ability of identification and naming colour is stored in the cortex of the brain, the area that governs formal education. The reflexive, instinctual response to colour is stored in the primitive, mid-brain area.

Colour is the visible section of the wavelength of light. The wavelengths of visible light (colour) lie between 400 and 700 nanometers (a nanometer is one billionth of a meter).  As the wavelength gradually increases from 400 to 700 nm, it is perceived as violet through the spectrum to red. (The wavelength is lengthening and slowing as it moves towards 700nm.)  We perceive coloured objects as a result of the photons, which make up the wavelength, being absorbed or reflected by that object.  A coloured object will absorb all the wavelengths (colours) that exactly match it and reflect the rest.  This is what we see.  Therefore, a red tomato absorbs all the rays except the red one that it reflects, so we see it as red.

Science recognises the effect of x-rays, ultraviolet rays and microwaves on our physical bodies but finds difficult the idea that our emotions and thought processes could also be affected. Light plays a major role in stimulating and regulating our physiological responses.  Therefore, as colour is the way in which we perceive light through the various wavelengths, it clearly can create different psychological and physiological effects.  Dr. Max Luscher, a leading colour expert, believed that a personal colour preference or dislike indicated a particular state of mind and/or a glandular balance. This, he believed, shows the reaction to be part of the ancient primal memory.

As science techniques have become more sophisticated, it has been shown that certain regions of the brain are light sensitive and respond differently to different wavelengths.  It is believed that these different wavelengths of radiation (colour) act on the endocrine system to affect hormone production.

As early as 1942, Russian scientist S V Krakov found that the colour red stimulated the sympathetic portion of the autonomic nervous system and blue stimulated the parasympathetic portion.  Robert Gerard, who tested a group of normal adult males, confirmed this in 1958.  By shining a red light onto a screen in front of the group, an increase in blood pressure, respiration and eye blink rate was noted.  When a blue light was shone, a marked reduction in these rates was recorded.  The heart rate in both cases remained unaffected. On an emotional level, blue increased feelings of relaxation and lessened anxiety and hostility.  The colour red increased excitement and tension.

Put simply, these experiments indicate that the autonomic nervous system and the part of the brain connected with vision become more active when stimulated by the red light and less aroused by the blue light. Clear, white light was used as the control and consistently indicated no difference either way.

Further experiments during the early ‘70’s have shown that specific colours will affect moods, breathing and pulse rate and blood pressure.  The colours that can increase each symptom are yellow, orange and red (red having the minimum effect).  The colours that can decrease each symptom are black, blue and green (green having the minimum effect).

Colour is used today as a tool to aid health in hospitals.  The maternity wards will use blue light (450nm) for the treatment of jaundice in newborn babies.  The light breaks up the biliruben that accumulates in the body and allows the natural processes to eliminate it.

This same blue light has been to be effective in reducing arthritic pain in experiments conducted in 1982.  A study in San Diego headed by Dr. Shanon McDonald showed that the light could positively affect the pain levels in a group of middle-aged women with rheumatoid arthritis.  The levels would vary with the length of exposure to the light.

Dr John Anderson conducted experiments using red light on migraine sufferers.  By flashing red lights into the eyes of sufferers a substantial amount had no migraine after one hour and the rest felt an improvement in symptoms.

(Further reading and bibliography notes – Light, Medicine of the Future by J Liberman)