And so much waffle is written well-nigh how colour affects us. You hear how one hue can create a calming effect, while another volition provoke passion, or the similar, without a shred of evidence to support the claims. Pattern decided to go to the lesser of this and find out but how much measurable scientific proof at that place is of the result of colour in the built surround. We teamed up with Milliken Carpets, which commissioned colour adept, Byron Mikellides, Emeritus Professor of the Place, Civilization and Identity Research Group at Oxford Brookes University, to tells us what empirical knowledge exists on this subject

Blueprint

Words - Byron Mikellides

Illustration - Martina Paukova

Over the years many books, studies and various research publications have reported how color affects our visual perception, making objects look heavier or lighter, planes advance or recede, interior spaces feel warmer or cooler, calmer or more than heady, and fifty-fifty sounds seem softer or louder. We know that color can exist used decoratively and symbolically based on the richness of cross-cultural community and practices. Colour is also part of nature's survival kit for the functions of camouflage, allure, protection or alarm.

There are many extravagant claims for colour as a solution to design and architectural issues and problems, but what has actually been scientifically proved?

Colour and Psycho-physiological Arousal

In both scientific and aesthetic studies, colours accept been classified and grouped in various ways. One of the well-nigh widely held groupings is that of 'warm' and 'cool' colours. Hues such every bit red, orange and xanthous are seen in add-on to their warmth, as beingness exciting and stimulating, whereas hues such as blue, turquoise and green are seen, in addition to their induced coolness, every bit beingness calming and relaxing. Applications based on these perceptions of colours are not confined to the piece of work of architects and artists, just also, for instance, to clinicians in an attempt to pacify or calm down aggressive and anxious patients by using bluish and green colours.

In the U.s., blue and light-green colours were used in Alcatraz before the prison house was closed in the early on 1960s. Conversely almost, in the 1980s and 90s, a candy pinkish, which became Bakery-Miller Pink (named after Seattle Naval Correctional Facility directors, Baker and Miller, where they tried it out on inmates) was used in penitentiaries and later on in Britain detention cells to supposedly calm downwardly aggressive inmates. Only are these decisions the results of experimentally derived data?

effect of colour in the built environment - the scientific evidence

The design of any experiment is crucial and must take into account such variables every bit the historic period of the participants, the duration of colour exposure and the content and context of color stimulation. Furthermore, individual differences such equally personality can produce differential effects. For example, the British psychologist Hans Eysenck, has claimed that extroverts take lower levels of arousal than introverts, and that introverts are more susceptible to external stimulation. In an earlier experiment in 1986, Rikard Küller found that the heart rate was slowed down by as much equally 10% in the most introverted participants. And then, colour and complexity of the visual field tin have varied differential effects.

Current research uses unlike color stimuli and different methodologies for studying the furnishings of colour on humans. These are measured either cognitively or physiologically. The question of whether cerise is a more than activating colour than bluish has been studied using two different stimuli. One is color light and measured by physiological changes in the primal and autonomic nervous system and the other is colour pigment applied in interior and exterior spaces while varying the dimensions of hue, chromatic force and lightness using photo simulation, and measured by subjective and cerebral responses.

In other experiments subjects accept experienced realistic full-scale red and blue spaces where both physiological and cerebral measures are taken. Work has also been done looking at whether differences in colour (the Hue Heat hypothesis) bear upon our perception and feeling of warmth at the cognitive as well as the physiological level.

Rikard Küller's (1981) mammoth Annotated Bibliography of i,700 references, deputed by the Commission Internationale de 50'Eclairage (CIE) summarised the psycho-physiological literature on colour activation, and firmly established the importance of three systems, mediating the non-visual furnishings of light and colour.

First, the cutaneous system activated when ultraviolet and infrared radiation reaches the skin; peel pigmentation, and the evolution of vitamin D are some of the main furnishings. Secondly, the pineal-hypothalamic-pituitary system - low-cal affects the pineal gland where it blocks the sleep hormone melatonin, which in turn influences the hypothalamus that is involved in our emotions. Thirdly, the reticular activation system, where visual stimulation passing through the reticular formation activates the central nervous system as a whole, controlling everything from mood to motor skills.

effect of colour in the built environment - the scientific evidence

Critics of the studies have suggested that the effect of hue on warmth and excitement is an intellectual one, involving cognitive processes, and is not based on physiological processes which affect the whole organism. In an attempt to answer this type of criticism, namely, that the effects of these colours are non only just based on stereotyped verbal associations, but that different colours actually evoke different feelings and emotions affecting the unabridged organism, American Robert Gerard, in his classic study in 1958, concluded that the two wavebands of radiant energy at the opposite ends of the visible spectrum -- blueish and crimson -- exert a differential biological influence on the organism equally measured by general activation in the cardinal and autonomic nervous system (electrical brain action, blood pressure, respiration, and heart rate). The reason for mentioning this old study here is that it was the first scientific one to employ physiological measurements to study the furnishings of colour on people.

Farther support is given to Gerard'southward work by an experiment carried out by Ali MR (1972). Blueish and cherry were projected directly on the eyes for half-dozen minutes and brain activity was recorded throughout the period. The results of this study showed greater cortical arousal following the presentation of blood-red light and lower cortical arousal following a blue light.

Parallel to these attempts using physiological measures there has been a different approach to institute the meanings people associate with different colours. This approach differs significantly from the higher up in that the three dimensions of colour (hue, chromatic strength and lightness) have been systematically manipulated in an effort to ascertain their human relationship to the dimensions of colour meaning. Also, the obtained data was treated past more powerful methods of statistical analysis such as factor and cluster assay, which were non bachelor to the early researchers.

In 1970 Lars Sivik from Sweden was the first to demonstrate, with a technique of photo-simulation, that it was not hue which affects how exciting or calming a colour is, only the chromatic strength of each hue. Later, in 1972, Acking and Küller, too from Sweden showed, with the use of perspective drawings of interior spaces, and afterward on in full-calibration spaces, that weak colours give a room an impression of calmness, while strong colours projection an impression of excitement.

There are, however, some fundamental differences between the two sets of studies. In the first two studies (Gerard and Ali) the content of colour stimulation was coloured light, while in the last two studies (Sivik and Acking & Küller) the content was colour pigment. Furthermore, in the first two studies, subjects experienced the colour light stimulation in an abstract course in the laboratory, while the final two studies were carried out in the context of real interior and exterior spaces.

These two approaches were covered in the outset edition of Colour for Compages (1976), which I co-wrote with my colleague Tom Porter. In an attempt to bridge the gap between these sets of experimental approaches I carried out an experiment with Rikard Küller, the results of which announced in the updated edition of Colour for Architecture Today (2009). In this experiment, both physiological likewise equally cognitive reactions of people were measured using real life spaces as opposed to colour slides or drawings. Colour pigment was used as opposed to colour light to represent the sort of spaces we really experience for longer periods of time. The primary technique used in this experiment to mensurate activation was through Electroencephalogram (EEG).

When a person is awake but relaxed, blastoff rhythm abounds. This rather ho-hum, high amplitude rhythm has a trend to disappear when the person is stimulated, but returns when the person is relaxed. Too much stimulation results in continuous blocking of alpha, involving the whole nervous system, a state mostly referred to every bit stress. Thus, by measuring the proportion of alpha in EEG, information technology is possible to find out whether an environment is nether stimulating or over stimulating.

ECG (Electrocardiogram) has also been used as an indicator of activation and stress. ECG measures changes in pulse rate and arrhythmia-variation of heart rate of the autonomic nervous arrangement regulating the functions of internal organs. We are often unaware of these changes because they function involuntarily. For the experiment at the Environmental Psychology Unit, School of Architecture of the Lund Institute of Engineering science in Sweden, ii rooms were used, i red and 1 blue, with an bordering control room where the monitoring equipment used for the experiment was placed.

The most of import result of this written report is that as far equally cortical arousal is concerned there is positive support to the hypothesis that red is a more than activating colour than bluish as indicated by departure in delta frequency and the strong tendency in alpha. Delta rhythm is indicative of a drowsy country and characterised past high amplitude, low frequency waves; the difference between the 2 colours in delta was observed in both hemispheres of the encephalon during the first and second hr of colour exposure. As far as cortical action is concerned the results of this experiments support, in a qualified way, the previous results of Ali (1972) and Gerard (1958) with coloured light.

In the autonomic nervous organization, however, the moving picture is very unlike. In this experiment, pulse charge per unit was higher in the bluish room at 71.5 beats per minute and lower in the red room at 68.4 beats per infinitesimal. These results are in the opposite direction to the hypothesis stated by Gerard. The only other colour study which offered an alternative hypothesis to heart rate was that of Küller (1976). In observing that centre rate was slower in a colourful room than in a grey ane at one-hour, two-hour and three-hour intervals, he put forward the hypothesis that cortical arousal is accompanied past cardiac deceleration. And so it could be argued that strong and highly saturated colours, especially ruby can put the brain in such an excited land every bit to cause the slowing of the center charge per unit.

Another interesting finding is in the example of arrhythmiavariability of heart rhythm -- this was higher in response to cherry-red than bluish. The combined employ of variability and level of center rhythms is a novel mode of evaluating the autonomic residue, which merits further investigation.

There are several theoretical implications as well as practical applications of this research. At the theoretical level, the validity and reliability of the diverse cortical and autonomic measures are brought into question. The link betwixt EEG and ECG too as their relationship to cognitive measures is also of theoretical involvement. The hypothesis regarding cortical arousal and cardiac deceleration likewise deserves more experimental work.

effect of colour in the built environment - the scientific evidence

At the practical level, chromatic strength was shown to be important at the cerebral-affective level. Lars Sivik stated that 'green is no more calming than carmine if we compare the same saturation and lightness'. First impressions are of import to architects and designers, however, longer periods of upward to two hours testify differences in hue affecting our body at the physiological level as far as cortical arousal is concerned. The paradoxical slowing of the heart rate and its inverse relationship with arrhythmia is not still resolved and requires an ambitious undertaking and cooperation of several research groups.

Colour and the Subjective Feeling of Warmth

There are alien directives betwixt color connotation studies and laboratory experiments with regard to the importance of hue on the subjective feeling of warmth and heat.

Although blue is considered cold and cool, the blue of a gas flame is hotter than that of an orange or red flame. Indeed when James Turrell, the renowned American artist and psychologist, gave the keynote address to the AIC International Conference in Oslo prior to the new millennium in 1999 he made the impassionate plea to 'stop teaching the colour wheel unless you lot are going to teach the spectrum'. He went on to say, 'End teaching colour symbology. Ruby is not warm, and cool is not blueish, it is simply the opposite.'

The problem is that all the anecdotal reports claiming that red is a warm colour and bluish a cold colour are strongly supported by the vast bulk of the published perceptual and cognitive studies (Morgan & English language 1926, Sivik 1974, Hogg et al 1979, Hutchings 2007). These studies used colour samples, simulated color spaces in the form of colour slides and drawings, or coloured light in a variety of contexts. The correlation of their findings shows that fourth dimension, gustation, culture or other intervening variables could not have been responsible for the consistency of their findings.

What are the implications of these studies for the designer of the built surroundings? In that location is no doubt that the inducement of visual warmth by exposure to red calorie-free or scarlet paint is elicited in a diverseness of contexts. Men and women from various cultures and various ages report this apparent warmth consistently, and as such it has straight blueprint implications for the professional.

Architects are involved not only in designing buildings but also in creating spaces with sure perceived qualities and atmosphere. By manipulating the hue dimension they can create a infinite which people will perceive as warm or common cold at the cognitive level.

The but study to give limited back up to the Hue Rut hypothesis was by Fanger, Breum and Jerking (1977) though the difference in perceived temperature associated with colour were extremely small at 0.four°C, and was argued past the experimenters to be of no practical significance. This study, even so, supports the notion that apparent warmth along the line of the perceptual studies may accept some basis at the physiological level, which could be detected past the development of more refined techniques in the future.

James Turrell's strong plea to finish teaching 'color symbology' adds some other interesting dimension to the debate. Perhaps, the lack of conclusive laboratory experiments to date in support of the Hue Heat hypothesis reflects the distinguished British perceptual psychologist Richard Gregory'due south statement (2005) that 'there is a conflict between designing experiments simple enough for analysis and sufficiently circuitous to reveal the full richness of phenomena. So science is an art. Like art it is non completely mastered.'

In conclusion

At that place are many respectable, scientific investigations, observations and analyses on the perceptual aspects of colour and color interactions in 2D and 3D space, however many experiments on color connotations are awaiting further validation, and cross-cultural comparisons. We have systems of colour notation, such as the NCS based on colour phenomena and scientific color theories, but nosotros have not progressed far on experiments involving colour neurophysiology and experimental psychology because of the difficulties and expense involved in conveying them out and the lack of medical facilities and interdisciplinary research within university departments cooperating with schools of architecture. This is a subject area which should be considered much more seriously than at present.