LIGHT

A use of light and shadow can also create aesthetic designs

Staff in offices with no natural daylight have been shown to sleep 46 minutes less than those with daylight, on average

Left: from the project Homo Technologicus by Isra Safawi - a visual commentary on the integration of digital technology into our lives and how this impacts our habits, lifestyles, health and environment Sadly, being glued to phones and laptops is no longer something that only younger generations are guilty of. Most of us know, all too well, the pain of headaches, eye strain and a struggle to get to sleep if we stare at our screens for too long. But, what is the impact of lighting in the enclosed spaces that we spend most of our time in? We increasingly see buildings built with less windows and more artificial light. Not only is natural light aesthetic and comforting, a lack of it can often be disorienting, and even distressing, as building users have no reference to the outside world, time or weather.

The colour of natural light changes subtly throughout the day: from warm, orange hues at sunrise and sunset to cool, blue hues during the day. Vital for physical and mental health, humans have an internal body clock (circadian rhythm), that synchronises our minds and bodies to the sunrise-sunset cycle. In the evening, this causes an increase in melatonin production, a hormone that regulates sleep. Whereas the shift to blue-white light during the day is a trigger for wakefulness, as levels of cortisol and histamine increase. A disruption to the natural levels of these key hormones and chemicals in the nervous system could result in unnecessary stress on a range of systems in the body. This could even increase blood pressure, cause digestive issues and result in anxiety or depression.

High lighting levels in buildings (where lower energy consumption light sources are likely to be of a blue hue) at night is an example of an inappropriate environmental cue that can reduce melatonin production, leading to poorer sleep quality. This also lowers the release of histamine in the morning, making us feel drained and unenergized, effecting mood and productivity. As if it couldn’t get any worse, cortisol levels are also excessively raised, causing stress and inflammation.

Whilst still making sure to give users control over their surroundings, building design can help to rectify this modern issue through the simple use of glass windows (preferably with a view to nature). Although, the accompanying heat gain or loss must be considered when designing. Also, remember that lower floors get less sunlight; deep spaces create dark areas at the back of the room; and rooms that require privacy (i.e. bathrooms) should have higher level windows.

SAD TIMES

Above: the ideal daily cortisol and melatonin cycles, as part of our circadian rhythm

SAD is a form of depression. Symptoms include:

• Tiredness and lack of energy • Anxiety • Loss of libido

• Overeating • Problems concentrating • Irritability • Problems sleeping • Feeling tearful and sad

Seasonal affective disorder (SAD) is a type of depression that is mostly related to changes in the seasons. It can make you feel unenergized and moody. Whilst many experience the symptoms of SAD, it hasn’t always been taken as seriously as it should be. Although the exact causes of SAD are disputed, it has often been linked to a reduced exposure to sunlight (hence the seasonal aspect) and, therefore, disrupted circadian rhythms. It is thought that melatonin production becomes higher than normal, making those with SAD sleepy throughout the day. On top of this, a lack of sunlight may lead to lower serotonin levels (one of the ‘happy chemicals’), which can affect mood, appetite and sleep.

‘Bright light therapy’ can be used to aid people with sleep issues and SAD. This ‘re-sets’ the circadian clock, but this must be maintained by regular sleep patterns. In the same way that sunlight does, the therapy exposes the eyes to safe amounts of light for a specific and regular length of time. However, it must be carefully delivered during the daytime, with considerations of the time of year and appropriate light wavelengths (to get the shifts between

Image by iconiclights.com

orange and blue light). The improvements to sleep are crucial for memory consolidation and the resolve of emotional issues. With increased motivation, attention and cognitive performance, alongside a ‘happier’ mental state, benefits could be seen across healthcare, commercial and educational settings.

In case reduced sunlight truly is the cause of SAD, buildings must try to maximise its users’ exposure to sunlight, through windows for instance, as a precautionary measure. To accommodate those who already experience SAD, the use of ‘smart lighting’ is becoming more widely available. The ability to replicate the subtle changes in natural light to synchronise our circadian rhythms is a great example of how technology and artificial intelligence can aid wellbeing, rather than over-controlling human life. Where there are budget constraints, buildings can strategically use light bulbs of different temperatures to mark spaces for different purposes; study, relax, work, sleep. For example, in areas that call for the alertness of users, such as in an office or school, blue-white light could be used. Whereas, in areas that call for a calm and relaxing atmosphere (such as bedrooms), soft-white light (with the orange hue) can be used, as it triggers the release of melatonin.

2 million people are thought to be effected by SAD in the UK and Ireland

Mild forms of SAD are called ‘winter blues’

Soft-white light can be used in bedside lamps to trigger melatonin for a better sleep

Strategically placed windows

can expose building users to natural light

Design by BuckleyGrayYeoman