As architects and designers, we are well aware of the impact that our physical environments can have on our psyche. From feng shui to beaux arts, from glazing to street trees, design has always played a role in how people feel in their spaces and places.
T o help measure how design can really impact our emotions, a recent study by mathematician Nikos Salingaros of the University of Texas (Journal of Biourbanism, 2012; 2, 11) collated and quantified the effects these design choices can have on the human mind.
His findings showed that not only can complex designs, specifically fractals, reduce stress levels, but in contrast, simple and minimalist designs can actually increase stress levels.
What’s a fractal?
Fractals are hierarchal patterns. Instead of geometrically simple forms like rectangles or parabolas, fractals generally have spikes or granules, a sort of hairiness with varying degrees of complexity. Fractals also have what’s known as self-similarity: a similar or repeated structure can be found at increasing and decreasing magnifications. Much, if not all of the natural world around us are based on fractal design.
Unsurprisingly, these patterns can be found in all sorts of traditional manmade artifacts and structures, from textiles to temples. For example, a 2006 study of Mesoamerican pyramids found that not only are these structures based on fractal design, but they also have a fairly specific fractal range (dimension between 1.38 and 1.23). These patterns are common throughout history and across the world.
But during the 20th century, a distinct divergence occurred in art and architecture. Modernism, consciously seeking to break away from all of human history and traditional design, focused instead on pure forms, clean lines, and a distinct lack of ornamentation. Complex, age-old fractals fell out of fashion.
Simplicity versus Complexity
Salingaros compiled and analyzed a series of studies which compared stress levels of workers surrounded with varying degrees of complex designs. Minimalist, colorless, and abstract (non-fractal) designs were found to cause the greatest increases in human stress levels.
In contrast, a drawing of a savannah and geometric designs tended to reduce stress levels. Not only did these designs reduce stress levels, but cognition and problem-solving levels also increased with the test-subjects.
After further analysis, it turned out there was a correlation between the underlying semi-complex fractal patterns in these designs and the lack of fractals in the minimalist designs, and resultant stress levels.
Specifically, Salingaros showed that semi-complex fractals, specifically fractals with a dimension of 1.4, provide the most calming visual designs on the human mind.
Fractal Dimension 1.4
As explained in the paper, fractals can be repeated at varying degrees of complexity. A smooth line, either straight or curved, has a dimension of 1 (low-dimension), while a two-dimensional space that is completely filled has a dimension of 2 (high-dimension). The von Koch snowflake, on the right, has a dimension of 1.26 and would be considered mid-dimension:
The Vicsek fractal has a dimension of 1.46:
The Douady Rabbit fractal has a dimension of 1.39:
Fractal Tuning and Cognitive Resonance
While I don’t intend to copy the entire paper here (I suggest you follow the link above when you have some time), Salingaros provides some potential hypotheses as to why our brains react positively to specific fractals:
- The brain itself is fractal, not only physically, but in how and where it stores associative memory points.
- Fractal physiological structures could be more in-tune with fractal structures in the external environment, like an antennae.
- Mid-level fractals could convey the survival advantages of our ancient savannah origins. High-dimension fractals, such as dense forests, could hide predators, and low-dimension fractals, represented as plains, are too open and exposed.
- The eye uses a mid-range fractal path to scan stimuli, following regions of high contrast. This is known as Lévy flight, and is a similar pattern to those of foraging animals.