Psychotextiles and their interaction with the human brain

Abstract

This work crosses the boundaries between design and technology, and it focuses on pattern design, its relationship with neuroscience and how new SMART products can be developed from this interaction. What we see in our environment has significant influence on our emotion and behaviour. A simple shape and form is able to impact on our emotions. This research has explored the emotional effect evoked by different visual pattern characteristics. Two paired pattern categories were investigated: repeating/non-repeating and weak/intense. Repeating patterns contain regularly repeating elements and have symmetrical and continuous features; in contrast, non-repeating patterns contain irregularly repeating elements and have asymmetrical and discontinuous features. Weak patterns are faint, light and simple compared to intense patterns that are high in contrast, bold and complex. The emotional response to each type of pattern was investigated directly by brain and cardiac activities of twenty subjects by electroencephalography (EEG) and electrocardiography (ECG) measurements and by self-evaluation; the former is used to measure the brain wave activity, and the ECG to analyse the heart rate changes. These physiological signals were then analysed, interpreted and correlated with people’s self-evaluation of their emotional response to the pattern. It was found that repeating patterns produce a more pleasant sensation than non-repeating patterns, and intense patterns evoke a higher level of excitement than weak patterns. The significant changes in the emotional effects found by changes of pattern and the good correlation of the objective and subjective emotional measurements encouraged the implementation of pattern change by design and production of SMART fabrics. Four knitted fabrics with the ability of switching their pattern appearance from repeating to non-repeating, and from weak to intense have been successfully produced with a purpose made electrochromic composite yarn. The emotional effects of pattern-changing of these fabrics have been further investigated. The notion of influencing human emotion by engineering the pattern design and characteristics of SMART textiles is established and these fabrics are named Psychotextiles. Finally the event-related potential (ERP) investigation of the visual brain (no thinking, or memory) revealed that there may be an influence on human emotional effects in less than 1 second from the time of seeing the object; a time sufficiently short for these to be little analysis within the brain.