Last year we had to write essays based on recent publications in Nature Neuroscience, and were then tasked with looking up the background to the paper and writing about the origin and development of the ideas being investigated by the current paper.
Most peoples essays had the format of ‘publication date of paper under disscussion- 2008, previous research it has been based on published in 2007/2005/1990. etc not much beyond 1980. My paper basically followed this pattern.. publication date 2008- previous research.. DARWIN 1872! Seriously, one of his dormant ideas has been practically over looked and not considered scientifically until now.
What is demonstrated here by the authors of this paper, is that the emotional facial expressions of fear and disgust modulate preparedness for perception and action by means of sensory regulation. That ‘disgust’ reduces the availability of sensory information (although not significantly in this paper) whilst ‘fear’ makes sensory acquisition far greater. They refer to this as the sensory regulation hypothesis, it has significant links to the early ideas of Darwin on the function and form of facial expressions, but also appears in sharp contrast to the popular theories of social communication, which stipulate that facial expressions have developed as forms of non verbal communication and not as evolutionary adaptations to the situation, and therefore are not related to ones physiology. However, the sensory regulation theory of facial expression proposed here suggests another role, and has more significant links to other theories of emotion.
In ‘The Expressions of the Emotions in Man and Animals’, Darwin (1872) states that certain mental states will lead to actions that become routine and which are of some service. This is the first principle of function. The second principle, which Darwin referred to as ‘The Principle of Antithesis’, states that when a directly opposite state of mind is experienced, then there is a ‘strong and involuntary tendency’ to perform the movements that are ‘directly opposite in nature’. This is known also as the principle of form. It is these two principles that come under direct scrutiny in the Susskind et al. (2008) paper. These two principles were examined in conjunction with the hypothesis that the form and function of the facial expression of fear has a role in augmenting sensory vigilance.
Few, if any, studies based in neuroscience that look into facial expression have asked the question ‘why is it that specific muscle actions are associated with distinct emotional states’. Why is it that fear looks like fear, and happy looks like happy? Answering this might go hand in hand with other research that focuses on the cross-cultural universality of expression such as Ekman, 1971 and Izard, 1994. ‘Why it is that expressions appear the same universally?’ could be more accurately answered, in terms of their function related to form and origin, which would also explain the world wide commonality seen between expressions and emotions, fear and disgust are universally recognisable even by tribes with little or no western influence trying to identify expressions from images of western individuals.
In line with Darwin’s ‘Principle of Function’, the authors of this paper use this previous research to address an alternative view and build upon a gap in the research, by examining whether the creation of facial expressions can induce similar physiological manifestations of behaviour in the individual creating the expression (the sender) rather than in onlookers (the receivers). Ekman (1999) has also explicitly written about ‘Emotion-specific physiology’ where he states that if, as Darwin suggested, emotions evolved as a means to cope with life tasks then they should not only provide information through expressions to other members of their species to indicate what is occurring, but one would also expect there to be physiological changes that ‘prepare the organism to respond differently in different emotional states’.
Although Darwin (1872) proposed hypotheses which attempted to answer the question of origin, it would appear that past research either took these hypotheses for granted over the years or disregarded them as they became more involved in researching commonalities and purposes of expression in the role of communication rather than looking at form and then relating it to the function for the individual. The reasons for this gap in research seem unclear, perhaps it is because techniques such as computer imaging, and MRI have only been developed relatively recently, and so the principles of function and form can only now be more stringently and scientifically examined and evidence to support them found.
The majority of past papers from which the research question of this paper has evolved from, regardless of differing hypothesis, all appear to share a common origin; the work of Darwin. This surely acts to highlight the significant impact an individual can have on science and the varied directions and developments that a single original idea can undergo in order to better our understanding of complex primate behaviour and cognition.
One more reason to love Darwin.