Green Love Is Ugly – One Person Out Of Every 1,000 Has Synesthesia
Surprising as it may seem, there are people who can smell sounds, see smells or hear colours. One person out of every thousand has synesthesia, a psychological phenomenon in which an individual can smell a sound or hear a color. Most of these people are not aware they are synesthetes: they think the way they experience the world is normal.
Actually, all of us, at some point in our lives, have had this skill (some authors affirm that it is common in newborns). This phenomenon, called “synaesthesia” – from the Greek “syn” (with) and “aisthesis” (sensation) – consists of the pairing of two bodily senses by which the perception of a determined stimulus activates a different subjective perception with no external stimulus (in science, the evoker stimulus is called inducer and the additional experience concurrent).
In the department of Experimental Psychology and Physiology at the University of Granada, a research group is carrying out pioneering work in Spain on the systematic study of synaesthesia and its relation with perception and emotions. Professor Juan Lupiáñez Castillo and Alicia Callejas Sevilla have devoted many years to the study of this unknown but interesting phenomenon.
Callejas’ doctoral thesis covers the various forms of synaesthesia focussing on the most common one: the grapheme-colour type (for people with this form of synaesthesia, letters, words and numbers evoke colours in an automatic and involuntary way).
One of the distinctive characteristics of this form of synaesthesia is the fact that people are certain about their perceptions: they feel that their way of experiencing the world is correct, and they become disappointed when they realize there is something that is not quite right. ‘Therefore, when a person with grapheme-colour synaesthesia indicates that the word table is blue, it is quite probable that if he or she ever sees the same word written in a colour other than blue, this word will appear to him or her as wrong and consider it a mistake. The synaesthete might even point out that the word is ugly or that he or she does not like it because it is not correct,’ affirms Callejas.
Consequently, finding the word table written in red might be unpleasant whereas seeing it in blue might be agreeable. This emotional reaction associated with how synaesthetes perceive consistent or inconsistent stimuli is an extremely interesting subject and has been studied for the first time in this doctoral thesis.
Some of Callejas’ conclusions show that these emotional reactions occur automatically and can not be ignored. Moreover, they can affect the synaesthete to the point of slanting his or her preferences when faced with certain stimuli which correspond to his or her inner experiences. Even more important is the fact that these emotions can transform how they perceive events associated with these experiences. These events may have no emotional meaning initially but they can become more or less pleasant if they take place at the same time the synaesthete finds a word in the correct or incorrect colour.
‘Then, there are people for whom time units evoke colours – explains the researcher. It is also common for a synaesthete to see colours when listening to words, sounds in general or music notes (people who can see music, for instance). There are also cases, although fewer, where people can see colours in flavours, others perceive flavours or experience touch sensations when listening to different sounds, some link flavours to touch sensations, etc.’
Researchers have noted that synaesthetes always experience the same vision, synaesthesia is permanent (a given stimulus always evokes the same colour for one person) and idiosyncratic (it is different for each person). Therefore, if for a synaesthete the word dog is red, every time he or she sees it, it will be perceived as red.
Even though synaesthesia has been known for a long time, its scientific study is relatively recent. Writings such as the Castel one, in which reference is made to previous studies about a synaesthesia case in a blind person, are found in the 18th century. The evolution of the study of this phenomenon has been spectacular – the number of researchers working on this topic is constantly increasing, as will be evident in the Conference which will take place in Granada – and, as the phase of proving that this phenomenon exists has been overcome, explains Alicia Callejas, ‘we are starting to approach questions of major theoretical importance, and to develop adequate study strategies.’
Brain Res. 2007 Jan 5;1127(1):99-107. Epub 2006 Nov 15.
Green love is ugly: emotions elicited by synesthetic grapheme-color perceptions.
Callejas A, Acosta A, Lupiáñez J.
Departamento de Psicología Experimental, Facultad de Psicología, Universidad de Granada, Campus Universitario Cartuja s/n, 18071 Granada, Spain. firstname.lastname@example.org
Synesthetes who experience grapheme-color synesthesia often report feeling uneasy when dealing with incongruently colored graphemes although no empirical data is available to confirm this phenomenon. We studied this affective reaction related to synesthetic perceptions by means of an evaluation task. We found that the perception of an incorrectly colored word affects the judgments of emotional valence. Furthermore, this effect competed with the word’s emotional valence in a categorization task thus supporting the automatic nature of this synesthetically elicited affective reaction. When manipulating word valence and word color-photism congruence, we found that responses were slower (and less accurate) for inconsistent conditions than for consistent conditions. Inconsistent conditions were defined as those where semantics and color-photism congruence did not produce a similar assessment and therefore gave rise to a negative affective reaction (i.e., positive-valence words presented in a color different from the synesthete’s photism or negative-valence words presented in the photism’s color). We therefore observed a modulation of the congruency effect (i.e., faster reaction times to congruently colored words than incongruently colored words). Although this congruence effect has been taken as an index of the true experience of synesthesia, we observed that it can be reversed when the experimental manipulations turn an incongruently colored word into a consistent stimulus. To our knowledge, this is the first report of an affective reaction elicited by the congruency between the synesthetically induced color of a word and the color in which the word is actually presented. The underlying neural mechanisms that might be involved in this phenomenon are discussed.