(CORDIS) — European researchers have made a major advance in thermal imaging techniques that is bringing to life an old fable. Everyone is familiar with the children’s story of Pinocchio, a wooden puppet, with a nose that grew every time he told a lie. Now researchers from Spain are seeing parts of this tale ring true.
The researchers from the University of Granada, Department of Experimental Psychology have discovered that when a person lies he or she experiences what they have termed a ‘Pinocchio effect’. During the Pinocchio effect the subject may experience an increase in the temperature around their nose and in the orbital muscle in the inner corner of their eyes. In addition to this, the researchers discovered that when people perform a considerable mental effort, temperature around the face drops, and when we have an anxiety attack our face temperature rises. These are some of the conclusions that were arrived at in their pioneering study and as a result of their new applications in the field of thermography.
Thermography first developed in the United States during World War II to detect the enemy, is a technique based on body temperature that has been applied in many and wide ranging fields from the building industry to medicine. Thermographic cameras are already in use measuring energy loss in buildings, and indicating respiratory diseases in bovine animals or rabies in raccoons.
Emilio Gómez Milán and Elvira Salazar López from the University of Granada have pioneered the application of thermography in the field of psychology, and they have obtained very innovative and interesting results.
Temperature changes also occur in the face when a mental effort is made such as performing difficult tasks, being interrogated on a specific event or lying.
The researchers discovered that when we lie about our feelings, the temperature around our nose rises and a brain element called ‘insula’ is activated. The insula is a component of the brain reward system, and it only activates when we experience real feelings (called ‘qualias’). The insula is involved in the detection and regulation of body temperature. Therefore, there is a strong negative correlation between insula activity and temperature increase: the more active the insulae (the greater the feeling) the lower the temperature change, and vice versa, the researchers state.
The researchers have also demonstrated that temperature asymmetries on both sides of the body and local temperature changes are associated with the physical, mental and emotional status of the subject. The thermogram is a somatic marker of subjective or mental states and allows us to see what a person is feeling or thinking, professor Salazar states.
Sexual excitement and desire can also be identified in both men and women using thermography, since they induce an increase in chest and genital temperatures. This study demonstrated that – in physiological terms – men and women get excited at the same time, even though women may say they are not excited or only slightly excited.
Finally, thermography is useful for evaluating emotions (since the face thermal pattern is different) and identifying emotional contagion. For example, when a highly empathic person sees another person having an electric discharge in their forearm, they are affected by their suffering and temperature in their own forearm increases. In patients with certain neurological disease such as multiple sclerosis, the body does not properly regulate temperature, which can be detected by a thermogram. Thermography can also be applied to determine body fat patterns, which is very useful in weight loss and training programmes. It can also be applied to assess body temperature in coeliac patients and in patients with anorexia, and so on.