Identification of emotions and physiological response in individuals with moderate intellectual disability.

According to Ekman's model, the basic emotions are anger, disgust, fear, happiness, sadness, and surprise. These emotions are universal and have an adaptative function. However, studies on these emotions among individuals with moderate intellectual disability (MID) are limited, mainly owing to issues in sample size and sample homogeneity. The present study aimed to explore differences between a MID group ( n =  10) and a non-MID control group ( n =  10) in 1) the identification of basic emotions; and 2) the physiological response with images related to fear, happiness, sadness, anger, and disgust, as well as images with neutral and sexual content. A total of 29 images from The International Affective Picture System and a biofeedback measurement system were used. The results showed no statistically significant differences in the identification of the basic emotions of fear, sadness, and disgust. However, statistically significant differences were found for happiness ( p = .008), anger ( p = .02), and neutral images ( p = .02), and minor statistically significant differences were found for images with sexual content ( p < .01) in MID individuals with respect to the control group. The MID group's physiological response was lower compared with the control group, with statistically significant differences for all emotional visual stimuli. This preliminary study showed important and interesting results for the study of emotions and sexuality in MID. Future studies should consider the sample size, sex and age comparisons, and the different levels of intellectual disability.