, 2009), and with subjective ratings of appetite during the prese

, 2009), and with subjective ratings of appetite during the presentation of food-related stimuli in healthy young individuals (Porubská et al., 2006). In contrast to these studies, we used the questionnaire of PFS which was designed to examine directly individual differences in the appetitive motives UK-371804 ic50 in the face of incentive of food (food available, present or tasted) in daily life. In our recent report, significant correlations were observed in

the Fasting condition between the intensities of the MEG responses and the aggregated scores and the subscale scores of factor-1 (food available) and those of factor-2 (food present) of PFS (Yoshikawa et al., 2013). The correlations were replicated in the present study. Combined with the results, while the intensities of magnetic responses of insular cortex in the Fasting condition were correlated with self-awareness of appetitive motives when food is available or present before tasting, those in the ‘Hara-Hachibu’ condition were more correlated with the self-awareness of motives after tasting. The findings are plausible in the view of one-to-one correspondence between p38 MAPK inhibitor dietary condition (Fasting or ‘Hara-Hachibu’) and the setting of PFS (before or after tasted). In other words, the insular cortex in some individuals might tend to be more reactive to information about food cues before eating, and the brain area in others might

be susceptible to the visual stimuli of food even after they have eaten (in the ‘Hara-Hachibu’ condition). Such tendencies of acute activity in insular cortex might lead to self-awareness of their appetitive motives in daily dietary life. It is thought that the sensitivity of the insular cortex to visual food stimuli might be genetically inherited or acquired (learned)

later in life. Previous animal studies showed that the gustatory insular cortex is involved in encoding changes in the incentive value assigned to instrumental outcomes on the basis of prevailing Histamine H2 receptor motivational conditions (Balleine and Dickinson, 2000), supporting the latter acquired (conditioned) theory. Accordingly, conditioning is one of the possible mechanisms of the observed association of insular cortex activity with subscale scores of factor-3 of PFS in the ‘Hara-Hachibu’ condition as well as the factors-1 and 2 of PFS in the Fasting condition. It is interesting to speculate as to whether and how the conditioning-related sensitivity of the insular cortex to visual food stimuli can be altered by life-style changes such as overfeeding (Cornier et al., 2009) and exercise (Cornier et al., 2012 and Evero et al., 2012). Future investigation will be needed to elucidate the mechanism whereby the conditioned instantaneous responses of insular cortex can be altered. The present study has several potential limitations. Firstly, we examined the brain activity in normal-weight young males without apparent eating disorders.

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