Beholders' sensorimotor engagement enhances aesthetic rating of pictorial facial expressions of pain

The present study addresses a novel issue by investigating whether beholders' sensorimotor engagement with the emotional content of works of art contributes to the formation of their objective aesthetic judgment of beauty. To this purpose, participants' sensorimotor engagement was modulated by asking them to overtly contract the Corrugator Supercilii facial muscles or to refrain from any voluntary facial movement while judging the aesthetic value of painful and neutral facial expressions in select examples of Renaissance and Baroque paintings. Results demonstrated a specific increase in the aesthetic rating of paintings showing painful facial expressions during the congruent activation of the Corrugator Supercilii muscles. Furthermore, participants' empathetic traits and expertise in art were found to correlate directly with the amplitude of the motor enactment effect on aesthetic judgments. For the first time, we show the role of bottom-up bodily driven sensorimotor processes in the objective aesthetic evaluation of works of art.

Biological activities of melanotropic peptide fatty acid conjugates

Four fatty acids (FA, palmitic, myristic, decanoic, hexanoic) were individually conjugated to the N-terminus of the alpha-MSH fragment analog, H-Asp5-His6-D-Phe7-Arg8-Trp9-Lys10-NH2. This resulted in enhanced potency of the conjugates (compared to the unconjugated melanotropin analog) as determined in the lizard skin bioassay and in the mouse melanoma cell tyrosinase bioassay. The shorter conjugates of hexanoic and decanoic acid were at least equipotent to alpha-MSH in the lizard skin bioassay, whereas the longer myristoyl and palmitoyl analogs were 100 times less active. The myristoyl and palmitoyl conjugates exhibited a "creeping" potency in the lizard skin bioassay-that is, potency of the peptides increased with time in contact with the skins. These observations may be related to the more lipid nature of these FA-conjugates. In the tyrosinase assay, the conjugates were 10-100 times more active than alpha-MSH or the unconjugated analog. Each of the FA-melanotropic peptide conjugates exhibited prolonged (residual) melanotropic activity in both the lizard skin and melanoma cell bioassays. In other words, after removal of the melanotropin conjugates from contact with the skins or cells, responses were still manifested for hours or days thereafter. As little as 1 hr of contact with melanoma cells resulted in enhanced enzyme activity as measured 48 hr later. Since the conjugates, but not H-[Asp5, D-Phe7, Lys10]alpha-MSH5-10-NH2, exhibited prolonged activity, the conversion of reversible agonists to irreversible agonists was demonstrated.