Appraisal process in sheep (Ovis aries): interactive effect of suddenness and unfamiliarity on cardiac and behavioral responses.
Appraisal theories state that an emotion results from an individual's evaluation of a stimulating event, which is based on a set of criteria. Each criterion triggers specific expressions that can be modulated by the outcome of other criteria. The authors analyzed the effects of the criteria of suddenness, unfamiliarity, and their combination on behavioral and cardiac responses in lambs (Ovis aries). Lambs were exposed to a visual stimulus that appeared either rapidly or slowly and was either unfamiliar or familiar. Suddenness induced a startle response and an increase in heart rate. Unfamiliarity induced an orientation response. The combination of suddenness and unfamiliarity enhanced both the heart rate increase and the behavioral orientation response. These results support the hypotheses of specificity and modulation of emotional expressions.
Désiré
Lara
L
Unite de Recherches sur les Herbivores, Institut National de la Recherche Agronomique-Clermont-Ferrand Theix, F-63122 Saint-Genes-Champanelle, France.
Veissier
Isabelle
I
Després
Gérard
G
Delval
Eric
E
Toporenko
Gilles
G
Boissy
Alain
A
D000367:Age Factors; D000818:Animals; D001143:Arousal / Q000187:drug effects; D001262:Atenolol; D001285:Atropine; D001288:Attention / Q000187:drug effects; D001340:Autonomic Nerve Block; D001364:Awareness / Q000187:drug effects; D004644:Emotions / Q000187:drug effects; D005260:Female; D006185:Habituation, Psychophysiologic; D006339:Heart Rate / Q000187:drug effects; D011939:Mental Recall / Q000187:drug effects; D009949:Orientation / Q000187:drug effects; D010364:Pattern Recognition, Visual / Q000187:drug effects; D013216:Reflex, Startle / Q000187:drug effects; D012756:Sheep / Q000523:psychology*
D001262:Atenolol; D001285:Atropine