title: There is more to the picture than meets the rat: a study on rodent geometric shape and proportion preferences.
abstract: In rodents, the novel object preference test has been used as a behavioral parameter for evaluation of neotic exploratory behavior, and also for memory consolidation tasks. Geometric patterns of this preference are poorly understood, and may vary among species. We evaluated in Wistar rats (Rattus norvergicus) a possible exploration preference considering aluminum tripartite rounded and cylindrical objects of different proportions: 1.2; 1.618; 1.8. At the first day, animals were exposed to 1.2; 1.6 and 1.8 rounded objects. At 24h after, these animals were exposed to the same objects, together with three new steel cylindrical objects (same proportions). ANOVA and T tests were used to quantify object exploration for each animal (p<0.05). Data analysis pointed to a longer exploration time of the object 1.2 at the three different protocols indicating a preference pattern on the first day exposition. On the second day the exploration was similar in both familiar and unfamiliar objects, revealing no novel object preference for cylinders. However, we found an object preference related to the 1.2 proportion (balls plus cylinders), in two of three position protocols. In addition, on a single exposition with both cylinders and rounded objects, rats revealed a rounded object preference. The 1.2 preference disclosed by rats also reflected the proportion of their body. From nine main measures of body ratios, seven were close to 1.2 ratio. The correspondence between body ratios and object preference may be explained by habituation learning and by sexual selection, and highlight innate factors regarding aesthetic preferences among species.
authors.affiliation: Science and Technology School, Universidade Federal do Rio Grande do Norte, Brazil; International Institute of Neuroscience of Natal- Edmond &Lily Safra, Brazil.
authors.forename: Jéssica
authors.initials: J
authors.lastname: Winne
authors.affiliation: Biophysics and Pharmacology Department, Universidade Federal do Rio Grande do Norte, Brazil.
authors.forename: Leslie
authors.initials: L
authors.lastname: Teixeira
authors.affiliation: Biophysics and Pharmacology Department, Universidade Federal do Rio Grande do Norte, Brazil.
authors.forename: Jéssica
authors.initials: J
authors.lastname: de Andrade Pessoa
authors.affiliation: Biophysics and Pharmacology Department, Universidade Federal do Rio Grande do Norte, Brazil.
authors.forename: Elaine Cristina
authors.initials: EC
authors.lastname: Gavioli
authors.affiliation: Biophysics and Pharmacology Department, Universidade Federal do Rio Grande do Norte, Brazil.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Soares-Rachetti
authors.affiliation: Pharmacology Department, Universidade Federal do Paraná, Brazil.
authors.forename: Eunice
authors.initials: E
authors.lastname: André
authors.affiliation: Biophysics and Pharmacology Department, Universidade Federal do Rio Grande do Norte, Brazil. Electronic address: brunolobaosoares@gmail.com.
authors.forename: Bruno
authors.initials: B
authors.lastname: Lobão-Soares
mesh_terms: D000818:Animals; D004954:Esthetics; D005106:Exploratory Behavior; D008297:Male; D010812:Physical Stimulation; D017208:Rats, Wistar / Q000523:psychology*; D013028:Space Perception; D013037:Spatial Behavior
keywords: Golden ratio; Memory consolidation; Neuroesthetics; Novelty preference test; Object preference; Rats