Ontogenetic analysis of behavior in the tail suspension test: Temporal differences in the emergence of within‐ and between‐session habituation in Swiss mice

Abstract

Habituation is an important tool in the investigation of learning/memory throughout life. Despite that, few studies describe habituation from an ontogenetic perspective. Considering that, as soon as they are born, rodents can twist their bodies when lifted by their tails in an attempt to escape, this behavior should be well suited to study habituation behavior from birth to adulthood. Here, we implement a tail suspension test to study the ontogenetic development of habituation in Swiss mice. Our data indicate that a continuous within-session decrease in trunk movements can be observed from postnatal day (P) 10 onwards and that between-sessions habituation (from one day to another) can be observed from P16 onwards. Furthermore, we show that the adult pattern of within- and between-sessions reductions in activity is already present by the beginning of adolescence, at P28. Our results indicate that between-sessions habituation involves a more complex mechanism of memory and learning than within-session habituation, requiring a longer period of brain maturation before it can be displayed.

Ethanol exposure during the brain growth spurt impairs habituation and promotes locomotor hyperactivity of infant mice in the tail suspension test.

“…Animals remained at least 10 min in the room prior to testing. The testing equipment is described in detail elsewhere (Manhães et al, 2014), therefore only a brief description will be provided here. Animals were initially attached by the tails (using surgical adhesive tape) to a metallic rod (30 cm length × 0.8 cm diameter).…”

“…In the TST, animals perform movements of the trunk while trying to escape from a clamp that holds them hanging by their tails, with no support being provided by the paws (Steru et al, 1985). Previous studies have shown that, due to its simple sensorimotor requirements, the TST can be used to test animals from just after birth up to adulthood (Manhães et al, 2014; Takahashi, Niimi, & Itakura, 2010). A particular aspect of the TST that allows for the comparison between ages is the fact that, irrespective of the animal’s age, its behavior is motivated by an attempt to escape from a distressing and uncomfortable situation (Popova & Tibeikina, 2010; Steru et al, 1985).…”

“…Recently, the TST was used to study the ontogeny of habituation in mice (Manhães et al, 2014). Habituation, a phenomenon that involves both associative and nonassociative learning mechanisms, is generally characterized by a reduction in the degree of activity presented by an individual as it becomes familiar with a situation or an environment (Kenzer, Ghezzi, & Fuller, 2013; Leussis & Bolivar, 2006).…”

“…Experimentally, the reduction in activity is observed as the test progresses (within-sessions habituation) and/or upon repeated testing (between-sessions habituation; Schmidt, Filgueiras, & Krahe, 1998; Thiel, Müller, Huston, & Schwarting, 1999). In this regard, Manhães and collaborators (2014) described a continuous within-session decrease in trunk movements from postnatal day (PN) 10 onward and a between-sessions habituation from PN16 onward (Manhães et al, 2014). Moreover, an adult pattern of within- and between-sessions reductions in activity was already present by the beginning of adolescence, at PN28 (Manhães et al, 2014).…”

“…In this regard, Manhães and collaborators (2014) described a continuous within-session decrease in trunk movements from postnatal day (PN) 10 onward and a between-sessions habituation from PN16 onward (Manhães et al, 2014). Moreover, an adult pattern of within- and between-sessions reductions in activity was already present by the beginning of adolescence, at PN28 (Manhães et al, 2014).…”