TY - JOUR
T1 - Fearfulness and sex in F2 Roman rats: Males display more fear though both sexes share the same fearfulness traits
AU - Aguilar, Raúl
AU - Gil, Luis
AU - Gray, Jeffrey A.
AU - Driscoll, Peter
AU - Flint, Jonathan
AU - Dawson, Gerard R.
AU - Giménez-Llort, Lydia
AU - Escorihuela, Rosa M.
AU - Fernández-Teruel, Alberto
AU - Tobeña, Adolf
PY - 2003/1/1
Y1 - 2003/1/1
N2 - The pattern of sex differences in a large sample (about 400 for each sex) of F2-generation rats, derived from inbred Roman high- and low-avoidance strains differing in fearfulness and brain functioning, was investigated. We obtained measures from responses to a battery of novel/threatening tests [open field (OF), plus maze (PM), hole board (HB), activity (A), and acoustic startle reflex (ASR)] as well as learned fear paradigms [classical fear conditioning (CFC) and shuttlebox avoidance conditioning (SAC)]. The results showed that almost all behaviors assessed fit with a pattern of unidirectional sex effects characterized by male rats as being more fearful than females: males defecated more than females in the OF, PM, HB, ASR, and CFC; ambulated less in the OF, PM, A, and SAC; showed more self-grooming in PM and HB; explored the open arms of the PM and the holes of the HB less; displayed enhanced ASR; and showed poorer performance in the SAC task. We applied two factor analyses to each sex showing that, in general, they shared a common three-factor structure: a Learned Fear Factor comprising SAC and CFC responding, a Fear of Heights/Open Spaces Factor with the highest loadings for open arm behavior in the PM, and an Emotional Reactivity Factor, mainly grouping defecations, ambulation, and self-grooming. These results indicate that the essential components of fearful behavior are similar for both sexes in an inbred but genetically heterogeneous population. © 2003 Elsevier Science Inc. All rights reserved.
AB - The pattern of sex differences in a large sample (about 400 for each sex) of F2-generation rats, derived from inbred Roman high- and low-avoidance strains differing in fearfulness and brain functioning, was investigated. We obtained measures from responses to a battery of novel/threatening tests [open field (OF), plus maze (PM), hole board (HB), activity (A), and acoustic startle reflex (ASR)] as well as learned fear paradigms [classical fear conditioning (CFC) and shuttlebox avoidance conditioning (SAC)]. The results showed that almost all behaviors assessed fit with a pattern of unidirectional sex effects characterized by male rats as being more fearful than females: males defecated more than females in the OF, PM, HB, ASR, and CFC; ambulated less in the OF, PM, A, and SAC; showed more self-grooming in PM and HB; explored the open arms of the PM and the holes of the HB less; displayed enhanced ASR; and showed poorer performance in the SAC task. We applied two factor analyses to each sex showing that, in general, they shared a common three-factor structure: a Learned Fear Factor comprising SAC and CFC responding, a Fear of Heights/Open Spaces Factor with the highest loadings for open arm behavior in the PM, and an Emotional Reactivity Factor, mainly grouping defecations, ambulation, and self-grooming. These results indicate that the essential components of fearful behavior are similar for both sexes in an inbred but genetically heterogeneous population. © 2003 Elsevier Science Inc. All rights reserved.
KW - Anxiety
KW - Factor analysis
KW - Fear
KW - Roman rats
KW - Sex differences
U2 - https://doi.org/10.1016/S0031-9384(03)00043-X
DO - https://doi.org/10.1016/S0031-9384(03)00043-X
M3 - Article
SN - 0031-9384
VL - 78
SP - 723
EP - 732
JO - Physiology and Behavior
JF - Physiology and Behavior
ER -