Long-term social recognition memory in adult male rats: factor analysis of the social and non-social behaviors
Braz. j. med. biol. res
; 43(7): 663-676, July 2010. ilus, graf
Article
in English
| LILACS
| ID: lil-550732
Responsible library:
BR1.1
ABSTRACT
A modified version of the intruder-resident paradigm was used to investigate if social recognition memory lasts at least 24 h. One hundred and forty-six adult male Wistar rats were used. Independent groups of rats were exposed to an intruder for 0.083, 0.5, 2, 24, or 168 h and tested 24 h after the first encounter with the familiar or a different conspecific. Factor analysis was employed to identify associations between behaviors and treatments. Resident rats exhibited a 24-h social recognition memory, as indicated by a 3- to 5-fold decrease in social behaviors in the second encounter with the same conspecific compared to those observed for a different conspecific, when the duration of the first encounter was 2 h or longer. It was possible to distinguish between two different categories of social behaviors and their expression depended on the duration of the first encounter. Sniffing the anogenital area (49.9 percent of the social behaviors), sniffing the body (17.9 percent), sniffing the head (3 percent), and following the conspecific (3.1 percent), exhibited mostly by resident rats, characterized social investigation and revealed long-term social recognition memory. However, dominance (23.8 percent) and mild aggression (2.3 percent), exhibited by both resident and intruders, characterized social agonistic behaviors and were not affected by memory. Differently, sniffing the environment (76.8 percent of the non-social behaviors) and rearing (14.3 percent), both exhibited mostly by adult intruder rats, characterized non-social behaviors. Together, these results show that social recognition memory in rats may last at least 24 h after a 2-h or longer exposure to the conspecific.
Full text:
Available
Collection:
International databases
Database:
LILACS
Main subject:
Social Behavior
/
Recognition, Psychology
/
Agonistic Behavior
Type of study:
Prognostic study
Aspects:
Social determinants of health
Limits:
Animals
Language:
English
Journal:
Braz. j. med. biol. res
Journal subject:
Biology
/
Medicine
Year:
2010
Document type:
Article
Affiliation country:
Brazil
Institution/Affiliation country:
Universidade de São Paulo/BR