The prelimbic cortex but not the anterior cingulate cortex plays an important role in social recognition and social investigation in mice.

The prefrontal cortex (PFC) has been implicated in social cognitive functions and emotional behaviors in rodents. Each subregion (prelimbic cortex, PL; infralimbic cortex; and anterior cingulate cortex, ACC) of the PFC appears to play a different role in social and emotional behaviors. However, previous investigations have produced inconsistent data, and few previous studies directly compared the roles of the PFC subregions using the same experimental paradigm.

Testosterone interrupts binding of Neurexin and Neuroligin that are expressed in a highly socialized rodent, Octodon degus.

Octodon degus is said to be one of the most human-like rodents because of its improved cognitive function. Focusing on its high sociality, we cloned and characterized some sociality-related genes of degus, in order to establish degus as a highly socialized animal model in molecular biology. We cloned degus Neurexin and Neuroligin as sociality-related genes, which are genetically related to autism spectrum disorder in human.

Auditory-induced visual illusions in rodents measured by spontaneous behavioural response.

When two brief sounds are presented with a short flash of light, we often perceive that the flash blinks twice. This phenomenon, called the "sound-induced flash illusion", has been investigated as an example of how humans finely integrate multisensory information, more specifically, the temporal content of perception. However, it is unclear whether nonhuman animals experience the illusion.

Effects of intraperitoneal and intracerebroventricular injections of oxytocin on social and emotional behaviors in pubertal male mice.

Oxytocin plays important roles in the social and emotional behaviors of mammals. In the present study, we examined the effects of intraperitoneal (IP) and intracerebroventricular (ICV) injections of oxytocin on these behaviors in pubertal male mice. Male C57BL/6J mice received IP injection of oxytocin (high-dose group: 1 mg/kg, low-dose group: 0.

Influence of Pre-Weaning Social Isolation on Post-Weaning Emotion Tendency and Mother-Infant Interactions in Infant .

Our previous research using (degus) revealed that preweaning social isolation negatively affected object exploratory behavior. However, it remains unknown how social isolation affects animal psychology and other behaviors. The present study examined the effects of neonatal social isolation on degu emotion and mother-infant interactions before and after weaning.

[The role of the orbitofrontal cortex in delayed reinforcement choice in rats].

Previous studies have reported that lesions of the orbitofrontal cortex (OFC) in rats induce impulsive choices in delayed reinforcement tasks. However, some studies have suggested that the OFC is not related to impulsivity but instead to compulsivity. In this study, we investigated the effects of OFC lesions on choice in a T-maze.

Hippocampus lesions induced deficits in social and spatial recognition in Octodon degus.

Previous studies of rodents reported that the hippocampus plays an important role in social behavior as well as spatial behavior. However, there are inconsistencies between reports of the effects of hippocampal lesions on social behavior. The present study sought to clarify the aspects of social behavior in which the hippocampus plays a role in the degu, Octodon degus, a social rodent.

Pretraining does not ameliorate spatial learning deficits induced by intrahippocampal infusion of AP5.

Previous studies show discrepancies concerning the effects of pretraining on spatial learning deficits induced by blockade of the N-methyl-D-aspartate (NMDA) receptor. These inconsistencies might be attributed to the differences in the nature of the pretraining tasks and the method of blocking NMDA receptors. In the present study, the authors pretrained rats in a spatial water maze task.

Dissociation of the roles of NMDA receptor and hippocampus in rats' spatial learning: the effects of environmental familiarity and task familiarity.

In this study, we compared the effects of MK-801 and hippocampal lesions on re-training of Morris water maze place task in familiar and novel environments in rats. In Experiment 1, rats were pre-trained with the place task. After acquiring the task, rats were re-trained with the same task in a familiar environment following MK-801 injection, and were then trained with the same task in a novel environment following MK-801 injection.

NMDA antagonist MK-801 does not interfere with the use of spatial representation in a familiar environment.

There is disagreement among researchers concerning whether glutamatergic N-methyl-D-aspartate (NMDA) receptors play a role in constructing spatial representations. Therefore, the authors reexamined the effects of the NMDA antagonist on a spatial discrimination task using rats in a water pool. The authors confirmed that MK-801 impaired acquisition of the spatial discrimination task (Experiment 1).

[Interactive effect of MK-801 and pre-training on spatial learning in rats].

In experiment 1, the effect of an NMDA receptor antagonist, MK-801, on the formation of the spatial representation was investigated. The administration of 0.1 mg/kg of MK-801 induced learning deficits in rats (n = 10) with the Morris watermaze task.