In recent years, research has progressively increased the importance of considering sex differences in stress and fear memory studies. Many studies have traditionally focused on male subjects, potentially overlooking critical differences with females. Emerging evidence suggests that males and females can exhibit distinct behavioral and neurophysiological responses to stress and fear conditioning. These differences may be attributable to variations in hormone levels, brain structure, and neural circuitry, particularly in regions such as the prefrontal cortex (PFC). In the present study, we explored sex differences in prelimbic cortex (PL) calcium activity in animals submitted to immobilization stress (IMO), fear conditioning (FC), and fear extinction (FE). While no significant sex differences were found in behavioral responses, we did observe differences in several PL calcium activity parameters. To determine whether these results were related to behaviors beyond stress and fear memory, we conducted correlation studies between the movement of the animals and PL activity during IMO and freezing behavior during FC and FE. Our findings revealed a clear correlation between PL calcium activity with movement during stress exposure and freezing behavior, with no sex differences observed in these correlations. These results suggest a significant role for the PL in movement and locomotion, in addition to its involvement in fear-related processes. The inclusion of both female and male subjects is crucial for studies like this to fully understand the role of the PFC and other brain areas in stress and fear responses. Recognizing sex differences enhances our comprehension of brain function and can lead to more personalized and effective approaches in the study and treatment of stress and fear-related conditions.
Keywords: Calcium imaging; Fear learning; Fear memory; Miniscopes; Movement; PFC; Sex differences; Stress.
In recent years, researchers have started paying more attention to the differences between males and females in how they handle stress and remember fearful events. Traditionally, many studies focused mainly on males, which might have missed important differences in females. New findings seem to suggest that males and females can respond differently to stress and fear due to differences in hormone levels, brain structure, and brain circuits, especially in the prefrontal cortex (PFC).In this study, we looked at how male and female animals’ brains reacted to being restrained, experiencing a strong trauma, and then trying to learn a new fearful memory. While their behaviors didn’t show significant differences between sexes, their brain activities did. We found that the prelimbic area of the brain shows calcium activity linked to the animals’ movements during stress and their freezing behavior during fear-related tests.These results show that the PL is involved in both movement and fear responses. Including both male and female subjects in such studies is vital to fully understand how the prefrontal cortex and other brain areas work in stress and fear situations. Recognizing these differences helps improve our understanding of brain function and can lead to better, more personalized treatments for stress and fear-related conditions.
© 2024. The Author(s).