Focus on females: a less biased approach for studying strategies and mechanisms of memory
Section snippets
Studying sex differences in memory
There are two interrelated approaches that dominate the study of sex differences in memory: Firstly, selection of memory tasks that show clear sex differences in performance, and comparing the strategies, circuits and molecular mechanisms engaged by each sex. Secondly, identifying neural circuits and molecular mechanisms well known for their role in memory in males and examining the role of these mechanisms in females.
Identification of behavioral and cognitive strategies used by females (and males) in memory tasks
It is becoming apparent that behavioral and cognitive strategies preferentially engaged during memory tasks differ between the sexes. In addition to the well-known sex differences in spatial strategies [40••, 41], recent work has highlighted that females and males differ in how they solve a variety of tasks [17••, 26••, 42••], suggesting that what information is learned and retrieved, and the behavioral response to fear-associated memory is not identical. To understand sex differences in
Conclusion
Given sex differences in susceptibility to memory-related disorders including posttraumatic stress disorder, Alzheimer's Disease and other dementias, understanding how both females and males learn, store, and retrieve memories is critical for developing novel treatments, preventive strategies, and identifying at-risk individuals. However, with the influx of new data on females and memory, in part as a consequence of NIH Sex as a Biological Variable initiative, it is clear a simple comparison of
Conflict of interest statement
Nothing declared.
References and recommended reading
Papers of particular interest, published within the period of review, have been highlighted as:
• of special interest
•• of outstanding interest
Acknowledgements
Many thanks to AA Keiser for her helpful discussions of content and comments on the manuscript.
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2019, Trends in NeurosciencesCitation Excerpt :Building on these foundations, ongoing research often focuses on behaviors and mechanisms that were previously defined, resulting in a perpetuating bias towards understanding ‘memory in males’. Another point to consider is that, although this approach has identified several male-specific molecular mechanisms (described in detail below), no female-specific processes have been so far identified, even in studies that include both males and females, likely owing to the under-representation of females in memory studies in general [28] (Figure 1; red text represents proteins that are differentially activated or required for memory only in males). In this review we discuss sex differences in memory in the context of emerging data on sex differences in brain and behavior, and the importance of considering sex differences across the lifespan.
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2019, Neuroscience and Biobehavioral ReviewsCitation Excerpt :However, just some of these mechanisms are known for FE or FE recall. Also, the molecular signatures of FE in each sex may reflect the engagement of specific cognitive and behavioral strategies used to approach and learn from threats (Mizuno and Giese, 2010; Shansky, 2018; Silva et al., 2013; Tronson, 2018). Researchers have pointed out, that females are more likely to engage in active responses, like darting in rats or the tend-and-befriend response in humans (Gruene et al., 2015a, 2015b; Olff, 2017; Taylor et al., 2000).