Focus on females: a less biased approach for studying strategies and mechanisms of memory

https://doi.org/10.1016/j.cobeha.2018.04.005Get rights and content

Highlights

  • Direct comparisons between sexes fail to detect female-specific memory mechanisms.

  • Females and males differ in behavioral and cognitive strategies in memory tasks.

  • Appropriate behavioral measures are key for studying what females are learning.

  • Exploratory approaches are necessary to identify female-specific memory mechanisms.

  • A female-focused approach is necessary for novel insights into learning and memory.

Recent work on sex differences in learning and memory has demonstrated that females and males differ in cognitive and behavioral strategies, as well as neural mechanisms required to learn, retrieve, and express memory. Although our understanding of the mechanisms of memory is highly sophisticated, this work is based on male animals. As such, the study of female memory is narrowed to a comparison with behavior and mechanisms defined in males, resulting in findings of male-specific mechanisms but little understanding of how females learn and store information. In this paper, we discuss a female-focused framework and experimental approaches to deepen our understanding of the strategies and neural mechanisms engaged by females (and males) in learning, consolidation, and retrieval 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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