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The two papers for this week, Han et al.(2009) and Yiu et al. (2014), delve into the concept of a subpopulation of neurons in the lateral amygdala (LA) that have increased cyclic adenosine monophosphate response element-binding protein (CREB) are preferentially activated by fear memory expression and enhance fear memory formation. I found the papers effective in analyzing fear memories, but the paper go back and forth between saying memories and fear memories. I found the use of just memories misleading and not a claim either paper can support based on the methods and analyses performed.
Han et al. (2009) sets up a foundation for the research conducted in Yiu et al. (2014). Han’s approach to fear memories was straight forward. I would have like if they had used more than one fear conditioning technique because although foot shock is widely accepted, it is difficult to measure fear response based solely on freezing. Same for Yiu et. al; this paper also only uses freezing as an indicator of a fear memory. However, Yiu et al does a more thorough paradigm, with both weak training and strong training, making me inclined to believe this research.
Discussing the methods leads me into the biggest flaw of I found in this paper. This is the use of memories vs. fear memories. Both papers use fear conditioning and can therefore support an argument with fear memories but these papers don’t address other contexts of memories and cannot make a larger, more general claim that neurons in the LA that have increased CREB are preferentially activated by memory expression and enhance memory formation. They could make this claim if they associated the introduce other tasks such as a novel object recognition task or with a rewarding stimulus instead a fear-inducing stimulus. I think that the wording of these papers is their downfall and it would have been a stronger argument if they stuck with the words fear memory.

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