How We Remember: Brain Mechanisms of Episodic Memory (Michael Hasselmo)

I love to study memory; it's my area of primary interest within cognitive psychology. For that reason, I expected to love this book, a close examination of how episodic memory works. Episodic memory is the memories of my actual life experiences, where I remember being there. For example, knowing what a toothbrush is for is a semantic memory, knowing how to brush my teeth is a procedural memory, but remembering brushing my teeth this morning, while looking out the window and observing that the sky is clear after days of rain--that is an episodic memory. I'm sad to say, however, that this book didn't work for me. Partly because this book goes deeper than my interest goes into those brain mechanisms mentioned in the title. I like to learn about different brain structures and how they work together, but kept skipping over the analyses of neural firing patterns in individual brain cells. Another problem I had is that the author explicitly defined episodic memory as the recovery of a spatiotemporal trajectory: first I went there and did that, next I went here and did this, and so on. I kept waiting for them to address the fact that some episodic memories don't have specific places and times linked to them, at least in my experience. Last week I was driving around town looking for a specific tree I had seen that I wanted to photograph. I had the location and time only very generally (somewhere within a half-hour or so of my house; somewhere in the winter, last year or perhaps the year before). I couldn't link it to anything that came before or after. But I had a clear memory of looking out the right side of the car as I rode in the passenger seat and thinking, "That's a really cool tree. I need to come back sometime and photograph it when the leaves are out." There is no trajectory in this memory, but it seems to me clearly to be an episodic memory, and this book can't account for it. While I admire and respect the work this author has done in uncovering some of the most basic aspects of episodic memory, all told it didn't click for me.