COGNITIVE NEUROSCIENCE OF MEMORY.

One of the titles in the Cambridge Fundamentals of Neuroscience in Psychology series, this is a review of memory research, specifically in terms of cognitive neuroscience. The author, Dr Scott Slotnick, claims in the preface that this is “the first book to provide a comprehensive treatment of the cognitive neuroscience of memory.” He further states that “this book provides a complete overview of the cognitive neuroscience of memory and aims to guide the future of memory research.” These ambitious and somewhat selfcongratulatory statements initially put me on guard to be critical, but by the end of the considerable time I spent reading the book, I felt that they were justified, at least in terms of my own reading history. Slotnick does provide several suggestions for future research at several points in the book. I have no doubt that young memory researchers can derive a wealth of projects from the book, though perhaps the claim that it will guide the future of memory research seems a bit overambitious. I did have a few issues with the writing style. In Chapter 1, the author refers to 2 centuries of history and then cites Aristotle, who wrote considerably longer ago than that (>2 millenia). I also found the singular and plural pronouns disconcerting; for example, “a person …. They.” I am not sure if Slotnick is using the gender-neutral pronoun plural “they” to protect genders, or if he is just inattentive to grammar. Clinical neurologists will also need to adopt some terminology from basic memory research. In this book, for example, short-term memory is equivalent to working memory or attention span, and long-term memory encompasses tasks such as remembering three words for 5 minutes, which clinicians would consider shortterm memory. Chapter 2 encompasses methods in memory research, including not only behavioral techniques, but also fMRI and evoked-response methodologies. These are indeed tools that future memory researchers will need to master, but they are not used in routine clinical practice by clinical neurologists. Chapter 3 discusses brain regions associated with memory. Most of this material is a good review for cognitive neurologists. If I learned one key concept from this book, it would be that, in terms of anatomy, the perirhinal cortex is associated with item memory, the parahippocampal cortex is associated with context memory, and the hippocampus itself is involved with binding item information with context information to form memories. This important anatomic evidence is presented here and also later in the book, in a chapter about animal memory. Chapter 3 also contains an interesting discussion of superior memory, such as the ability of London taxi drivers to recall 25,000 city streets and the locations of thousands of urban attractions. In MRI studies, these individuals had enlarged posterior hippocampal gray matter and reduced anterior hippocampal gray matter. It seems that individuals with superior memory can achieve enlargement of some gray structures at the expense of others, and that their superior ability for one type of memory may be associated with normal general intelligence and with reduced memory ability for another class or type of memory. Chapters 4 and 5 discuss brain timing and activity as well as normal forgetting. The discussion of forgetting refers to the default network, that series of brain regions that are active when an individual is just lying quietly, not involved in any specific cognitive task. However, the discussion does not spell out the specific brain regions involved in the default network. Chapter 5 also contains an interesting discussion of false memories, including the fact that they activate the same structures as true memories, including the dorsolateral prefrontal cortex, parietal cortex, hippocampus, and some visual structures. The false memories were associated with increased activation of the superior posterior temporal cortex. The author suggests that this area of the brain is involved in language, such that individuals may attach verbal labels to the new stimuli that help them remember these stimuli, but then the verbal label may be erroneously attached to a false-memory stimulus. False memories, of course, are highly important in legal and criminal cases. Another concept discussed in this chapter is “flashbulb memories,” memories that are attached to dramatic historic events such as the Kennedy assassination or the space shuttle disaster. According to Slotnick, these memories are mediated by the dorsolateral frontal lobe. Chapter 6 involves working memory—what clinicians often call immediate memory. This function does not involve the hippocampus, as clinicians know by its preservation in patients with acquired amnesia and its deficiency in patients with aphasia and frontal lobe lesions. Chapter 7, on implicit memory, discusses the localization of this form of memory. Again, it does not involve the hippocampi; rather, it involves the dorsolateral frontal lobes and the sensory processing areas of the brain. Chapter 8 discusses the relationship of memory to attention, language, emotion, and other functions. A wealth of experimental metholology and data fills this chapter. Chapter 9 is the most clinical chapter of the book, focusing on explicit memory and disease processes. This is territory that is very familiar to clinical neurologists. Amnestic mild cognitive impairment, memory in traumatic brain injury, Alzheimer disease, and memory in epilepsy are some of the topics discussed in this chapter. Aside from consideration of several experimental paradigms for research in these conditions, the discussion is largely a rehash of clinical The reviewer declares no conflicts of interest.