A MoCA cutoff score of 23, rather than the initially recommended score of 26, lowers the false positive rate and shows overall better diagnostic accuracy. We recommend the use of this cutoff score going forward. Copyright © 2017 John Wiley & Sons, Ltd.

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A current debate in the literature is whether all declarative memories and associated memory processes rely on the same neural substrate. Here, we show that H.C., a developmental amnesic person with selective bilateral hippocampal volume loss, has a mild deficit in personal episodic memory, and a more pronounced deficit in public event memory; semantic memory for personal and general knowledge was unimpaired. This was accompanied by a subtle difference in impairment between recollection and familiarity on lab-based tests of recognition memory. Strikingly, H.C.'s recognition did not benefit from a levels-of-processing manipulation. Thus, not all types of declarative memory and related processes can exist independently of the hippocampus even if it is damaged early in life.

Difficulties remembering one’s own experiences via episodic memory may affect the ability to imagine other people’s experiences during theory of mind (ToM). Previous work shows that the same set of brain regions recruited during tests of episodic memory and future imagining are also engaged during standard laboratory tests of ToM. However, hippocampal amnesic patients who show deficits in past and future thinking, show intact performance on ToM tests, which involve unknown people or fictional characters. Here we present data from a developmental amnesic person (H.C.) and a group of demographically matched controls, who were tested on a naturalistic test of ToM that involved describing other people’s experiences in response to photos of personally familiar others (“pToM” condition) and unfamiliar others (“ToM” condition). We also included a condition that involved recollecting past experiences in response to personal photos (“EM” condition). Narratives were scored using an adapted Autobiographical Interview scoring procedure. Due to the visually rich stimuli, internal details were further classified as either descriptive (i.e., details that describe the visual content of the photo) or elaborative (i.e., details that go beyond what is visually depicted in the photo). Relative to controls, H.C. generated significantly fewer elaborative details in response to the pToM and EM photos and an equivalent number of elaborative details in response to the ToM photos. These data converge with previous neuroimaging results showing that the brain regions underlying pToM and episodic memory overlap to a greater extent than those supporting ToM. Taken together, these results suggest that detailed episodic representations supported by the hippocampus may be pivotal for imagining the experiences of personally familiar, but not unfamiliar, others.