Patterns of autobiographical memory loss in dementia.

BACKGROUND

Several studies have found impaired recall of remote autobiographical memories relative to recent memories in semantic dementia (SD), a pattern opposite to that in Alzheimer's disease (AD).

OBJECTIVE

To document dissociation of memory for autobiographical incidents and personal semantic information in individuals with AD, frontotemporal dementia (FTD), and SD.

METHODS

The authors administered the Autobiographical Memory Interview to eight individuals with AD, 11 with FTD, eight with SD, and eight normal controls . Autobiographical incidents and personal semantic memory was assessed from three time periods: childhood, early adulthood, and recent life.

RESULTS

Individuals with SD recalled more details of autobiographical incidents from the most recent 5 years than from childhood and early adulthood (childhood vs recent life: t(7) = -3.59, p = 0.009; early adulthood vs recent life: t(7) = -4.33, p = 0.003). No difference was found between childhood and early adulthood (t(7) = 1.11, p = 0.305). Recall of personal semantic information was related to the age of the memory with less remembered from earlier time periods (childhood vs recent life: t(7) = -6.52, p < 0.001; childhood vs early adulthood: t(7) = -2.61, p = 0.035; early adulthood vs recent life: t(7) = -9.15, p < 0.001).

CONCLUSIONS

SD is a compelling model in which to study the anatomy of episodic memory.