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This chapter discusses human functional neuroimaging findings about how the brain creates true and false memories. These studies have shown that different brain systems contribute to the creation and retrieval of false memories, including systems for sensory perception, executive functioning and cognitive control, and the medial temporal lobe, which has long been associated with episodic and autobiographical memory formation. Many neuroimaging findings provide support for an associative account of false memories, which proposes that false memories arise from associating unrelated mental experiences in memory. At the same time, other neuroimaging findings suggest that false memory creation may depend on states of brain activity during memory encoding. Finally, the chapter briefly provides cautionary notes about using functional neuroimaging as a tool to assess private mental states in individual cases in the courtroom.

Mild cognitive impairment (MCI), which shows high risk for conversion to Alzheimer's disease (AD), is accompanied by progressive visual deteriorations that so far are poorly understood. Here, we compared dorsal and ventral visual stream functional magnetic resonance imaging (fMRI) activity among amnestic MCI, healthy elderly, and young participants during structure-from-motion (SFM) face categorization performance. Task performance varied with stimulus depth and duration levels and differences among groups were highly correlated with face-related fMRI activation patterns. Young participants showed larger activation to faces than scrambled faces (face sensitivity) in the right fusiform face area (FFA) and right occipital face area (OFA) whereas in elderly, this difference was reduced. Surprisingly, in MCI, scrambled faces elicited larger activation in right FFA/OFA than faces. The latter observation may be related to the additional finding of elevated depth sensitivity in left FFA/OFA of MCI, suggesting that an increased representation of low-level stimulus aspects may impair face perception in MCI. Discriminant function analysis using face and depth sensitivity indices in FFA/OFA classified MCI and healthy elderly with 88.2% accuracy, marking a fundamental distinction between groups. Potentially related findings include altered activation patterns in dorsal-ventral stream integration regions and attention-related networks of MCI patients. Our results highlight aberrant visual and additional potentially compensatory processes that identify dispositions of (preclinical) AD.