The following two articles model how failures of adaptively timed learning and incentive motivational support by hippocampus (i.e., failure of “time cells”) can cause clinical problems in memory consolidation and Fragile X syndrome: ***************** Franklin, D. J., and Grossberg, S. (2017). A neural model of normal and abnormal learning and memory consolidation: Adaptively timed conditioning, hippocampus, amnesia, neurotrophins, and consciousness. Cognitive, Affective, and Behavioral Neuroscience, 17, 24-76. http://link.springer.com/article/10.3758/s13415-016-0463-y This article explains and simulates the kinds of data that many cognitive neuroscientists have reported after the famous case of the amnesic patient HM; namely, how, after some learning occurs, early vs. late lesions of amygdala, hippocampus, or orbitofrontal cortex can cause very different memory consolidation problems. ***************** Grossberg, S., and Kishnan, D. (2018). Neural dynamics of autistic repetitive behaviors and Fragile X syndrome: Basal ganglia movement gating and mGluR-modulated adaptively timed learning. Frontiers in Psychology, Psychopathology. https://doi.org/10.3389/fpsyg.2018.00269. This article explains how Fragile X syndrome can be caused when mGluR-mediated adaptively timed hippocampal learning and support of motivated attention fail.