“…In developmental amnesia, semantic memory appears to be intact despite significant hippocampal agenesis and episodic memory impairment (Vargha-Khadem et al, 2001;Gadian et al, 2000;Guillery-Girard et al, 2004;Elward and Vargha-Khadem, 2018). Though developmental amnesia allows for normal knowledge of intrinsic features of concepts, it leads to abnormal semantic representations of extrinsic features of concepts (e.g., typical uses or locations of objects) (Blumenthal et al, 2017) similar to deficits described in remote semantic knowledge in adult-acquired amnesia (Waidergoren et al, 2012;Hilverman and Duff, 2021). Rapid acquisition of new knowledge has also been described in adult-acquired amnesia when it is tied to prior knowledge (Skotko et al, 2004;Ryan et al, 2013;Sharon et al, 2011;Merhav et al, 2014;Kopelman and Morton, 2015;Westmacott et al, 2004;Corkin, 2013), consistent with the notion that cortical memory traces can be formed rapidly at the time of encoding (Hebscher et al, 2019b).…”