“…Several studies have looked at learning grounded terms for space and time, in our own group and others, to name spatial prepositions (Steels, 1995(Steels, , 1999Roy, 2002a;Cangelosi et al, 2005), route descriptions (Levit and Roy, 2007;Tellex et al, 2011), spatial relations (Spranger et al, 2014), toponyms (Jung and Zelinsky, 2000;Schulz et al, 2011a), landmarks (Spranger, 2012(Spranger, , 2013, durations (Schulz et al, 2011b;Heath et al, 2012a) and event-based time (Steels and Baillie, 2003;Heath et al, 2012b). These studies can be divided into those that ground directly in perception (Steels, 1995(Steels, , 1999Roy, 2002a;Spranger et al, 2014) and those that ground in higher-level representations of space and time (Jung and Zelinsky, 2000;Steels and Baillie, 2003;Cangelosi et al, 2005;Levit and Roy, 2007;Schulz et al, 2011a;Tellex et al, 2011;Heath et al, 2012aHeath et al, , 2012b. The latter group are more relevant to these studies since they require intermediate representations between perception and symbols to allow agents to ground symbols in abstractions that go beyond what is directly perceptible (i.e.…”