Fig. 5

Schematic of suggested mechanism of increased perforated synapse density. a Wildtype mice have silent synapses which are remodeled into non-perforated and perforated synapses. b Shank3 heterozygous mice have an increase in perforated synapses, which may not be remodeled into non-perforated synapses due to impaired LTP maintenance. c Shank3 homozygous mice have impairments in LTP induction and maintenance, which may be why the increase in perforated synapses, which is thought to be compensatory, does not occur. Black synapses indicate non-perforated synapses; gray synapses indicate silent synapses; black synapses with perforations indicate perforated synapses. Red arrows indicate mechanisms that are impaired