Table 3. Mauer's three lines of evidence for neonatal synesthesia.

Line of reasoning	Explanation	Criticism
Anatomical	Evidence of plasticity in the neonatal brain – may underlie synesthesia.	Demonstrates that the neonate brain may be more susceptible to crossmodal cortical connections, but not that this causes synesthesia.
Recording	Sensory percepts of one modality are enhanced by those of other modalities.	This is very difficult to demonstrate anything other than cross modal perception rather than synesthesia.
Behavioral	Behavioral evidence suggesting neonates can compare sensory information across modality.	Again the studies cited by Mauer cannot demonstrate neonatal synesthesia.