levels. Assessment of the mother using the ADHD Self-Report Scale indicated a likelihood of ADHD (scores of 20 for part A and 12 for part B).46 The mother, and to a lesser extent, all three children, display problems with spatial orientation, a characteristic also observed in the GRM5 null mouse.47 Intriguingly, GRM5 null mice also have deficiencies in long-term potentiation47 as well as an increase in anxiety-like behavior that can be reduced with GRM5 antagonists.48 ADHD frequently occurs in Fragile X syndrome,49 and GRM5 antagonists have recently been shown to de-repress startle inhibition in Fragile X (FMR1) null mice.
