MTO1 and Anxiety: When tested for spontaneous behavior in a novel environment in the modified Hole Board test, Mto1 mice (aged 8 weeks) of both sexes exhibited increased horizontal locomotor activity as indicated by total distance travelled, mean velocity and object exploration, as well as reduced anxiety-related behavior as measured by increased percentage of time spent on the board in the anxiogenic centre of the test arena and reduced percentage of time spent at the partition, i.e. in group contact with the cage mates (Figs. 2A–E).