val1 flies have attenuated baseline brain responses when exposed to visual objects alone, compared to wild type flies. Mutant flies also exhibit an aberrant response to novel objects.
Homozygous val1 mutants do not show any increased sensitivity to ethanol vapor compared with controls. However val1 mutant flies do show reduced tolerance to ethanol. Whereas control flies exhibit a reduced behavioural response following pre-exposure to ethanol in comparison with humidified air, val1 mutant flies exposed to either ethanol or air produce a similar response.
In memory tests, mutants perform at 101% of wild-type after a single training session, at 57% after spaced training.