In C. elegans, this is characterized by the failure to move towards typically attractive volatile organic molecules sensed by the AWA compared to control.
Movement towards typically attractive volatile organic chemicals is altered as defined by control animals. In C. elegans, these odorants are typically sensed by the AWA and AWC neurons.
Any variation in the directed movement of an animal in response to a volatile chemical stimulus that is usually received and processed by the AWA sensory neuron in control animals.