Chronic overeating can lead to weight gain and obesity. Sensory system function may play a role in the types
of foods people select and the amount of food people eat. Several studies have shown that the orosensory
components of eating play a strong role in driving food intake and food selection. In addition, previous
work has shown that motivation to get food, or the reinforcing value of food, is a predictor of energy intake.
The purpose of this study was to test the hypothesis that higher detection thresholds and lower suprathreshold
intensity ratings of sweet and fat stimuli are associated with greater reinforcing value of food. In addition,
we sought to determine if the sensory ratings of the stimuli would differ depending on whether they
were expectorated or swallowed. The reinforcing value of food was measured by having participants perform
operant responses for food on progressive ratio schedules of reinforcement. Taste detection thresholds and
suprathresholds for solutions containing varied concentrations of sucrose and fat were also measured in
two different Experiments. In Experiment 1, we found that sucrose, but not fat, detection predicted the reinforcing
value of food with the reinforcing value of food increasing as sucrose detection threshold increased
(indicating poorer detection). In Experiment 2, we found that lower suprathreshold ratings of expectorated
fat and sucrose predicted greater reinforcing value of food. In addition, higher detection thresholds for fat
stimuli (indicating poorer detection) were associated with greater reinforcing value of food. When taken together,
these studies suggest that there is a relationship between taste detection and perception and reinforcing
value of food and that these relationships vary based on whether the stimulus is swallowed or
expectorated.