Rewarding effects of the electrical stimulation of the parabrachial complex: Taste or place preference?

• Electrical stimulation of parabrachial complex induces place and taste preferences.
• This study examined the relative relevance of taste and place stimuli.
• A learning task was used that simultaneously included both flavor and place stimuli.
• After learning, a reversal test showed preference for the place stimuli.
• These results are related to the learning bias of other rewarding agents.

The lateral parabrachial complex has been related to various emotional-affective processes. It has been shown that electrical stimulation of the external Lateral Parabrachial (LPBe) nucleus can induce reinforcing effects in place preference and taste discrimination tasks but does not appear to support self-stimulation. This study examined the relative relevance of place and taste stimuli after electrical stimulation of the LPBe nucleus. A learning discrimination task was conducted that simultaneously included both sensory indexes (taste and place) in order to determine the preference of animals for one or the other. After a taste stimulus reversal task, the rewarding effect of stimulation was found to be preferentially associated with place. These results are discussed in the context of the rewarding action and biological constraints induced by different natural and artificial reinforcing agents.