<p>The recordings of panels a, b and c are from different neurons. (a, b, c left panels) The LHb PA neurons generally exhibited a similar transient cessation in firing in response to the single-pulse VTA stimulation and the single-pulse SNpc stimulation. The left panel c showed an original firing recording for the LHb PA neuron's response to single-pulse stimulations of the VTA. Both the peristimulus time histograms were comprised of 100 consecutive sweeps. Each single stimulus pulse was delivered 100 ms after the onset of each sweep (bin: 1 ms; a, b left panels). (a, b, c right panels) PA neuron firing was increased by the tetanic VTA stimulus and the tetanic SNpc stimulus. The right panel c showed an original firing recording for the LHb PA neuron's response to the tetanic VTA stimulus. Both histograms displayed using a bin of 5 s (a, b right panels). (d) an original firing recording for the LHb PA neuron's response to tail pinch.</p
