NOS1 and Anxiety: Having established that the activation of nNOS-expressing neurons in the vmPFC and the excitation of pPVT-vmPFC projections are both required for anxiety-like behaviors induced by chronic pain, but only the latter is implicated in hyperalgesia, we hypothesized that nNOS-expressing neurons in the vmPFC are stimulated by pPVT inputs and then transform the signal from pain to anxiety.