="an ">&ensp;</span>dopamine <span  title="" class="an ">&ensp;</span>release <span  title="" class="an ">&ensp;</span>and <span  title="" class="an ">&ensp;</span>pain <span  title="" class="an ">&ensp;</span>plasticity <span  title="" class="an ">&ensp;</span>However <span  title="" class="an ">&ensp;</span>the <span  title="" class="an ">&ensp;</span>unitary <span  title="" class="an ">&ensp;</span>conductance <span  title="" class="an ">&ensp;</span>gamma <span  title="" class="an ">&ensp;</span>of <spa