High frequency optogenetic activation of inputs to the lateral amygdala forms distant association with foot-shock

摘要

Association between optogenetic stimulation and foot-shock. Expression of oChIEF-tdTomato in the AC and the MGN (left), as well as the LA (right) 4 weeks after viral injection. Blue arrow indicates position of implanted optic fiber. Scale bars: 500 μm. Behavioral paradigms of associative fear training (left) and recall test (right). . Fear training using oMFS paired or unpaired with foot-shocks (repeated every 3 min for 5 times). Fear response was assessed in the lever-pressing box 24 h later with OTS. Normalized number of lever presses (shown in 1-min bin) from lever-pressing tests 24 h after fear training. Lever pressing was significantly inhibited by OTS (blue area) in the paired group (  = 4) but not in the unpaired group (  = 4). * indicates  e Mean normalized number of lever presses during the 2 min of the OTS. Significant reduction in lever pressing was found in paired group (  = 4) compared with the unpaired group (  = 4). ** indicates  f- Similar to , but for fear training with oHFS followed by a 3-s foot-shock with a delay of 5 min, 1 h or 3 h. Significant reduction in lever pressing was found in the 5-min group (  = 6) and 1-h group (  = 7), but not in the oHFS alone group (  = 6) or 3-h group (  = 6) or vector-1-h control group (  = 6). * indicates  P g) and one-way ANOVA ( ) followed by Tukey’s multiple comparison test. - Similar to - , but for fear training with oHFS 5 min and 1 h after the foot-shock. Significant reduction in lever pressing was found in the 5-min group (  = 7) but not in the 1-h group (  = 6). The same data for the oHFS alone group in - is shown here again as a control. *** indicates  j) and one-way ANOVA ( ) followed by Tukey’s multiple comparison test