diff --git a/lib/ace/mode/latex_highlight_rules.js b/lib/ace/mode/latex_highlight_rules.js
index fe3ff646..19d7e83a 100644
--- a/lib/ace/mode/latex_highlight_rules.js
+++ b/lib/ace/mode/latex_highlight_rules.js
@@ -43,7 +43,7 @@ var LatexHighlightRules = function() {
             next  : "equation"
         }],
         "block" : [{
-            token : ["","variable.parameter",""],
+            token : ["lparen","variable.parameter","rparen"],
             regex : "({)([^}\\s]*)(}?)",
             next  : "start"
         },{