diff --git a/ars.lua b/ars.lua
index b40e314..0fe6887 100644
--- a/ars.lua
+++ b/ars.lua
@@ -119,16 +119,21 @@ function Ars:tell(scored, unperturbed_score)
     self.evals = self.evals + #scored
     if use_lips then self.evals = self.evals + 1 end
 
-    -- FIXME: the non-antithetic case seems to be broken.
-
     local indices = collect_best_indices(scored, self.poptop, self.antithetic)
 
     local top_rewards = {}
     for i = 1, #scored do top_rewards[i] = 0 end
-    for _, ind in ipairs(indices) do
-        local sind = (ind - 1) * 2 + 1
-        top_rewards[sind + 0] = scored[sind + 0]
-        top_rewards[sind + 1] = scored[sind + 1]
+    if self.antithetic then
+        for _, ind in ipairs(indices) do
+            local sind = (ind - 1) * 2 + 1
+            top_rewards[sind + 0] = scored[sind + 0]
+            top_rewards[sind + 1] = scored[sind + 1]
+        end
+    else
+        for _, i in ipairs(indices) do top_rewards[i] = scored[i] end
+        -- note: although this normalizes the scale, it's later
+        --       re-normalized differently by reward_dev anyway.
+        top_rewards = util.normalize_sums(top_rewards)
     end
 
     local step = nn.zeros(self.dims)