diff --git a/Scripts/Cog Neuro Labs/Lab1_2021_DynamicsAndPerception_v1.ipynb b/Scripts/Cog Neuro Labs/Lab1_2021_DynamicsAndPerception_v1.ipynb
index 931a1c70fd..7f6ebe087a 100644
--- a/Scripts/Cog Neuro Labs/Lab1_2021_DynamicsAndPerception_v1.ipynb	
+++ b/Scripts/Cog Neuro Labs/Lab1_2021_DynamicsAndPerception_v1.ipynb	
@@ -386,8 +386,8 @@
     "        if soft:\n",
     "            X = np.tanh(X)\n",
     "        else:\n",
-    "            X[x < 0] = -1\n",
-    "            X[x >= 0] = 1\n",
+    "            X[X < 0] = -1\n",
+    "            X[X >= 0] = 1\n",
     "        Xs[i] = X\n",
     "    return Xs\n",
     "\n",