diff --git a/Cluster.cs b/Cluster.cs
index 521a75c..22c52db 100644
--- a/Cluster.cs
+++ b/Cluster.cs
@@ -339,10 +339,18 @@ public class Cluster : Nucleus {
     }
 
     public Nucleus GetNucleus(string nucleusName) {
-        foreach (Nucleus receptor in this.nuclei) {
-            if (receptor is Nucleus nucleus)
-                if (nucleus.name == nucleusName)
-                    return nucleus;
+        foreach (Nucleus nucleus in this.nuclei) {
+            if (nucleus.name == nucleusName)
+                return nucleus;
+        }
+        return null;
+    }
+
+    public Receptor GetReceptor(string receptorName) {
+        foreach (Nucleus nucleus in this.nuclei) {
+            if (nucleus is Receptor receptor)
+                if (receptor.name == receptorName)
+                    return receptor;
         }
         return null;
     }
diff --git a/Neuron.cs b/Neuron.cs
index e32a081..315fc21 100644
--- a/Neuron.cs
+++ b/Neuron.cs
@@ -45,12 +45,6 @@ public class Neuron : Nucleus {
     public CurvePresets curvePreset {
         get { return _curvePreset; }
         set {
-            // if (this.array != null && this.array.nuclei != null) {
-            //     foreach (Neuron nucleus in this.array.nuclei.Cast<Neuron>()) {
-            //         nucleus._curvePreset = value;
-            //         nucleus.curve = GenerateCurve();
-            //     }
-            // }
             _curvePreset = value;
             this.curve = GenerateCurve();
         }
@@ -196,7 +190,6 @@ public class Neuron : Nucleus {
         foreach (Synapse synapse in this.synapses)
             sum += synapse.weight * synapse.nucleus.outputValue;
         return sum;
-        //this.outputValue = Activation(sum);
     }
 
     public float3 CombinatorProduct() {
@@ -204,7 +197,6 @@ public class Neuron : Nucleus {
         foreach (Synapse synapse in this.synapses)
             product *= synapse.weight * synapse.nucleus.outputValue;
         return product;
-        //this.outputValue = Activation(product);
     }
 
     public float3 CombinatorMax() {
diff --git a/Nucleus.cs b/Nucleus.cs
index 6ce9900..57ad5f4 100644
--- a/Nucleus.cs
+++ b/Nucleus.cs
@@ -90,44 +90,19 @@ public abstract class Nucleus {
 
     #endregion Receivers
 
-    // [SerializeReference]
-    // private NucleusArray _array;
-    // public NucleusArray array {
-    //     get { return _array; }
-    //     set { _array = value; }
-    // }
-
     #region Update
 
     public abstract void UpdateStateIsolated();
 
     public virtual void UpdateNuclei() {
-        // if (this.array == null || this.array.nuclei == null || this.array.nuclei.Length <= 1)
-        return;
-
-        // this.stale++;
-        // if (this.stale > staleValueForSleep) {
-        //     //Debug.Log($"{this.name} goes to sleep, stale = {this.stale}");
-        //     _outputValue = Vector3.zero;
-        // }
     }
 
-    public virtual void ProcessStimulus(Vector3 inputValue, int thingId = 0, string thingName = null) {
-        //this.array.ProcessStimulus(thingId, inputValue, thingName);
-        //        this.ProcessStimulus(inputValue);
+    public virtual void SetBias(Vector3 inputValue) {
         this.stale = 0;
         this.bias = inputValue;
         this.parent.UpdateFromNucleus(this);
     }
 
-    // public virtual void ProcessStimulus(int thingId, Vector3 inputValue, string thingName = null) {
-    //     // this.array.ProcessStimulus(thingId, inputValue, thingName);
-    //     //      this.ProcessStimulus(inputValue);
-    //     this.stale = 0;
-    //     this.bias = inputValue;
-    //     this.parent.UpdateFromNucleus(this);
-    // }
-
     #endregion Update
 
 }
\ No newline at end of file
diff --git a/NucleusArray.cs b/NucleusArray.cs
index 5ff9876..48595b5 100644
--- a/NucleusArray.cs
+++ b/NucleusArray.cs
@@ -130,7 +130,7 @@ public class NucleusArray {
         // Remove a thing-receiver connection when the nucleus is inactive
         List<int> receiversToRemove = new();
         foreach (KeyValuePair<int, Nucleus> item in thingReceivers) {
-            if (item.Value.isSleeping)
+            if (item.Value != null && item.Value.isSleeping)
                 receiversToRemove.Add(item.Key);            
         }
         foreach (int thingId in receiversToRemove) {
diff --git a/Receptor.cs b/Receptor.cs
index bc92f57..34c511c 100644
--- a/Receptor.cs
+++ b/Receptor.cs
@@ -30,7 +30,6 @@ public class Receptor : Neuron {
         set { _array = value; }
     }
 
-
     public override void UpdateStateIsolated() {
         this.outputValue = this.bias;
     }
@@ -43,7 +42,8 @@ public class Receptor : Neuron {
         }
     }
 
-    public override void ProcessStimulus(Vector3 inputValue, int thingId = 0, string thingName = null) {
-                this.array.ProcessStimulus(thingId, inputValue, thingName);
+    public virtual void ProcessStimulus(Vector3 inputValue, int thingId = 0, string thingName = null) {
+        this.array ??= new NucleusArray(this.parent);
+        this.array.ProcessStimulus(thingId, inputValue, thingName);
     }
 }
\ No newline at end of file
diff --git a/ReceptorArray.cs b/ReceptorArray.cs
index 1c7edeb..3ac96aa 100644
--- a/ReceptorArray.cs
+++ b/ReceptorArray.cs
@@ -141,7 +141,7 @@ public class ReceptorArray : Nucleus {
     // public override void ProcessStimulus(int thingId, Vector3 inputValue, string thingName = null) {
     //     ProcessStimulus(inputValue, thingId, thingName);
     // }
-    public override void ProcessStimulus(Vector3 inputValue, int thingId = 0, string thingName = null) {
+    public virtual void ProcessStimulus(Vector3 inputValue, int thingId = 0, string thingName = null) {
         CleanupReceivers();
         if (!thingReceivers.TryGetValue(thingId, out Nucleus selectedReceiver)) {
             //Debug.Log($" no receiver found for {thingId}");
diff --git a/Scripts/Experimental/SelectorBrain.cs b/Scripts/Experimental/SelectorBrain.cs
index 282305a..08b21f6 100644
--- a/Scripts/Experimental/SelectorBrain.cs
+++ b/Scripts/Experimental/SelectorBrain.cs
@@ -5,11 +5,11 @@ public class SelectorBrain : NanoBrain {
     public Vector3 input2;
     public Vector3 output;
 
-    public Nucleus receptor;
+    public Receptor receptor;
     //public Nucleus receptor2;
 
     protected void Awake() {
-        receptor = this.brain.GetNucleus("Selector");
+        receptor = this.brain.GetReceptor("Selector");
         //receptor2 = this.brain.GetNucleus("Selector");
     }