diff --git a/Runtime/Scripts/Core/Cluster.cs b/Runtime/Scripts/Core/Cluster.cs
index e200f74..4ec2fed 100644
--- a/Runtime/Scripts/Core/Cluster.cs
+++ b/Runtime/Scripts/Core/Cluster.cs
@@ -183,8 +183,10 @@ namespace NanoBrain {
                                 if (externalCluster.name == synapseData.clusterName)
                                     instanceCount = externalCluster.instanceCount;
                             }
-                            Cluster extCluster = new Cluster(extPrefab, this, instanceCount);
+                            if (this.nuclei.Find(nucleus => nucleus.name == synapseData.clusterName) is not Cluster extCluster)
+                                extCluster = new(extPrefab, this, instanceCount);
                             Neuron extNeuron = extCluster.GetNeuron(synapseData.neuronName);
+                            Debug.Log("Add receiver for external");
                             extNeuron.AddReceiver(receiver);
                         }
                     }
diff --git a/Runtime/Scripts/Core/Neuron.cs b/Runtime/Scripts/Core/Neuron.cs
index 6e4dd1b..cd74076 100644
--- a/Runtime/Scripts/Core/Neuron.cs
+++ b/Runtime/Scripts/Core/Neuron.cs
@@ -646,10 +646,9 @@ namespace NanoBrain {
         public virtual void AddReceiver(Nucleus receiverToAdd, float weight = 1, bool trainable = false) {
             if (receiverToAdd is not Neuron receiverNeuron)
                 return;
+
             this._receivers.Add(receiverNeuron);
             receiverNeuron.AddSynapse(this, weight, trainable);
-            //Debug.Log($"Add synapse {this.clusterPrefab.name}.{this.name} -> {receiverToAdd.name} --- [{this.receivers.Count}]");
-
         }
 
         /// <summary>