diff --git a/docs/source/quick.rst b/docs/source/quick.rst
index be40149..2ce33c5 100644
--- a/docs/source/quick.rst
+++ b/docs/source/quick.rst
@@ -97,7 +97,7 @@ Cells can be added to the network using :code:`create_<name>_cell()` method:
 .. note::
     The impulse-response function of ganglion cells can be set in two ways:
 
-    * It can either be given as an argument :code:`kernel` when the neuron object is created using :py:meth:`~pylgn.core.Network.create_ganglion_cell`. If no argument is given, a spatial DoG function and a temporal delta function is used.
+    * It can either be given as an argument :code:`kernel` when the neuron object is created using :py:meth:`~pylgn.core.Network.create_ganglion_cell`. If no argument is given, a spatial DoG function and a temporal biphasic function is used.
 
     * The second option is to use the :py:meth:`~pylgn.core.Ganglion.set_kernel` method after that the neuron object is created.
 
diff --git a/pylgn/core.py b/pylgn/core.py
index f9782ec..6629855 100644
--- a/pylgn/core.py
+++ b/pylgn/core.py
@@ -738,12 +738,12 @@ def __init__(self, background_response, kernel, annotations={}):
             Dictionary with various annotations.
         """
         from .kernels.spatial import create_dog_ft
-        from .kernels.temporal import create_delta_ft
+        from .kernels.temporal import create_biphasic_ft
 
         super().__init__(background_response, annotations)
 
         if kernel is None:
-            kernel = (create_dog_ft(), create_delta_ft())
+            kernel = (create_dog_ft(), create_biphasic_ft())
         self.set_kernel(kernel)
 
     def _check_if_connection_is_allowed(self, neuron):