kjohnsen · Jun 26, 2026 · Jun 25, 2026 · Jun 26, 2026 · Jun 26, 2026 · Jun 26, 2026
diff --git a/cleo/registry.py b/cleo/registry.py
@@ -1,7 +1,8 @@
-"""Code for orchestrating inter-device interactions. 
+"""Code for orchestrating inter-device interactions.
 
 This should only be relevant for developers, not users, as this code is used
 under the hood when interacting devices are injected (e.g., light and opsin)."""
+
 from __future__ import annotations
 
 from typing import Tuple
@@ -51,7 +52,7 @@ class DeviceInteractionRegistry:
         epsilon : 1
         Ephoton : joule
         Irr_post = epsilon * T * Irr0_pre : watt/meter**2 (summed)
-        phi_post = Irr_post / Ephoton : 1/second/meter**2 (summed)
+        phi_post = epsilon * T * Irr0_pre / Ephoton : 1/second/meter**2 (summed)
     """
     """Model used in light propagation synapses"""
 

diff --git a/docs/tutorials/PI_ctrl.ipynb b/docs/tutorials/PI_ctrl.ipynb
diff --git a/docs/tutorials/advanced_lfp.ipynb b/docs/tutorials/advanced_lfp.ipynb
diff --git a/docs/tutorials/all_optical.ipynb b/docs/tutorials/all_optical.ipynb
diff --git a/docs/tutorials/electrodes.ipynb b/docs/tutorials/electrodes.ipynb
diff --git a/docs/tutorials/multi_opto.ipynb b/docs/tutorials/multi_opto.ipynb
diff --git a/docs/tutorials/neo.ipynb b/docs/tutorials/neo.ipynb
diff --git a/docs/tutorials/on_off_ctrl.ipynb b/docs/tutorials/on_off_ctrl.ipynb
diff --git a/docs/tutorials/optimal_ctrl.ipynb b/docs/tutorials/optimal_ctrl.ipynb
diff --git a/docs/tutorials/optogenetics.ipynb b/docs/tutorials/optogenetics.ipynb
diff --git a/docs/tutorials/video_visualization.ipynb b/docs/tutorials/video_visualization.ipynb
diff --git a/pyproject.toml b/pyproject.toml
@@ -35,7 +35,7 @@ dev = [
     "sphinx-favicon>=0.2,<0.3",
     "furo>=2024.1.29,<2025.0.0",
     "nbdev>=2.3.12,<3.0.0",
-    # not including elephant (used in Neo export tutorial) because of dep issues
+    "elephant",
     "seaborn>=0.13.0,<0.14.0",
     "ruff>=0.1.15,<1.0.0",
     "pytest-xdist>=3.5.0,<4.0.0",

diff --git a/tests/test_registry.py b/tests/test_registry.py
@@ -4,7 +4,7 @@
 from brian2 import Network, NeuronGroup, mm, mm2, ms, mV, mwatt, nmeter, np, umeter
 
 from cleo import CLSimulator
-from cleo.coords import assign_coords_grid_rect_prism
+from cleo.coords import assign_coords, assign_coords_grid_rect_prism
 from cleo.light import Light, fiber473nm
 from cleo.opto import Opsin, chr2_4s, vfchrimson_4s
 
@@ -146,6 +146,42 @@ def test_multi_channel(sim_ng1_ng2, ops1):
     assert np.all(v_base_x > v_yz)
 
 
+def test_light_Irr_phi_aggregation():
+    """Tests that both Irr and phi are aggregated correctly for multiple light sources"""
+    sim = CLSimulator(Network())
+    light_agg_ngs = []
+
+    for coords in (
+        [[0, 0, 0]] * mm,
+        [[0, 0, 0], [1, 0, 0]] * mm,
+        [[0, 0, 0], [1, 0, 0], [1, 0, 0]] * mm,
+    ):
+        light = Light(
+            coords=coords, light_model=fiber473nm(), name=f"light_{len(coords)}"
+        )
+        ng = NeuronGroup(len(coords), "v: volt \n Iopto : amp")
+        assign_coords(ng, coords + (0, 0, 100) * umeter)
+        sim.network.add(ng)
+        ops = chr2_4s()
+        ops.name = f"ops_{len(coords)}"
+        sim.inject(ops, ng)
+        sim.inject(light, ng)
+        light.update(1 * mwatt / mm2)
+
+        light_agg_ngs.append(ops.light_agg_ngs[ng.name])
+
+    sim.run(0.1 * ms)
+
+    irrs = [agg.Irr for agg in light_agg_ngs]
+    phis = [agg.phi for agg in light_agg_ngs]
+
+    for var in [irrs, phis]:
+        assert var[0][0] == var[1][0] == var[1][1] == var[2][0], (
+            f"{var} should be same for each neuron regardless of how many sources are present"
+        )
+        assert var[2][1] == var[0][0] * 2, f"{var} should be double for 2 sources"
+
+
 @pytest.mark.slow
 def test_multi_light_opsin(sim_ng1_ng2):
     sim, ng1, ng2 = sim_ng1_ng2