From 53f4f8c1c60f0821c83df4fd6c38c2a3bbe80c47 Mon Sep 17 00:00:00 2001
From: Edouard <edouard.delaire@icloud.com>
Date: Fri, 8 May 2026 20:23:57 -0400
Subject: [PATCH 01/16] WIP add headmodel computation

---
 toolbox/forward/bst_headmodeler.m |  9 +++-
 toolbox/forward/bst_seeg_uni.m    | 70 +++++++++++++++++++++++++++++++
 2 files changed, 78 insertions(+), 1 deletion(-)
 create mode 100644 toolbox/forward/bst_seeg_uni.m

diff --git a/toolbox/forward/bst_headmodeler.m b/toolbox/forward/bst_headmodeler.m
index 6af5e4dca..581fbdfc6 100644
--- a/toolbox/forward/bst_headmodeler.m
+++ b/toolbox/forward/bst_headmodeler.m
@@ -22,7 +22,7 @@
 %     .EEGMethod:  Method used to compute the forward model for EEG sensors.
 %         - 'eeg_3sphereberg' : EEG forward modeling with a set of 3 concentric spheres (Scalp, Skull, Brain/CSF) 
 %         - 'openmeeg'        : OpenMEEG forward model
-%     .SEEGMethod:    'openmeeg' and 'duneuro'  
+%     .SEEGMethod:    'uniform', 'openmeeg' and 'duneuro'  
 %     .ECOGMethod:    'openmeeg' and 'duneuro' 
 %     .NIRSMethod:    'import'
 %
@@ -536,6 +536,13 @@
     Gain(~isnan(Gain_dn)) = Gain_dn(~isnan(Gain_dn));
 end
 
+%% ===== COMPUTE: SEEG UNIFORM HEADMODELS =====
+if strcmp('uniform', OPTIONS.SEEGMethod)
+
+    Gain(iSeeg, :) =  bst_seeg_uni(OPTIONS.GridLoc, OPTIONS.Channel(iSeeg), sSurfInner, []);
+    strHistory =  [strHistory, ' | ', 'Uniform medium (SEEG)',  ' | ', sprintf('Cond: %1.3f', OPTIONS.Conductivity)];
+end
+
 
 %% ===== COMPUTE: BRAINSTORM HEADMODELS =====
 Param = [];
diff --git a/toolbox/forward/bst_seeg_uni.m b/toolbox/forward/bst_seeg_uni.m
new file mode 100644
index 000000000..55310e0cc
--- /dev/null
+++ b/toolbox/forward/bst_seeg_uni.m
@@ -0,0 +1,70 @@
+function G = bst_seeg_uni(GridLoc, sChannel, sInnerSkull, Options)
+% BST_EEG_SPH: Calculate the electric potential, spherical head, arbitrary orientation
+%
+% USAGE:  G = bst_eeg_sph(Rq, Channel, center, R, sigma);
+%
+% INPUT:
+%    - GridLoc     : dipole location(in meters)    [nDipoles x 3]
+%    - Channel     : a Brainstorm channel structure  [nSensors]  
+%    - sInnerSkull : Inner skull surface
+%    - Options structure
+%       - Options.sigma : conductivity
+%       - Options.minDistance : in meter
+
+    % Add default options
+    Options = struct_copy_fields(struct('sigma', 0.25, 'minDistance', 3/1000), Options, 1);
+    min_distance        = Options.minDistance;
+    sigma0              = Options.sigma;
+
+
+    NbElectrodes = length(sChannel);
+    NbVertices   = size(GridLoc, 1);
+
+    % Find electrodes that are inside the inner skull
+    SEEG_Loc = zeros(NbElectrodes, 3);
+    for iEEG = 1:NbElectrodes
+        SEEG_Loc(iEEG, :) = sChannel(iEEG).Loc;
+    end
+    isSEEGInsideSkull   = inpolyhd(SEEG_Loc, sInnerSkull.Vertices, sInnerSkull.Faces);
+    
+    % Compute the leadfield
+    G = zeros(NbElectrodes , 3*NbVertices);
+    for iContact =  1:NbElectrodes
+        
+        if ~isSEEGInsideSkull(iContact)
+            continue
+        end
+
+        VectorSEEGtoCortex =  SEEG_Loc(iContact, :) - GridLoc;
+        DistanceToCortex = vecnorm(VectorSEEGtoCortex, 2, 2)';
+
+        % Filter short distance
+        iShort =  find(DistanceToCortex < min_distance);
+        if ~isempty(iShort)
+            fprintf(' %d vertex had distance to the cortex smaller than %.2f mm to electrodes %s \n', length(iShort), min_distance*1000, sChannel(iContact).Name);
+            
+            
+            VectorSEEGtoCortex(iShort, 1) = ( VectorSEEGtoCortex(iShort, 1) ./ DistanceToCortex(iShort)') * min_distance; 
+            VectorSEEGtoCortex(iShort, 2) = ( VectorSEEGtoCortex(iShort, 2) ./ DistanceToCortex(iShort)') * min_distance; 
+            VectorSEEGtoCortex(iShort, 3) = ( VectorSEEGtoCortex(iShort, 3) ./ DistanceToCortex(iShort)') * min_distance; 
+
+            DistanceToCortex(iShort) =  min_distance;
+        end
+
+        % Normalize the vector
+        VectorSEEGtoCortex(:, 1) = ( VectorSEEGtoCortex(:, 1) ./ DistanceToCortex'); 
+        VectorSEEGtoCortex(:, 2) = ( VectorSEEGtoCortex(:, 2) ./ DistanceToCortex'); 
+        VectorSEEGtoCortex(:, 3) = ( VectorSEEGtoCortex(:, 3) ./ DistanceToCortex'); 
+
+
+        % Compute the leadfiels 
+        for ind_vert = 1:NbVertices
+            G(iContact, 3*(ind_vert-1) + 1) = dot([1, 0, 0], VectorSEEGtoCortex(ind_vert, :)) / DistanceToCortex(ind_vert)^2 ;  
+            G(iContact, 3*(ind_vert-1) + 2) = dot([0, 1, 0], VectorSEEGtoCortex(ind_vert, :)) / DistanceToCortex(ind_vert)^2 ;  
+            G(iContact, 3*(ind_vert-1) + 3) = dot([0, 0, 1], VectorSEEGtoCortex(ind_vert, :)) / DistanceToCortex(ind_vert)^2 ;  
+        end
+
+        % Add normalization constant 
+        G = G / (4 * pi * sigma0);
+    end
+end
\ No newline at end of file

From 21a656e11e7424df4249e367c20b84646d50f2b7 Mon Sep 17 00:00:00 2001
From: Edouard <edouard.delaire@icloud.com>
Date: Fri, 8 May 2026 20:45:26 -0400
Subject: [PATCH 02/16] improve code. Compute for x,y,z

---
 toolbox/forward/bst_seeg_uni.m | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/toolbox/forward/bst_seeg_uni.m b/toolbox/forward/bst_seeg_uni.m
index 55310e0cc..776e7012b 100644
--- a/toolbox/forward/bst_seeg_uni.m
+++ b/toolbox/forward/bst_seeg_uni.m
@@ -28,6 +28,7 @@
     isSEEGInsideSkull   = inpolyhd(SEEG_Loc, sInnerSkull.Vertices, sInnerSkull.Faces);
     
     % Compute the leadfield
+    bst_progress('start', 'Computing head model', sprintf('Computing head model for %d contacts...', NbElectrodes), 0, NbElectrodes);
     G = zeros(NbElectrodes , 3*NbVertices);
     for iContact =  1:NbElectrodes
         
@@ -59,12 +60,16 @@
 
         % Compute the leadfiels 
         for ind_vert = 1:NbVertices
-            G(iContact, 3*(ind_vert-1) + 1) = dot([1, 0, 0], VectorSEEGtoCortex(ind_vert, :)) / DistanceToCortex(ind_vert)^2 ;  
-            G(iContact, 3*(ind_vert-1) + 2) = dot([0, 1, 0], VectorSEEGtoCortex(ind_vert, :)) / DistanceToCortex(ind_vert)^2 ;  
-            G(iContact, 3*(ind_vert-1) + 3) = dot([0, 0, 1], VectorSEEGtoCortex(ind_vert, :)) / DistanceToCortex(ind_vert)^2 ;  
+            G(iContact, 3*(ind_vert-1) + 1) = VectorSEEGtoCortex(ind_vert, 1) / DistanceToCortex(ind_vert)^2 ;  
+            G(iContact, 3*(ind_vert-1) + 2) = VectorSEEGtoCortex(ind_vert, 2) / DistanceToCortex(ind_vert)^2 ;  
+            G(iContact, 3*(ind_vert-1) + 3) = VectorSEEGtoCortex(ind_vert, 3) / DistanceToCortex(ind_vert)^2 ;  
         end
 
-        % Add normalization constant 
-        G = G / (4 * pi * sigma0);
+        bst_progress('inc', 1);
     end
+
+    % Add normalization constant 
+    G = G / (4 * pi * sigma0);
+
+    bst_progress('stop');
 end
\ No newline at end of file

From f89fc16c8283bdbecc9e944f3ec565540828d2ce Mon Sep 17 00:00:00 2001
From: Edouard <edouard.delaire@icloud.com>
Date: Fri, 8 May 2026 21:07:05 -0400
Subject: [PATCH 03/16] Add the option on the panel

---
 toolbox/forward/panel_headmodel.m | 1 +
 1 file changed, 1 insertion(+)

diff --git a/toolbox/forward/panel_headmodel.m b/toolbox/forward/panel_headmodel.m
index 21575109f..d3eb991da 100644
--- a/toolbox/forward/panel_headmodel.m
+++ b/toolbox/forward/panel_headmodel.m
@@ -121,6 +121,7 @@
         jCheckMethodSEEG.setSelected(1);
         % Combobox
         jComboMethodSEEG = gui_component('ComboBox', jPanelMethod, 'tab hfill', [], [], [], @UpdateComment, []);
+        jComboMethodSEEG.addItem(BstListItem('uniform', '', 'Uniform medium', []));
         jComboMethodSEEG.addItem(BstListItem('openmeeg', '', 'OpenMEEG BEM', []));
         jComboMethodSEEG.addItem(BstListItem('duneuro', '', 'DUNEuro FEM', []));
         jComboMethodSEEG.setSelectedIndex(0);

From 9a6d906706488193a4672f58ba5e2871556a1f52 Mon Sep 17 00:00:00 2001
From: Edouard <edouard.delaire@icloud.com>
Date: Fri, 8 May 2026 21:07:12 -0400
Subject: [PATCH 04/16] simplify code

---
 toolbox/forward/bst_seeg_uni.m | 31 +++++++++++--------------------
 1 file changed, 11 insertions(+), 20 deletions(-)

diff --git a/toolbox/forward/bst_seeg_uni.m b/toolbox/forward/bst_seeg_uni.m
index 776e7012b..de76382a0 100644
--- a/toolbox/forward/bst_seeg_uni.m
+++ b/toolbox/forward/bst_seeg_uni.m
@@ -16,15 +16,11 @@
     min_distance        = Options.minDistance;
     sigma0              = Options.sigma;
 
-
     NbElectrodes = length(sChannel);
     NbVertices   = size(GridLoc, 1);
 
     % Find electrodes that are inside the inner skull
-    SEEG_Loc = zeros(NbElectrodes, 3);
-    for iEEG = 1:NbElectrodes
-        SEEG_Loc(iEEG, :) = sChannel(iEEG).Loc;
-    end
+    SEEG_Loc = [sChannel.Loc]'; 
     isSEEGInsideSkull   = inpolyhd(SEEG_Loc, sInnerSkull.Vertices, sInnerSkull.Faces);
     
     % Compute the leadfield
@@ -37,33 +33,28 @@
         end
 
         VectorSEEGtoCortex =  SEEG_Loc(iContact, :) - GridLoc;
-        DistanceToCortex = vecnorm(VectorSEEGtoCortex, 2, 2)';
+        DistanceToCortex = vecnorm(VectorSEEGtoCortex, 2, 2);
 
         % Filter short distance
         iShort =  find(DistanceToCortex < min_distance);
         if ~isempty(iShort)
             fprintf(' %d vertex had distance to the cortex smaller than %.2f mm to electrodes %s \n', length(iShort), min_distance*1000, sChannel(iContact).Name);
             
-            
-            VectorSEEGtoCortex(iShort, 1) = ( VectorSEEGtoCortex(iShort, 1) ./ DistanceToCortex(iShort)') * min_distance; 
-            VectorSEEGtoCortex(iShort, 2) = ( VectorSEEGtoCortex(iShort, 2) ./ DistanceToCortex(iShort)') * min_distance; 
-            VectorSEEGtoCortex(iShort, 3) = ( VectorSEEGtoCortex(iShort, 3) ./ DistanceToCortex(iShort)') * min_distance; 
+            VectorSEEGtoCortex(iShort, 1) = ( VectorSEEGtoCortex(iShort, 1) ./ DistanceToCortex(iShort)) * min_distance; 
+            VectorSEEGtoCortex(iShort, 2) = ( VectorSEEGtoCortex(iShort, 2) ./ DistanceToCortex(iShort)) * min_distance; 
+            VectorSEEGtoCortex(iShort, 3) = ( VectorSEEGtoCortex(iShort, 3) ./ DistanceToCortex(iShort)) * min_distance; 
 
             DistanceToCortex(iShort) =  min_distance;
         end
 
         % Normalize the vector
-        VectorSEEGtoCortex(:, 1) = ( VectorSEEGtoCortex(:, 1) ./ DistanceToCortex'); 
-        VectorSEEGtoCortex(:, 2) = ( VectorSEEGtoCortex(:, 2) ./ DistanceToCortex'); 
-        VectorSEEGtoCortex(:, 3) = ( VectorSEEGtoCortex(:, 3) ./ DistanceToCortex'); 
-
+        VectorSEEGtoCortex = VectorSEEGtoCortex(:, 1) ./ repmat(DistanceToCortex, 1, 3); 
+        
+        % Compute the leadfield
+        scaledVector = VectorSEEGtoCortex ./ repmat(DistanceToCortex.^2, 1, 3); 
 
-        % Compute the leadfiels 
-        for ind_vert = 1:NbVertices
-            G(iContact, 3*(ind_vert-1) + 1) = VectorSEEGtoCortex(ind_vert, 1) / DistanceToCortex(ind_vert)^2 ;  
-            G(iContact, 3*(ind_vert-1) + 2) = VectorSEEGtoCortex(ind_vert, 2) / DistanceToCortex(ind_vert)^2 ;  
-            G(iContact, 3*(ind_vert-1) + 3) = VectorSEEGtoCortex(ind_vert, 3) / DistanceToCortex(ind_vert)^2 ;  
-        end
+        % Organize the matrix as x,y,z
+        G(iContact, :) = reshape(scaledVector', 1, []);
 
         bst_progress('inc', 1);
     end

From 47eb805647f54a76e6edb6db97ac430a822cd34f Mon Sep 17 00:00:00 2001
From: Edouard <edouard.delaire@icloud.com>
Date: Fri, 8 May 2026 21:11:38 -0400
Subject: [PATCH 05/16] bug fix...

---
 toolbox/forward/bst_seeg_uni.m | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/toolbox/forward/bst_seeg_uni.m b/toolbox/forward/bst_seeg_uni.m
index de76382a0..0c30098cd 100644
--- a/toolbox/forward/bst_seeg_uni.m
+++ b/toolbox/forward/bst_seeg_uni.m
@@ -48,7 +48,7 @@
         end
 
         % Normalize the vector
-        VectorSEEGtoCortex = VectorSEEGtoCortex(:, 1) ./ repmat(DistanceToCortex, 1, 3); 
+        VectorSEEGtoCortex = VectorSEEGtoCortex ./ repmat(DistanceToCortex, 1, 3); 
         
         % Compute the leadfield
         scaledVector = VectorSEEGtoCortex ./ repmat(DistanceToCortex.^2, 1, 3); 

From f3883de73c4e7d606227c38c3589846464b93d34 Mon Sep 17 00:00:00 2001
From: Edouard <edouard.delaire@icloud.com>
Date: Fri, 8 May 2026 21:43:04 -0400
Subject: [PATCH 06/16] fix vector name

---
 toolbox/forward/bst_seeg_uni.m | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/toolbox/forward/bst_seeg_uni.m b/toolbox/forward/bst_seeg_uni.m
index 0c30098cd..de50ec5bf 100644
--- a/toolbox/forward/bst_seeg_uni.m
+++ b/toolbox/forward/bst_seeg_uni.m
@@ -32,26 +32,26 @@
             continue
         end
 
-        VectorSEEGtoCortex =  SEEG_Loc(iContact, :) - GridLoc;
-        DistanceToCortex = vecnorm(VectorSEEGtoCortex, 2, 2);
+        VectorCortexToSEEG =  SEEG_Loc(iContact, :) - GridLoc;
+        DistanceToCortex = vecnorm(VectorCortexToSEEG, 2, 2);
 
         % Filter short distance
         iShort =  find(DistanceToCortex < min_distance);
         if ~isempty(iShort)
             fprintf(' %d vertex had distance to the cortex smaller than %.2f mm to electrodes %s \n', length(iShort), min_distance*1000, sChannel(iContact).Name);
             
-            VectorSEEGtoCortex(iShort, 1) = ( VectorSEEGtoCortex(iShort, 1) ./ DistanceToCortex(iShort)) * min_distance; 
-            VectorSEEGtoCortex(iShort, 2) = ( VectorSEEGtoCortex(iShort, 2) ./ DistanceToCortex(iShort)) * min_distance; 
-            VectorSEEGtoCortex(iShort, 3) = ( VectorSEEGtoCortex(iShort, 3) ./ DistanceToCortex(iShort)) * min_distance; 
+            VectorCortexToSEEG(iShort, 1) = ( VectorCortexToSEEG(iShort, 1) ./ DistanceToCortex(iShort)) * min_distance; 
+            VectorCortexToSEEG(iShort, 2) = ( VectorCortexToSEEG(iShort, 2) ./ DistanceToCortex(iShort)) * min_distance; 
+            VectorCortexToSEEG(iShort, 3) = ( VectorCortexToSEEG(iShort, 3) ./ DistanceToCortex(iShort)) * min_distance; 
 
             DistanceToCortex(iShort) =  min_distance;
         end
 
         % Normalize the vector
-        VectorSEEGtoCortex = VectorSEEGtoCortex ./ repmat(DistanceToCortex, 1, 3); 
+        VectorCortexToSEEG = VectorCortexToSEEG ./ repmat(DistanceToCortex, 1, 3); 
         
         % Compute the leadfield
-        scaledVector = VectorSEEGtoCortex ./ repmat(DistanceToCortex.^2, 1, 3); 
+        scaledVector = VectorCortexToSEEG ./ repmat(DistanceToCortex.^2, 1, 3); 
 
         % Organize the matrix as x,y,z
         G(iContact, :) = reshape(scaledVector', 1, []);

From 929286c362a45c1147a44d4b59f8b33b3e75d8e4 Mon Sep 17 00:00:00 2001
From: Edouard <edouard.delaire@icloud.com>
Date: Fri, 8 May 2026 23:09:10 -0400
Subject: [PATCH 07/16] Add documentation

---
 toolbox/forward/bst_seeg_uni.m | 43 ++++++++++++++++++++++++++++++++--
 1 file changed, 41 insertions(+), 2 deletions(-)

diff --git a/toolbox/forward/bst_seeg_uni.m b/toolbox/forward/bst_seeg_uni.m
index de50ec5bf..0b760fbed 100644
--- a/toolbox/forward/bst_seeg_uni.m
+++ b/toolbox/forward/bst_seeg_uni.m
@@ -1,7 +1,7 @@
 function G = bst_seeg_uni(GridLoc, sChannel, sInnerSkull, Options)
-% BST_EEG_SPH: Calculate the electric potential, spherical head, arbitrary orientation
+% bst_seeg_uni: Calculate the electric potential, spherical head, arbitrary orientation
 %
-% USAGE:  G = bst_eeg_sph(Rq, Channel, center, R, sigma);
+% USAGE:  G = bst_eeg_sph(GridLoc, sChannel, sInnerSkull, Options);
 %
 % INPUT:
 %    - GridLoc     : dipole location(in meters)    [nDipoles x 3]
@@ -10,6 +10,45 @@
 %    - Options structure
 %       - Options.sigma : conductivity
 %       - Options.minDistance : in meter
+% OUTPUTS:
+%    - G : EEG forward model gain matrix    [nSensors x (3*nDipoles)]
+%
+% DESCRIPTION:  sEEG single layer forward model
+%     This function computes the voltage potential forward gain matrix for an array of 
+%     sEEG electrodes inside the brain. The conductivity is assumed to be uniform and isotropoic
+%     inside the nedium (that is assumed to be infinite).
+%       
+%     For electrodes outside of the brain, the grain is set to 0. 
+% 
+%     Ref: 
+%          + Grova, C., Aiguabella, M., Zelmann, R., Lina, J.-M., Hall, J.A. and Kobayashi, E. (2016), 
+%            Intracranial EEG potentials estimated from MEG sources: A new approach to correlate MEG and iEEG data in epilepsy. 
+%            Hum. Brain Mapp., 37: 1661-1683. https://doi.org/10.1002/hbm.23127
+%   
+%          + Næss, S., Halnes, G., Hagen, E., Hagler Jr, D. J., Dale, A. M., Einevoll, G. T., & Ness, T. V. (2021). 
+%            Biophysically detailed forward modeling of the neural origin of EEG and MEG signals. NeuroImage, 225, 117467.  
+%           
+
+% @=============================================================================
+% This function is part of the Brainstorm software:
+% https://neuroimage.usc.edu/brainstorm
+% 
+% Copyright (c) University of Southern California & McGill University
+% This software is distributed under the terms of the GNU General Public License
+% as published by the Free Software Foundation. Further details on the GPLv3
+% license can be found at http://www.gnu.org/copyleft/gpl.html.
+% 
+% FOR RESEARCH PURPOSES ONLY. THE SOFTWARE IS PROVIDED "AS IS," AND THE
+% UNIVERSITY OF SOUTHERN CALIFORNIA AND ITS COLLABORATORS DO NOT MAKE ANY
+% WARRANTY, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO WARRANTIES OF
+% MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, NOR DO THEY ASSUME ANY
+% LIABILITY OR RESPONSIBILITY FOR THE USE OF THIS SOFTWARE.
+%
+% For more information type "brainstorm license" at command prompt.
+% =============================================================================@
+%
+% Authors: Edouard Delaire (2026)
+
 
     % Add default options
     Options = struct_copy_fields(struct('sigma', 0.25, 'minDistance', 3/1000), Options, 1);

From d1d9b605ae43b5e9a214965e5a7d74119f38300b Mon Sep 17 00:00:00 2001
From: Edouard <edouard.delaire@icloud.com>
Date: Sun, 10 May 2026 20:24:31 -0400
Subject: [PATCH 08/16] simplify code

---
 toolbox/forward/bst_seeg_uni.m | 13 ++++---------
 1 file changed, 4 insertions(+), 9 deletions(-)

diff --git a/toolbox/forward/bst_seeg_uni.m b/toolbox/forward/bst_seeg_uni.m
index 0b760fbed..112c3356e 100644
--- a/toolbox/forward/bst_seeg_uni.m
+++ b/toolbox/forward/bst_seeg_uni.m
@@ -74,21 +74,16 @@
         VectorCortexToSEEG =  SEEG_Loc(iContact, :) - GridLoc;
         DistanceToCortex = vecnorm(VectorCortexToSEEG, 2, 2);
 
+        % Normalize the vector
+        VectorCortexToSEEG = VectorCortexToSEEG ./ repmat(DistanceToCortex, 1, 3);
+
         % Filter short distance
         iShort =  find(DistanceToCortex < min_distance);
         if ~isempty(iShort)
-            fprintf(' %d vertex had distance to the cortex smaller than %.2f mm to electrodes %s \n', length(iShort), min_distance*1000, sChannel(iContact).Name);
-            
-            VectorCortexToSEEG(iShort, 1) = ( VectorCortexToSEEG(iShort, 1) ./ DistanceToCortex(iShort)) * min_distance; 
-            VectorCortexToSEEG(iShort, 2) = ( VectorCortexToSEEG(iShort, 2) ./ DistanceToCortex(iShort)) * min_distance; 
-            VectorCortexToSEEG(iShort, 3) = ( VectorCortexToSEEG(iShort, 3) ./ DistanceToCortex(iShort)) * min_distance; 
-
+            fprintf(' %d vertex had distance to the cortex smaller than %.2f mm to electrodes %s \n', length(iShort), min_distance*1000, sChannel(iContact).Name);           
             DistanceToCortex(iShort) =  min_distance;
         end
 
-        % Normalize the vector
-        VectorCortexToSEEG = VectorCortexToSEEG ./ repmat(DistanceToCortex, 1, 3); 
-        
         % Compute the leadfield
         scaledVector = VectorCortexToSEEG ./ repmat(DistanceToCortex.^2, 1, 3); 
 

From 069580f3ee1720389c74d2cde087eb3e8adb9f2b Mon Sep 17 00:00:00 2001
From: Edouard <edouard.delaire@icloud.com>
Date: Sun, 10 May 2026 20:41:02 -0400
Subject: [PATCH 09/16] Fix vector name

When considereing volume model, the dipole is not always inside the cortex
---
 toolbox/forward/bst_seeg_uni.m | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/toolbox/forward/bst_seeg_uni.m b/toolbox/forward/bst_seeg_uni.m
index 112c3356e..3a8ee49a2 100644
--- a/toolbox/forward/bst_seeg_uni.m
+++ b/toolbox/forward/bst_seeg_uni.m
@@ -49,7 +49,6 @@
 %
 % Authors: Edouard Delaire (2026)
 
-
     % Add default options
     Options = struct_copy_fields(struct('sigma', 0.25, 'minDistance', 3/1000), Options, 1);
     min_distance        = Options.minDistance;
@@ -71,21 +70,21 @@
             continue
         end
 
-        VectorCortexToSEEG =  SEEG_Loc(iContact, :) - GridLoc;
-        DistanceToCortex = vecnorm(VectorCortexToSEEG, 2, 2);
+        VectorDipolesToSEEG =  SEEG_Loc(iContact, :) - GridLoc;
+        DistanceToDipoles = vecnorm(VectorDipolesToSEEG, 2, 2);
 
         % Normalize the vector
-        VectorCortexToSEEG = VectorCortexToSEEG ./ repmat(DistanceToCortex, 1, 3);
+        VectorDipolesToSEEG = VectorDipolesToSEEG ./ repmat(DistanceToDipoles, 1, 3);
 
         % Filter short distance
-        iShort =  find(DistanceToCortex < min_distance);
+        iShort =  find(DistanceToDipoles < min_distance);
         if ~isempty(iShort)
             fprintf(' %d vertex had distance to the cortex smaller than %.2f mm to electrodes %s \n', length(iShort), min_distance*1000, sChannel(iContact).Name);           
-            DistanceToCortex(iShort) =  min_distance;
+            DistanceToDipoles(iShort) =  min_distance;
         end
 
         % Compute the leadfield
-        scaledVector = VectorCortexToSEEG ./ repmat(DistanceToCortex.^2, 1, 3); 
+        scaledVector = VectorDipolesToSEEG ./ repmat(DistanceToDipoles.^2, 1, 3); 
 
         % Organize the matrix as x,y,z
         G(iContact, :) = reshape(scaledVector', 1, []);

From 2b3458f9c532f3c2e0b7d0b952f1a834d0b93fd7 Mon Sep 17 00:00:00 2001
From: Edouard <edouard.delaire@icloud.com>
Date: Mon, 11 May 2026 19:29:10 -0400
Subject: [PATCH 10/16] wip -- add options

---
 toolbox/forward/bst_headmodeler.m | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/toolbox/forward/bst_headmodeler.m b/toolbox/forward/bst_headmodeler.m
index 581fbdfc6..542a37e8e 100644
--- a/toolbox/forward/bst_headmodeler.m
+++ b/toolbox/forward/bst_headmodeler.m
@@ -539,7 +539,29 @@
 %% ===== COMPUTE: SEEG UNIFORM HEADMODELS =====
 if strcmp('uniform', OPTIONS.SEEGMethod)
 
-    Gain(iSeeg, :) =  bst_seeg_uni(OPTIONS.GridLoc, OPTIONS.Channel(iSeeg), sSurfInner, []);
+    if ~isfield(OPTIONS, 'sigma') ||  ~isfield(OPTIONS, 'minDistance')
+        % Get options
+        prompt = {'Brain conductivity (S/m):','Minimum distance between SEEG and dipoles (mm):'};
+        sOptions = inputdlg(prompt, 'SEEG head model options',  [1 45; 1 45], {'0.25','3'});
+
+        if isempty(sOptions)
+            errMessage = 'Canceled by user.';
+            OPTIONS = [];
+            return;
+        end
+
+        try
+            OPTIONS.sigma  = str2double(sOptions{1});
+        catch
+        end
+    
+        try
+            OPTIONS.minDistance  = str2double(sOptions{2}) / 1000;
+        catch
+        end
+    end
+
+    Gain(iSeeg, :) =  bst_seeg_uni(OPTIONS.GridLoc, OPTIONS.Channel(iSeeg), sSurfInner, OPTIONS);
     strHistory =  [strHistory, ' | ', 'Uniform medium (SEEG)',  ' | ', sprintf('Cond: %1.3f', OPTIONS.Conductivity)];
 end
 

From a4504613927e244b7b0069c2c286cd9e06864bb5 Mon Sep 17 00:00:00 2001
From: Edouard <edouard.delaire@icloud.com>
Date: Mon, 11 May 2026 20:16:07 -0400
Subject: [PATCH 11/16] use java_dialogs

---
 toolbox/forward/bst_headmodeler.m | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/toolbox/forward/bst_headmodeler.m b/toolbox/forward/bst_headmodeler.m
index 542a37e8e..98bb48d8d 100644
--- a/toolbox/forward/bst_headmodeler.m
+++ b/toolbox/forward/bst_headmodeler.m
@@ -540,9 +540,10 @@
 if strcmp('uniform', OPTIONS.SEEGMethod)
 
     if ~isfield(OPTIONS, 'sigma') ||  ~isfield(OPTIONS, 'minDistance')
+        
         % Get options
         prompt = {'Brain conductivity (S/m):','Minimum distance between SEEG and dipoles (mm):'};
-        sOptions = inputdlg(prompt, 'SEEG head model options',  [1 45; 1 45], {'0.25','3'});
+        sOptions = java_dialog('input', prompt, 'SEEG head model options', [],  {'0.25','3'});
 
         if isempty(sOptions)
             errMessage = 'Canceled by user.';

From 2be782b86e8da628b503f667f56800147f590a22 Mon Sep 17 00:00:00 2001
From: rcassani <raymundo.cassani@gmail.com>
Date: Tue, 26 May 2026 13:45:57 -0400
Subject: [PATCH 12/16] Move interaction to `panel_headmodel.m`

---
 toolbox/forward/bst_headmodeler.m | 24 ----------------------
 toolbox/forward/bst_seeg_uni.m    | 10 ++++-----
 toolbox/forward/panel_headmodel.m | 34 +++++++++++++++++++++++++++++++
 3 files changed, 39 insertions(+), 29 deletions(-)

diff --git a/toolbox/forward/bst_headmodeler.m b/toolbox/forward/bst_headmodeler.m
index 98bb48d8d..03558fb61 100644
--- a/toolbox/forward/bst_headmodeler.m
+++ b/toolbox/forward/bst_headmodeler.m
@@ -538,30 +538,6 @@
 
 %% ===== COMPUTE: SEEG UNIFORM HEADMODELS =====
 if strcmp('uniform', OPTIONS.SEEGMethod)
-
-    if ~isfield(OPTIONS, 'sigma') ||  ~isfield(OPTIONS, 'minDistance')
-        
-        % Get options
-        prompt = {'Brain conductivity (S/m):','Minimum distance between SEEG and dipoles (mm):'};
-        sOptions = java_dialog('input', prompt, 'SEEG head model options', [],  {'0.25','3'});
-
-        if isempty(sOptions)
-            errMessage = 'Canceled by user.';
-            OPTIONS = [];
-            return;
-        end
-
-        try
-            OPTIONS.sigma  = str2double(sOptions{1});
-        catch
-        end
-    
-        try
-            OPTIONS.minDistance  = str2double(sOptions{2}) / 1000;
-        catch
-        end
-    end
-
     Gain(iSeeg, :) =  bst_seeg_uni(OPTIONS.GridLoc, OPTIONS.Channel(iSeeg), sSurfInner, OPTIONS);
     strHistory =  [strHistory, ' | ', 'Uniform medium (SEEG)',  ' | ', sprintf('Cond: %1.3f', OPTIONS.Conductivity)];
 end
diff --git a/toolbox/forward/bst_seeg_uni.m b/toolbox/forward/bst_seeg_uni.m
index 3a8ee49a2..fe198fe99 100644
--- a/toolbox/forward/bst_seeg_uni.m
+++ b/toolbox/forward/bst_seeg_uni.m
@@ -8,8 +8,8 @@
 %    - Channel     : a Brainstorm channel structure  [nSensors]  
 %    - sInnerSkull : Inner skull surface
 %    - Options structure
-%       - Options.sigma : conductivity
-%       - Options.minDistance : in meter
+%       - Options.Conductivity      : Conductivity (S/m)
+%       - Options.MinSeegDipoleDist : Minimum distance between SEEG and dipoles
 % OUTPUTS:
 %    - G : EEG forward model gain matrix    [nSensors x (3*nDipoles)]
 %
@@ -50,9 +50,9 @@
 % Authors: Edouard Delaire (2026)
 
     % Add default options
-    Options = struct_copy_fields(struct('sigma', 0.25, 'minDistance', 3/1000), Options, 1);
-    min_distance        = Options.minDistance;
-    sigma0              = Options.sigma;
+    Options = struct_copy_fields(struct('Conductivity', 0.25, 'MinSeegDipoleDist', 3/1000), Options, 1);
+    min_distance = Options.MinSeegDipoleDist;
+    sigma0       = Options.Conductivity;
 
     NbElectrodes = length(sChannel);
     NbVertices   = size(GridLoc, 1);
diff --git a/toolbox/forward/panel_headmodel.m b/toolbox/forward/panel_headmodel.m
index d3eb991da..38c7c767d 100644
--- a/toolbox/forward/panel_headmodel.m
+++ b/toolbox/forward/panel_headmodel.m
@@ -438,6 +438,7 @@ function UpdateComment(varargin)
         sMethod.Comment = strrep(sMethod.Comment, 'os_meg',          'Overlapping spheres');
         sMethod.Comment = strrep(sMethod.Comment, 'meg_sphere',      'Single sphere');
         sMethod.Comment = strrep(sMethod.Comment, 'eeg_3sphereberg', '3-shell sphere');
+        sMethod.Comment = strrep(sMethod.Comment, 'uniform',         'Uniform medium');
         sMethod.Comment = strrep(sMethod.Comment, 'openmeeg',        'OpenMEEG BEM');
         sMethod.Comment = strrep(sMethod.Comment, 'duneuro',         'DUNEuro FEM');
         % Grid type
@@ -447,6 +448,7 @@ function UpdateComment(varargin)
             sMethod.Comment = [sMethod.Comment ' (mixed)'];
         end
     end
+    isUniform = any(strcmpi(allMethods, 'uniform'));
     isOpenMEEG = any(strcmpi(allMethods, 'openmeeg'));
     isDuneuro = any(strcmpi(allMethods, 'duneuro'));
     % Get protocol description
@@ -598,6 +600,38 @@ function UpdateComment(varargin)
             bst_error('Please import a cortex surface for this subject.', 'Head model', 0);
             return
         end
+
+        % ===== UNIFORM =====
+        if isUniform
+            % Interactive interface to set the OpenMEEG options
+            if OPTIONS.Interactive
+                OPTIONS.Conductivity = [];
+                OPTIONS.MinSeegDipoleDist  = [];
+                % Get options
+                optionsStr = {'Brain conductivity (S/m):','Minimum distance between SEEG and dipoles (mm):'};
+                res = java_dialog('input', optionsStr, 'SEEG head model options', [],  {'0.25','3'});
+                if isempty(res)
+                    return
+                end
+                resDouble = str2double(res);
+                % Validate inputs
+                for iRes = 1 : length(resDouble)
+                    if isnan(resDouble(iRes))
+                        errMessage = sprintf('Invalid input "%s" for option:\n%s', res{iRes}, optionsStr{iRes});
+                        return
+                    end
+                end
+                OPTIONS.Conductivity      = resDouble(1);
+                OPTIONS.MinSeegDipoleDist = resDouble(2)/1000;
+            end
+            % Check that inner skull exists
+            if ~isempty(sSubject.iInnerSkull)
+                OPTIONS.InnerSkullFile = file_fullpath(sSubject.Surface(sSubject.iInnerSkull(1)).FileName);
+            else
+                errMessage = 'No inner skull surface for this subject.';
+                return
+            end
+        end
                 
         % ===== OPENMEEG =====
         if isOpenMEEG

From 4636f0857dea46b834a385f8b792b65c9129f90c Mon Sep 17 00:00:00 2001
From: rcassani <raymundo.cassani@gmail.com>
Date: Tue, 26 May 2026 13:52:58 -0400
Subject: [PATCH 13/16] Add all parameters to `History`

---
 toolbox/forward/bst_headmodeler.m | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/toolbox/forward/bst_headmodeler.m b/toolbox/forward/bst_headmodeler.m
index 03558fb61..c5137ad70 100644
--- a/toolbox/forward/bst_headmodeler.m
+++ b/toolbox/forward/bst_headmodeler.m
@@ -539,10 +539,11 @@
 %% ===== COMPUTE: SEEG UNIFORM HEADMODELS =====
 if strcmp('uniform', OPTIONS.SEEGMethod)
     Gain(iSeeg, :) =  bst_seeg_uni(OPTIONS.GridLoc, OPTIONS.Channel(iSeeg), sSurfInner, OPTIONS);
-    strHistory =  [strHistory, ' | ', 'Uniform medium (SEEG)',  ' | ', sprintf('Cond: %1.3f', OPTIONS.Conductivity)];
+    strHistory =  [strHistory, ' | ', 'Uniform medium (SEEG)', ...
+                               ' | ', sprintf('Conductivity: %1.3f S/m', OPTIONS.Conductivity), ...
+                               ' | ', sprintf('Min dist. betweem SEEG contact and dipoles: %1.3f mm', OPTIONS.MinSeegDipoleDist)];
 end
 
-
 %% ===== COMPUTE: BRAINSTORM HEADMODELS =====
 Param = [];
 if (~isempty(OPTIONS.MEGMethod) && ~ismember(OPTIONS.MEGMethod, {'openmeeg', 'duneuro'})) || ...

From 19047a083ddeb14acb2c0bbd8f732fe8dc6f23ac Mon Sep 17 00:00:00 2001
From: rcassani <raymundo.cassani@gmail.com>
Date: Tue, 26 May 2026 13:53:41 -0400
Subject: [PATCH 14/16] Update help string `bst_seeg_uni`

---
 toolbox/forward/bst_seeg_uni.m | 48 ++++++++++++++++++++++------------
 1 file changed, 31 insertions(+), 17 deletions(-)

diff --git a/toolbox/forward/bst_seeg_uni.m b/toolbox/forward/bst_seeg_uni.m
index fe198fe99..f9301e99d 100644
--- a/toolbox/forward/bst_seeg_uni.m
+++ b/toolbox/forward/bst_seeg_uni.m
@@ -1,22 +1,22 @@
 function G = bst_seeg_uni(GridLoc, sChannel, sInnerSkull, Options)
-% bst_seeg_uni: Calculate the electric potential, spherical head, arbitrary orientation
+% bst_seeg_uni: Calculate the electric potential for infinite homogeneous medium
 %
-% USAGE:  G = bst_eeg_sph(GridLoc, sChannel, sInnerSkull, Options);
+% USAGE:  G = bst_seeg_uni(GridLoc, sChannel, sInnerSkull, Options)
 %
 % INPUT:
-%    - GridLoc     : dipole location(in meters)    [nDipoles x 3]
-%    - Channel     : a Brainstorm channel structure  [nSensors]  
-%    - sInnerSkull : Inner skull surface
+%    - GridLoc     : Dipole locations (in meters)  [nDipoles x 3]
+%    - sChannel    : Channel structure             [nSensors]
+%    - sInnerSkull : Inner skull surface structure
 %    - Options structure
 %       - Options.Conductivity      : Conductivity (S/m)
 %       - Options.MinSeegDipoleDist : Minimum distance between SEEG and dipoles
 % OUTPUTS:
-%    - G : EEG forward model gain matrix    [nSensors x (3*nDipoles)]
+%    - G : SEEG forward model gain matrix    [nSensors x (3*nDipoles)]
 %
 % DESCRIPTION:  sEEG single layer forward model
 %     This function computes the voltage potential forward gain matrix for an array of 
 %     sEEG electrodes inside the brain. The conductivity is assumed to be uniform and isotropoic
-%     inside the nedium (that is assumed to be infinite).
+%     inside the medium (that is assumed to be infinite).
 %       
 %     For electrodes outside of the brain, the grain is set to 0. 
 % 
@@ -28,6 +28,21 @@
 %          + Næss, S., Halnes, G., Hagen, E., Hagler Jr, D. J., Dale, A. M., Einevoll, G. T., & Ness, T. V. (2021). 
 %            Biophysically detailed forward modeling of the neural origin of EEG and MEG signals. NeuroImage, 225, 117467.  
 %           
+%                 dot(n_i, u_ij)
+%     V(E_j) = --------------------------
+%              4 * pi * sigma0 * (r_ij)^2
+%
+%     V(E_j) = Electric potential at sensor j
+%     n_i    = Vector, current dipole for source i
+%     u_ij   = Unit vector, oriented from source i to sensor j
+%     sigma0 = Conductivity of infinite homogeneous medium
+%     r_ij   = Euclidean distance between source i and sensor j
+%
+%     Written as matrix multiplication:  V = G * N
+%     V = Electric potential at contacts [nSensors, nTime]
+%     G = Gain matrix                    [nSensors, nDipoles]
+%     N = Dipole activation currents     [nDipoles, nTime]
+%
 
 % @=============================================================================
 % This function is part of the Brainstorm software:
@@ -47,7 +62,7 @@
 % For more information type "brainstorm license" at command prompt.
 % =============================================================================@
 %
-% Authors: Edouard Delaire (2026)
+% Authors: Edouard Delaire, 2026
 
     % Add default options
     Options = struct_copy_fields(struct('Conductivity', 0.25, 'MinSeegDipoleDist', 3/1000), Options, 1);
@@ -64,26 +79,25 @@
     % Compute the leadfield
     bst_progress('start', 'Computing head model', sprintf('Computing head model for %d contacts...', NbElectrodes), 0, NbElectrodes);
     G = zeros(NbElectrodes , 3*NbVertices);
-    for iContact =  1:NbElectrodes
-        
+    for iContact = 1:NbElectrodes
+        % Ignore contacts outside of the inner skull
         if ~isSEEGInsideSkull(iContact)
             continue
         end
 
-        VectorDipolesToSEEG =  SEEG_Loc(iContact, :) - GridLoc;
-        DistanceToDipoles = vecnorm(VectorDipolesToSEEG, 2, 2);
-
-        % Normalize the vector
+        % Compute unit vectors from SEEG contact to source points (u_j)
+        VectorDipolesToSEEG = SEEG_Loc(iContact, :) - GridLoc;
+        DistanceToDipoles = sqrt(sum(VectorDipolesToSEEG.^2,2));
         VectorDipolesToSEEG = VectorDipolesToSEEG ./ repmat(DistanceToDipoles, 1, 3);
 
         % Filter short distance
-        iShort =  find(DistanceToDipoles < min_distance);
+        iShort = find(DistanceToDipoles < min_distance);
         if ~isempty(iShort)
             fprintf(' %d vertex had distance to the cortex smaller than %.2f mm to electrodes %s \n', length(iShort), min_distance*1000, sChannel(iContact).Name);           
-            DistanceToDipoles(iShort) =  min_distance;
+            DistanceToDipoles(iShort) = min_distance;
         end
 
-        % Compute the leadfield
+        % Compute the leadfield (u_j / (r_j)^2)
         scaledVector = VectorDipolesToSEEG ./ repmat(DistanceToDipoles.^2, 1, 3); 
 
         % Organize the matrix as x,y,z

From e9285289645879d0c02a2a29786459e2564b003f Mon Sep 17 00:00:00 2001
From: rcassani <raymundo.cassani@gmail.com>
Date: Wed, 27 May 2026 11:44:59 -0400
Subject: [PATCH 15/16] Rename `uniform` to `homogeneous`

---
 toolbox/forward/bst_headmodeler.m               | 17 +++++++++++------
 .../{bst_seeg_uni.m => bst_seeg_homogeneous.m}  |  6 +++---
 toolbox/forward/panel_headmodel.m               | 12 ++++++------
 3 files changed, 20 insertions(+), 15 deletions(-)
 rename toolbox/forward/{bst_seeg_uni.m => bst_seeg_homogeneous.m} (95%)

diff --git a/toolbox/forward/bst_headmodeler.m b/toolbox/forward/bst_headmodeler.m
index c5137ad70..9af1a6298 100644
--- a/toolbox/forward/bst_headmodeler.m
+++ b/toolbox/forward/bst_headmodeler.m
@@ -22,8 +22,13 @@
 %     .EEGMethod:  Method used to compute the forward model for EEG sensors.
 %         - 'eeg_3sphereberg' : EEG forward modeling with a set of 3 concentric spheres (Scalp, Skull, Brain/CSF) 
 %         - 'openmeeg'        : OpenMEEG forward model
-%     .SEEGMethod:    'uniform', 'openmeeg' and 'duneuro'  
-%     .ECOGMethod:    'openmeeg' and 'duneuro' 
+%     .SEEGMethod: Method used to compute the forward model for SEEG sensors.
+%         - 'homogeneous' : Infinite homogeneous medium
+%         - 'openmeeg'    : OpenMEEG forward model
+%         - 'duneuro'     : DUNEuro forward model
+%     .ECOGMethod: Method used to compute the forward model for ECOG sensors.
+%         - 'openmeeg'    : OpenMEEG forward model
+%         - 'duneuro'     : DUNEuro forward model
 %     .NIRSMethod:    'import'
 %
 %     ======= METHODS OPTIONS =============================================
@@ -536,10 +541,10 @@
     Gain(~isnan(Gain_dn)) = Gain_dn(~isnan(Gain_dn));
 end
 
-%% ===== COMPUTE: SEEG UNIFORM HEADMODELS =====
-if strcmp('uniform', OPTIONS.SEEGMethod)
-    Gain(iSeeg, :) =  bst_seeg_uni(OPTIONS.GridLoc, OPTIONS.Channel(iSeeg), sSurfInner, OPTIONS);
-    strHistory =  [strHistory, ' | ', 'Uniform medium (SEEG)', ...
+%% ===== COMPUTE: SEEG INFINITE HOMOGENEOUS MEDIUM HEADMODEL =====
+if strcmp('homogeneous', OPTIONS.SEEGMethod)
+    Gain(iSeeg, :) = bst_seeg_homogeneous(OPTIONS.GridLoc, OPTIONS.Channel(iSeeg), sSurfInner, OPTIONS);
+    strHistory =  [strHistory, ' | ', 'Homogeneous medium (SEEG)', ...
                                ' | ', sprintf('Conductivity: %1.3f S/m', OPTIONS.Conductivity), ...
                                ' | ', sprintf('Min dist. betweem SEEG contact and dipoles: %1.3f mm', OPTIONS.MinSeegDipoleDist)];
 end
diff --git a/toolbox/forward/bst_seeg_uni.m b/toolbox/forward/bst_seeg_homogeneous.m
similarity index 95%
rename from toolbox/forward/bst_seeg_uni.m
rename to toolbox/forward/bst_seeg_homogeneous.m
index f9301e99d..53aadb534 100644
--- a/toolbox/forward/bst_seeg_uni.m
+++ b/toolbox/forward/bst_seeg_homogeneous.m
@@ -1,7 +1,7 @@
-function G = bst_seeg_uni(GridLoc, sChannel, sInnerSkull, Options)
-% bst_seeg_uni: Calculate the electric potential for infinite homogeneous medium
+function G = bst_seeg_homogeneous(GridLoc, sChannel, sInnerSkull, Options)
+% bst_seeg_homogeneous: Calculate the electric potential for infinite homogeneous medium
 %
-% USAGE:  G = bst_seeg_uni(GridLoc, sChannel, sInnerSkull, Options)
+% USAGE:  G = bst_seeg_homogeneous(GridLoc, sChannel, sInnerSkull, Options)
 %
 % INPUT:
 %    - GridLoc     : Dipole locations (in meters)  [nDipoles x 3]
diff --git a/toolbox/forward/panel_headmodel.m b/toolbox/forward/panel_headmodel.m
index 38c7c767d..d70ad294c 100644
--- a/toolbox/forward/panel_headmodel.m
+++ b/toolbox/forward/panel_headmodel.m
@@ -121,7 +121,7 @@
         jCheckMethodSEEG.setSelected(1);
         % Combobox
         jComboMethodSEEG = gui_component('ComboBox', jPanelMethod, 'tab hfill', [], [], [], @UpdateComment, []);
-        jComboMethodSEEG.addItem(BstListItem('uniform', '', 'Uniform medium', []));
+        jComboMethodSEEG.addItem(BstListItem('homogeneous', '', 'Homogeneous medium', []));
         jComboMethodSEEG.addItem(BstListItem('openmeeg', '', 'OpenMEEG BEM', []));
         jComboMethodSEEG.addItem(BstListItem('duneuro', '', 'DUNEuro FEM', []));
         jComboMethodSEEG.setSelectedIndex(0);
@@ -438,7 +438,7 @@ function UpdateComment(varargin)
         sMethod.Comment = strrep(sMethod.Comment, 'os_meg',          'Overlapping spheres');
         sMethod.Comment = strrep(sMethod.Comment, 'meg_sphere',      'Single sphere');
         sMethod.Comment = strrep(sMethod.Comment, 'eeg_3sphereberg', '3-shell sphere');
-        sMethod.Comment = strrep(sMethod.Comment, 'uniform',         'Uniform medium');
+        sMethod.Comment = strrep(sMethod.Comment, 'homogeneous',     'Homogeneous medium');
         sMethod.Comment = strrep(sMethod.Comment, 'openmeeg',        'OpenMEEG BEM');
         sMethod.Comment = strrep(sMethod.Comment, 'duneuro',         'DUNEuro FEM');
         % Grid type
@@ -448,7 +448,7 @@ function UpdateComment(varargin)
             sMethod.Comment = [sMethod.Comment ' (mixed)'];
         end
     end
-    isUniform = any(strcmpi(allMethods, 'uniform'));
+    isHomogeneous = any(strcmpi(allMethods, 'homogeneous'));
     isOpenMEEG = any(strcmpi(allMethods, 'openmeeg'));
     isDuneuro = any(strcmpi(allMethods, 'duneuro'));
     % Get protocol description
@@ -601,9 +601,9 @@ function UpdateComment(varargin)
             return
         end
 
-        % ===== UNIFORM =====
-        if isUniform
-            % Interactive interface to set the OpenMEEG options
+        % ===== INFINITE HOMOGENEOUS MEDIUM =====
+        if isHomogeneous
+            % Interactive interface to set the options
             if OPTIONS.Interactive
                 OPTIONS.Conductivity = [];
                 OPTIONS.MinSeegDipoleDist  = [];

From 489b56d7f7a27d524786e289e4eec968cf3d0b58 Mon Sep 17 00:00:00 2001
From: Raymundo Cassani <raymundo.cassani@gmail.com>
Date: Wed, 27 May 2026 13:15:16 -0400
Subject: [PATCH 16/16] Add comment explaining dist replacement, remove msg

---
 toolbox/forward/bst_seeg_homogeneous.m | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/toolbox/forward/bst_seeg_homogeneous.m b/toolbox/forward/bst_seeg_homogeneous.m
index 53aadb534..c56ecf56f 100644
--- a/toolbox/forward/bst_seeg_homogeneous.m
+++ b/toolbox/forward/bst_seeg_homogeneous.m
@@ -90,10 +90,10 @@
         DistanceToDipoles = sqrt(sum(VectorDipolesToSEEG.^2,2));
         VectorDipolesToSEEG = VectorDipolesToSEEG ./ repmat(DistanceToDipoles, 1, 3);
 
-        % Filter short distance
+        % Replace short distance (< 'min_distance') with 'min_distance' to prevent instabilities in the model by too close measurements
         iShort = find(DistanceToDipoles < min_distance);
         if ~isempty(iShort)
-            fprintf(' %d vertex had distance to the cortex smaller than %.2f mm to electrodes %s \n', length(iShort), min_distance*1000, sChannel(iContact).Name);           
+            % fprintf(' %d vertex had distance to the cortex smaller than %.2f mm to electrodes %s \n', length(iShort), min_distance*1000, sChannel(iContact).Name);           
             DistanceToDipoles(iShort) = min_distance;
         end
 
@@ -110,4 +110,4 @@
     G = G / (4 * pi * sigma0);
 
     bst_progress('stop');
-end
\ No newline at end of file
+end