diff --git a/CMakeLists.txt b/CMakeLists.txt
index 71a5d5e..553445b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -17,6 +17,7 @@ set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
 find_package(QT NAMES Qt5 REQUIRED COMPONENTS Core)
 find_package(Qt5 REQUIRED COMPONENTS Gui Widgets)
+find_package(OpenMP)
 
 add_executable(samplebrain WIN32 MACOSX_BUNDLE
     app/MainWindow.cpp app/MainWindow.h
@@ -64,6 +65,11 @@ target_link_libraries(samplebrain PRIVATE
     sndfile
 )
 
+if(OpenMP_CXX_FOUND)
+    target_link_libraries(samplebrain PUBLIC OpenMP::OpenMP_CXX)
+endif()
+
+
 # Resources:
 set(samplebrain_resource_files
     "app/images/at.png"
diff --git a/brain/src/brain.cpp b/brain/src/brain.cpp
index 73af15d..7426232 100644
--- a/brain/src/brain.cpp
+++ b/brain/src/brain.cpp
@@ -16,6 +16,7 @@
 
 #include <iostream>
 #include <algorithm>
+#include <atomic>
 #include <sndfile.h>
 #include <float.h>
 #include <spiralcore/audio.h>
@@ -245,10 +246,12 @@ void brain::build_synapses_thresh(search_params &params, double thresh) {
   m_average_error = calc_average_diff(params)*thresh;
   double err = m_average_error*thresh;
   u32 brain_size = m_blocks.size();
-  u32 outer_index = 0;
-  for (auto &i : m_blocks) {
+  std::atomic<u32> progress{0};
+  #pragma omp parallel for
+  for (u32 outer_index = 0; outer_index < brain_size; ++outer_index) {
+    auto &i = m_blocks[outer_index];
     u32 index = 0;
-    status::update("building synapses %d%%",(int)(outer_index/(float)brain_size*100));
+    status::update("building synapses %d%%",(int)(progress/(float)brain_size*100));
     for (auto &j : m_blocks) {
       if (index!=outer_index) {
         // collect connections that are under threshold in closeness
@@ -259,7 +262,7 @@ void brain::build_synapses_thresh(search_params &params, double thresh) {
       }
       ++index;
     }
-    ++outer_index;
+    ++progress;
   }  
 }
 */
@@ -267,23 +270,25 @@ void brain::build_synapses_thresh(search_params &params, double thresh) {
 void brain::build_synapses_fixed(search_params &params) {
   //m_average_error = calc_average_diff(params)*thresh;
   u32 brain_size = m_blocks.size();
-  u32 outer_index = 0;
   u32 num_synapses = NUM_FIXED_SYNAPSES;
   if (num_synapses>=m_blocks.size()) num_synapses=m_blocks.size()-1;
 
   // need to stop the progress updates flooding osc
   u32 update_period = 100;
-  u32 update_tick = 0;
-
-  for (auto &i:m_blocks) {
+  std::atomic<u32> update_tick{0};
+  std::atomic<u32> progress{0};
+  #pragma omp parallel for
+  for (u32 outer_index = 0; outer_index < brain_size; ++outer_index) {
+    auto &i = m_blocks[outer_index];
     if (update_tick>update_period) {
-      status::update("building synapses %d%%",(int)(outer_index/(float)brain_size*100));     
+      status::update("building synapses %d%%",(int)(progress/(float)brain_size*100));
       update_tick=0;
     }
     update_tick++;
  
     u32 index = 0;
     vector<pair<u32,double>> collect;
+    collect.reserve(brain_size);
 
     // collect comparisons to all other blocks
     for (auto &j:m_blocks) {
@@ -308,7 +313,7 @@ void brain::build_synapses_fixed(search_params &params) {
       i.get_synapse().push_back(collect[n].first);
     }
 
-    ++outer_index;
+    ++progress;
   }
   status::update("Done: %d synapses grown for %d blocks",num_synapses*brain_size,brain_size);
 }