diff --git a/projects/project_populationvector/populationvector.tex b/projects/project_populationvector/populationvector.tex
index 7b5cb69..4f98614 100644
--- a/projects/project_populationvector/populationvector.tex
+++ b/projects/project_populationvector/populationvector.tex
@@ -13,7 +13,8 @@
 \begin{questions}
 
   \question In the visual cortex V1 orientation sensitive neurons
-  respond to bars in dependence on their orientation.
+  respond to bars in dependence on their orientation. In this project
+  we explore the question:
 
   How is the orientation of a bar encoded by the activity of a
   population of orientation sensitive neurons?
@@ -54,6 +55,8 @@
     position of the peak, $g$ is a gain factor that sets the
     modulation depth of the firing rate, and $a$ is an offset.
 
+    Why is there a factor two in the argument of the cosine?
+
     \part How can the orientation angle of the presented bar be read
     out from one trial of the population activity of the 6 neurons?
     One possible method is the so called ``population vector'' where
@@ -74,6 +77,9 @@
     \texttt{population*.mat} files). How exactly is the orientation of
     the bar encoded? How robust is the estimate of the orientation
     from trial to trial?
+
+    \part Can you think of yet another strategy to estimate the
+    orientation of the bar from the activity of the neurons?
   \end{parts}
 \end{questions}