[projects] checked Jan B and Lukas projects

projects/project_vector_strength/vector_strength.tex

@@ -9,18 +9,18 @@
 
 \input{../instructions.tex}
 
-%%%%%%%%%%%%%% Questions %%%%%%%%%%%%%%%%%%%%%%%%%
-\section*{Quantifying the coupling of action potentials to the EOD.}
-Phase coupling of neuronal activity is observed in several
-system. This means that the action potentials fired by a neuron occur
-with specific phase relation to the driving periodic signal. For example sensory
-neurons in the auditory system and the electrosensory system fire in
-close phase relation to the stimulus frequncy.  P-type electroreceptor
-afferents (P-units) of the weakly electric fish \emph{Apteronotus
-  leptorhynchus} are driven by the fish's self-generated field, the
-EOD and fire action potentials phase locked to it. In this project you
-have to quantify the strength of this coulpling using the
-\textbf{vector strength}:
+Phase coupling of neuronal activity is observed in many systems. This
+means that the action potentials fired by a neuron occur with a
+specific phase relation to a driving periodic signal. For example,
+sensory neurons in auditory systems and electrosensory systems fire in
+close phase relation to the stimulus frequency.  P-type
+electroreceptor afferents (P-units) of the weakly electric fish
+\emph{Apteronotus leptorhynchus} are driven by the fish's
+self-generated field, the electric organ discharge (EOD), and fire
+action potentials phase locked to it.
+
+In this project you quantify the strength of the coupling of P-unit
+spikes to the EOD using the \textbf{vector strength}:
 \begin{equation}
  VS = \sqrt{\left(\frac{1}{n}\sum_{i=1}^{n}\cos
  \alpha_i\right)^2 + \left(\frac{1}{n}\sum_{i = 1}^{n} \sin \alpha_i
@@ -28,27 +28,38 @@ have to quantify the strength of this coulpling using the
 \end{equation}
 with $n$ the number of spikes and $\alpha_i$ the timing of the each
 spike expressed as the phase relative to the EOD. The vector strength
-varies between $0$ and $1$ for no phase locking to perfect phase
-locking, respectively.
+varies between $0$ for no phase locking and $1$ for perfect phase
+locking.
 
 \begin{questions}
   \question In the accompanying datasets you find recordings of the
   ``baseline'' activity of P-unit electroreceptors (in the absence of
   an external stimulus) of different weakly electric fish of the
   species \textit{Apteronotus leptorhynchus}.  The files further
-  contain respective recordings of the \textit{eod}, i.e. the fish's
+  contain respective recordings of the EOD, i.e. the fish's
   electric field. The data is sampled with 20\,kHz and the spike times
   are given in seconds.
   \begin{parts}
-    \part Illustrate the phase locking by plotting the PSTH within the EOD cycle.
+    \part Plot the EOD with the evoked spikes on top.
+    
+    \part Illustrate the phase locking by plotting the PSTH within the
+    EOD cycle.
+    
     \part Implement a function that estimates the vector strength
-    between the \textit{EOD} and the spikes.
+    between the EOD and the spikes.
+    
     \part Create a polar plot that shows the timing of the spikes 
-    relatve to the EOD.
-    \part Apply an appropriate statistical test to check whether locking is statistically significant.
-    \part Analyze the baseline responses of each fish and extract measures as were introduced in chapter 10 of the script. Plot the results
-    appropriately.
-    \part Does the vector strength correlate with the EOD frequency or the reponse variability (CV)?
+    relative to the EOD.
+    
+    \part Apply an appropriate statistical test to check whether
+    locking is statistically significant.
+    
+    \part Analyze the baseline responses of each fish and extract
+    measures as were introduced in chapter 10 of the script. Plot the
+    results appropriately.
+    
+    \part Does the vector strength correlate with the EOD frequency or
+    the reponse variability (CV)?
   \end{parts}
 \end{questions}