diff --git a/projects/project_adaptation_fit/adaptation_fit.tex b/projects/project_adaptation_fit/adaptation_fit.tex
index 1f803a2..53de3a1 100644
--- a/projects/project_adaptation_fit/adaptation_fit.tex
+++ b/projects/project_adaptation_fit/adaptation_fit.tex
@@ -8,19 +8,17 @@
 \begin{document}
 
 \input{../instructions.tex}
-
+Sensory adaptation is a process that results in a reduced sensitivity of the sensory system to a stimulus. One of the best known examples might be the light adaptation of the eye to constant illumination. The light adaptation that we all know depends on a multitude of processes that regulate the eye sensitivity. Adaptation is not limited to the visual system but is observed even in the responses of individual neurons.  
 Stimulating a neuron with a constant stimulus for an extended period
-of time often results in a decay of an initially strong response. This
-process is called adaptation. Your task here is to estimate the
-time-constant of the firing-rate adaptation in P-unit electroreceptors
-of the weakly electric fish \textit{Apteronotus leptorhynchus}.
+of time often results in a decay of an initially strong response. Your task here is to analyze the spike-frequency adaptation observed in the p-type electroreceptor afferents (aka. P-units) in the electrosensory periphery of the 
+of the weakly electric fish \textit{Apteronotus leptorhynchus}. P-units are driven by the fish's own electric field and changes of field's amplitude leads to a modulation of the cell's firing rate. Extended stimulation with an increased field amplitude allows to observe the exponentially decaying firing rate. While the light adaptation of the human eye is relatively slow, the firing rate adaptation observed in P-units is quite fast. It is your task to estimate how fast it is.
 
 \begin{questions}
   \question In the accompanying datasets you find the
   \textit{spike\_times} of an P-unit electroreceptor to a stimulus of
   a certain intensity, i.e. the \textit{contrast} which is also stored
   in the file. The contrast of the stimulus is a measure relative to
-  the amplitude of fish's field and is given in percent. The data is sampled
+  the amplitude of fish's own field amplitude and is given in percent. The data is sampled
   with 20\,kHz sampling frequency and spike times are given in
   milliseconds (not seconds!) relative to stimulus onset.
   \begin{parts}
diff --git a/projects/project_photoreceptor/photoreceptor.tex b/projects/project_photoreceptor/photoreceptor.tex
index c31c05d..72413c5 100644
--- a/projects/project_photoreceptor/photoreceptor.tex
+++ b/projects/project_photoreceptor/photoreceptor.tex
@@ -12,14 +12,14 @@
 
 %%%%%%%%%%%%%% Questions %%%%%%%%%%%%%%%%%%%%%%%%%
 \section*{Light responses of an insect photoreceptor.}
-Fly R\,1--6 photoreceptors respond to light-on stimuli with graded membrane
+Insect R\,1--6 photoreceptors respond to light-on stimuli with graded membrane
 potential changes. In the acompanying datasets you find the membrane
-potential of a single R\,1-6 photoreceptor that was recorded while the receptor was
+potential of a single R\,1-6 photoreceptor from the fly \textit{Calliphora vicina}. The receptor was
 stimulated with a light stimulus of different amplitudes.
 
 \begin{questions}
   \question{} The accompanying dataset (photoreceptor\_data.zip)
-  contains seven mat files. Each of these holds the data from one
+  contains seven mat files. Each of these holds the data recorded with one
   stimulus intensity and contains three variables. (i)
   \textit{voltage} a matrix with the recorded membrane potential from
   10 consecutive trials, (ii) \textit{time} a matrix with the