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+This is BibTeX, Version 0.99d (TeX Live 2017/Debian)
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@@ -140,11 +140,13 @@ Außerdem erkläre ich, dass die eingereichte Arbeit weder vollständig noch in
 \end{enumerate}
 \newpage
 
-The environment of an organism holds important information that it needs to survive, react to predators and find food or mates. That means that the ability to sense and process this information is of vital importance for any organism. At the same time the environment also contains a lot of information that is irrelevant to an organism, as such the sensory systems of an organism need to be specialized to extract the information it needs while filtering out the noise and irrelevant information \todo{ref}.
+The environment of an organism holds important information that it needs to survive. Information about predators to avoid, food to find and potential mates. That means that the ability to sense and process this information is of vital importance for any organism. At the same time the environment also contains a lot of information that is irrelevant to an organism, as such the sensory systems of an organism need to be specialized to extract the information it needs while filtering out the noise and irrelevant information \todo{ref}.
+
+The electric fish \AptLepto (Brown ghost knife fish) generate a sinusoidal electric field with the electric organ in their tail enabling them to use active electroreception which they use to find prey, orient themself and communicate with each other \todo{ref}. The different use cases of this electric organ discharge (EOD) come with the necessity to detect a wide range of different amplitude modulations (AMs). Electrolocation of object in the surrounding water like small prey or rocks cause small low frequency AMs \todo{ref}. At the same time other electric fish can cause stronger and higher frequency AMs through interference between the electric fields and their communication signals like chirps, short increases in their EOD frequency \todo{ref}. This means that the electroreceptors need to be able to encode a wide range of changes in EOD amplitude, in speed as well as strength.
+The EOD and its AMs are encoded by electroreceptor organs in the skin. \lepto have two anatomically different kinds of tuberous electrosensory organs: the T and P type units \todo{ref, Zakon 1993}. The T units (time coder) are strongly phase locked to the EOD and fire regularly once every EOD period. They encode the phase of the EOD in their spike timing \todo{ref}. The P units (probability coders) on the other hand do not fire every EOD period. Instead they fire irregularly with a certain probability that depends on the EOD amplitude \todo{ref}. That way they encode information about the EOD amplitude in their firing probability \todo{ref}. An example of the firing behavior of a P unit is shown in figure~\ref{fig:p_unit_example}. 
+When the fish's EOD is unperturbed P units, it fires every few EOD periods but has a certain variability in its firing (fig. \ref{fig:p_unit_example} B) and show negative correlation between successive interspike intervals (ISIs). When presented with a step change in EOD amplitude P units show strong adaption behavior. After a strong increase in firing rate reacting to the onset of the step, the firing rate quickly decays back to a steady state (fig. \ref{fig:p_unit_example} D). 
+
 
-The electric fish \AptLepto (Brown ghost knife fish) generate a sinusoidal electric field with the electric organ in their tail, which they use to find prey, orientation and communication. The different use cases of this electric organ discharge (EOD) come with the necessity to detect small slow amplitude modulations (AMs) in their electric field to detect small prey like insect larvae while also coding for much stronger and faster AMs caused by the EODs of other electric fish in the area. The EOD and changes in it are encoded by electroreceptor organs in the skin. \lepto have two anatomically different kinds of tuberous electrosensory organs: the T and P type units \todo{ref, Zakon 1993}. Both types encode changes are strongly phase locked to the EOD. The T units (time coder) are more strongly locked to the EOD and fire regularly once every EOD period. They encode the phase of the EOD in their spike timing \todo{ref}. The P units (probability coders) on the other hand do not fire every EOD period instead they fire irregularly with a certain probability that depends on the EOD amplitude \todo{ref}. That way they encode information about the EOD amplitude in their firing probability \todo{ref}. An example of the firing behavior of a P unit is shown in figure~\ref{fig:p_unit_example}. An explanation how the different characteristics were computed is below. \todo{description of the full figure?}
-%The calculation for the different characteristics is explained below. It shows in A a piece of the intracellular voltage recording in the axon of the P unit. In B the firing probability and the phase locking is visualized as the histogram over the interspike intervals (ISIs) and C \todo{...}
-P units show strong adaption behavior to changes in EOD amplitude. After an increase in EOD frequency the firing rate increases strongly and then decays back to a steady state  
 
 
 
@@ -154,11 +156,13 @@ P units show strong adaption behavior to changes in EOD amplitude. After an incr
 
 \begin{figure}[H]
 {\caption{\label{fig:p_unit_example} Example behavior of a p-unit with a high baseline firing rate and an EODf of 744\,Hz. \textbf{A}: A 100\,ms voltage trace of the baseline recording with spikes marked by the black lines. \textbf{B}: The histogram of the ISI with the x-axis in EOD periods, showing the phase locking of the firing. \textbf{C}: The serial correlation of the ISI showing a negative correlation for lags one and two. \textbf{D}: The response of the p-unit to a step increase in EOD amplitude. In \todo{color} the averaged frequency over 10 trials. The p-unit strongly reacts to the onset of the stimulus but very quickly adapts to the new stimulus and then shows a steady state response. \textbf{E}: The fi-curve visualizes the onset and steady-state response of the neuron for different step sizes (contrasts). In \todo{color} the detected onset responses and the fitted Boltzmann, in \todo{color} the detected steady-state response and the linear fit.}}
-{\includegraphics[width=0.9\textwidth]{figures/p_unit_example.png}}
+{\includegraphics[width=1\textwidth]{figures/p_unit_example.png}}
 \end{figure}
+\newpage
 
+\todo{fig: example of ISI differences}
 
-
+\todo{population coding}
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