You see a rat and a lever.
The rat presses the lever occasionally.
Now you start rewarding the rat:
when it presses the lever it is rewarded with a particular kind of food.
As a consequence, the rat presses the lever more often.
\subsection{Devaluation - standard procedure}
\begin{itemize}
\item Training: Rat is put in chamber with Lever; pressing Lever dispenses sucrose (novel food).
\item Devaluation: Rat is taken into another chamber, poisoned,
and then exposed to sucrose.
\item Extinction Test: Rat returns to chamber with Lever; pressing Lever does nothing.
\end{itemize}
Dickinson, 1985 figure 3; Balleine & Dickinson, 1991 figure 1 (part)
Devaluation - standard procedure:
Training: Rat is put in chamber with Lever; pressing Lever dispenses sucrose (novel food).
Devaluation: Rat is taken into another chamber, poisoned, and then exposed to sucrose.
Extinction Test: Rat returns to chamber with Lever; pressing Lever does nothing.
Dickinson, 1985 figure 3; Balleine & Dickinson, 1991 figure 1 (part)
‘Mean lever-press rates during the extinction (left-hand panel) and reacquisition tests (right-handpanel) followingthe devaluation of either the contingent (group D-N) or non-contingentfood (group N-D).’
‘Experiment I: Mean number of lever presses ... during the extinction test session
...
The various groups received either immediate (Groups IMM/SUC and IMM/ H20) or delayed (Groups DELjSUC and DEL/H2O)
toxicosis [delayed did not cause aversion] and were re-exposed either to the sucrose solution (Groups IMM/SUC and DEL/SUC)
or to water (Groups IMM/H2O and DEL/H20).’
Pavlovain conditioning, primary motivational states can have a direct effect on actions.
