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--- methods:novelobjectrecognition [2023/07/13 18:00] – ohardt
+++ methods:novelobjectrecognition [2023/07/15 15:19] (current) – external edit 127.0.0.1
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 ====== Novel Object Recognition ======
-Like many mammals, rats are attracted to novelty.  In order to recognize something in the environment as novel, there needs to be memory for what has been encountered before.  The relative attention the animal will devote to the novel compared to the familiar in the environment can therefore be used as a proxy for available memory.The novel object recognition task makes use of this effect and is widely employed in memory research, where it is considered a good model for human declarative memory.  With lab- and task-specific optimizations, the task produces robust, reliable results.
+Like many mammals, rats are attracted to novelty.  In order to recognize something in the environment as novel, there needs to be memory for what has been encountered before.  The relative attention the animal will devote to the novel compared to the familiar in the environment can therefore be used as a proxy for available memory. The novel object recognition task makes use of this effect and is widely employed in memory research, where it is considered a good model for human declarative memory.  With lab- and task-specific optimizations, the task produces robust, reliable results.
+This task assesses memory animals have for the identity of a previously encountered object. Identity can be deduced from various sensory inputs received during object exploration.  Yet, the vast majority of rat studies introduces novelty by varying visual characteristics of [[methods:materials:objectlibrary|the objects]].  The stronger the visual differences, the easier it will be to discriminate familiar from novel objects.
 In our lab, the task typically consists of three phases -- Habituation, Sampling, and Probe.
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 All phases are video recorded, and it is good practice that there are no other rats or experimenters in the room in which the open field is placed, as their presence could influence the behaviour of interest.  The videos are then later scored by trained observers.  In our lab, we do not use software (yet) to automatically score rat exploratory behaviour.
-Once the behaviour has been quantified -- i.e., the time animals spend exploring objects has been measured -- the discrimination index DI (or d) is calculated and statistically analyzed.  The index is calculated as follows: DI=[(time exploring novel object)-(time exploring familiar object)]/(time exploring both).  DI can take any value between -1 and 1. DI=0 indicates that both objects were explored the same, i.e., the absence of preference or the behaviour that would be expected by chance alone.  Di>0 indicates that the novel object was explored more than the familiar one, and DI<-0 indicates the opposite.  To determine whether DI is significantly different from what would be expected by chance alone, a one-sample t-test comparing DI against 0 can be used.
+Once the behaviour has been quantified -- i.e., the time animals spend exploring objects has been measured -- the discrimination index DI (or d) is calculated and statistically analyzed.  The index is calculated as follows: DI=[(time exploring novel object)-(time exploring familiar object)]/(time exploring both).  DI can take any value between -1 and 1. DI=0 indicates that both objects were explored the same, i.e., the absence of preference or the behaviour that would be expected by chance alone.  Di>0 indicates that the novel object was explored more than the familiar one, and DI<0 indicates the opposite.  To determine whether DI is significantly different from what would be expected by chance alone, a one-sample t-test comparing DI against 0 can be used.
-Our detailed protocols are available at the SOP seciton.
+Our detailed protocols are available at the SOP section.