Jeff reviews Navigating with grid and place cells in cluttered environments today at 10:15AM PDT.
Are patients without EC/HC able to navigate in cluttered environments?
Do they show any impairment at all in this performance task?
I don’t recall this being brought up in any of the papers I have read on these cases.
This points to problems trying to localize these functions in the EC/HC complex.
Another paper we were suggested from the author:
I asked this during the meeting, but I can’t find it now. It in the last 1/4 of the video. The answer was yes. If I can find it I’ll post the time.
Hmmm, yes, memory portions of the tasks but not spatial processing otherwise. You have to be very careful to look at the task to see what it is they are testing.
“The findings suggest that the hippocampus is not needed to carry out the spatial computations needed for map reading and navigating from maps.”
I recall many other papers and videos where they patient was walking (in labs, inside houses, and outdoors) and had no problems in normal navigation as long as the task did not require memorizing the details of navigation.
One question I have is the paper seems to model how a rat behaves in a stable environment, but what happens if the environment is continuously changing? Typically, an environment is in constant flux, but that change is not random. It seems to me that a higher order process similar to Subutai’s comments in the video is needed; otherwise I imagine its possible to contrive a slow oscillating trap in which the model gets stuck even though there is a simple higher order process which would illuminate a better alternative.