hippocampus lecture 2 Flashcards
what is correlation coding
the relation of spike times across different neurons
neural coding
action potentials reflect our sensory perceptions, cognitive functions and behaviour
Rate coding - Orientation
Hubel and Wiesel (1968) - The firing rate of action potentials depends on the orientation of the stimulus
Rate coding- spatial location
Hafting et al (2005 ) spatial location of the rat during action potentials of a neuron in the entorhinal cortex.
Place cells: O’Keefe and Dostrovsky (1971)
Respond soley/ maximally when rat situated in a particular part of the platform in a particular direction
Where are place cells located
The pyramidal neurons in CA3 and CA1 for each cell associated part of the environment- place field.
Nakazawa et al (2004)
rat running along path, activates different place field.
What happens to place field when environment changes?
Place cells can change the location of their place field and firing rate depending on how their environment changes
What is rate remapping
If the rats environment shows a small degree of change place cells show rate remapping.
complete remapping
If the rats environment shows a complete change.
Fyhn et al., (2007)
Simultaneous recordings from hippocampal and entorhinal grid cells.
When hippocampal place cells show rate remapping, grid cells show no change
Complete remapping causes grid cells to show unpredictable shifts and rotations
what is correlation coding?
correlation of two spike trains of neurons where the relation between the spike times of different neurons becomes important.
What are the firing patterns on hippocampal neurons?
Most dominant feature of hippocampal firing is place cells . become active in different locations.
