# Ephys cell type database and duration of slices being ex-vivo

**URL:** <https://community.brain-map.org/t/ephys-cell-type-database-and-duration-of-slices-being-ex-vivo/574>\
**Category:** Technical\
**Tags:** atlas-cell-types, experiment-design, tissue-process\
**Created:** [May 24, 2020, 12:33am UTC](https://community.brain-map.org/t/ephys-cell-type-database-and-duration-of-slices-being-ex-vivo/574 "2020-05-24T00:33:40Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![MichaelFeyerabend](https://avatars.discourse-cdn.com/v4/letter/m/5f8ce5/32.png) [@MichaelFeyerabend](https://community.brain-map.org/u/MichaelFeyerabend)\
**Post date:** [May 24, 2020, 12:33am UTC](https://community.brain-map.org/t/ephys-cell-type-database-and-duration-of-slices-being-ex-vivo/574/1 "2020-05-24T00:33:40Z")

</div>

Hello everyone,

I would like to look into a possible relationship between time of the slices being ex-vivo and intrinsic features obtained from intracellular recordings. The only time information, I found useful in that context, was in ‘\start\_session\_time’ in the nwb files themselves and more than half of the cells have single capital letters instead of a time stamp, whose meaning I do not understand. I would appreciate if someone could share if this information can be assessed somewhere.

Thank you,

Michael Feyerabend

---

<div class="post-metadata">

**Author:** ![jim](https://yyz1.discourse-cdn.com/flex027/user_avatar/community.brain-map.org/jim/32/206_2.png) [@jim](https://community.brain-map.org/u/jim)\
**Post date:** [June 15, 2020, 8:19pm UTC](https://community.brain-map.org/t/ephys-cell-type-database-and-duration-of-slices-being-ex-vivo/574/2 "2020-06-15T20:19:53Z")

</div>

Hi,

Thanks for writing in. Unfortunately ‘time ex-vivo’ is not currently part of our set of metadata that we include with each recording. It’s good to know that there is interest and I will bring it up as an addition for a future release (and will update here).

Thanks,  
Jim