Thread by @hugospiers

Just published 3rd in a trilogy of #spierslab reviews (pandemic years) each exploring brain regions in navigation:
2020: #Striatum & #Hippocampus (wth @cgahnstrom)
2021 #Prefrontal Cortex (wth @ZitaPatai)
2022 #HippocampalFormation (wth @NilsNyberg_ @ElDuvelle @caswellcaswell)
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Our latest 2022 review "Spatial goal coding in the hippocampal formation" explores how the hippocampal formation (e.g. hippocampus, subiculum, entorhinal cortex) might code information for navigational guidance. Current #OA version available here: sciencedirect.com/science/articl…

The 1st author of our review @NilsNyberg_ did an amazing job thoroughly reviewing the literature. Its the most detailed review I've ever had the chance to write. Kudos to @NeuroCellPress for supporting such in depth reviews, allowing 310 references!

Nils and I were blessed to have @ElDuvelle and @caswellcaswell as co-authors to dissect the literature on goal coding, replay and computational models.

So what did we find...?
There has been a large number of studies examining this topic in the last 5 years or so. Despite so many exciting discoveries the mechanisms of mammalian navigational goal coding are still somewhat unclear. Our figs highlight some key studies and concepts

Important to consider different types of navigation and metrics that can be coded. Fig 1:

Current standard model of spatial coding in the hippocampal formation (Fig 2)

Hippocampal replay can reflect both the future and non-future goal route (Fig 3):
Illustrations of key studies from Foster Lab (A) and van der Meer Lab (B):

We were keen to integrate human studies with the rodent work. Here we summarise evidence for spatial goal coding in the human brain (Fig 4):

Past 🐁 &🦇 studies have provided some evidence of distance and direction to goal modulation in single unit activity in the hippocampus (Fig 5):

Summary of key finding of goal-shifting activity in hippocampal place cells by Dupret et al. 2010 (Fig 6):

So what might all this mean? Here in Fig 7 we summarise what evidence suggests may be going on in different subregions of the hippocampal formation:

How do different computational models fair?
See this table devised by @caswellcaswell :

See page 5 of our PDF: reader.elsevier.com/reader/sd/pii/…

See excellent thread from @NilsNyberg_ on our article:

https://twitter.com/NilsNyberg_/status/1482313032323719168?s=20