Retrosplenial cortex

Source: Wikipedia, the free encyclopedia.
Retrosplenial cortex
Medial surface of the brain with Brodmann's areas numbered.
Details
Identifiers
Latinregio retrosplenialis
NeuroNames2436, 1802
Anatomical terms of neuroanatomy

The retrosplenial cortex (RSC) is a

splenium of the corpus callosum in primates, although in rodents it is located more towards the brain surface and is relatively larger. Its function is currently not well understood, but its location close to visual areas and also to the hippocampal spatial/memory system suggest it may have a role in mediating between perceptual and memory functions,[2] particularly in the spatial domain.[3] However, its exact contribution to either space or memory processing has been hard to pin down.[4]

Anatomy

There is large variation in the region's size across different species. In humans it comprises roughly 0.3% of the entire cortical surface whereas in rabbits it is at least 10%[5] and in rats it extends for more than half the cerebrum dorso-ventrally, making it one of the largest cortical regions.[2]

On the basis of its microscopic cellular structure it is divided into dysgranular (area 30) and granular (area 29) regions.

anterior thalamic nuclei and the hippocampus.[6]

Neurophysiology

Neurophysiological studies of retrosplenial cortex have mainly been done in rats. Early work showed that around 8.5% of neurons in the retrosplenial cortex are

head direction cells while other neurons have correlated with movement parameters such as spatial location and running speed.[7][8] Recent studies have shown that retrosplenial neuronal activity reflects multiple parameters simultaneously including which environment the animal is currently in,[9] its spatial position in the environment,[10][9] its current head direction and running speed,[9] as well as whether the animal is turning[10] or plans to turn in the future.[11] Many of these features of retrosplenial neurophysiology develop slowly as the animal learns to navigate within an environment,[11] consistent with the idea that the retrosplenial cortex participates in the long-term storage of spatial memory.[12]

Function

In humans,

fMRI studies implicate the retrosplenial cortex in a wide range of cognitive functions including episodic memory, navigation, imagining future events and processing scenes more generally.[2][13] Rodent studies suggest the region is important for using surrounding visual cues to carry out these tasks.[12][14][15][16] Retrosplenial cortex is particularly responsive to permanent, non-moving environmental landmarks[17][18] and is also implicated in using them to make spatial judgements.[19][20]

It has also been suggested that retrosplenial cortex may translate between egocentric (self-centred) and allocentric (world-centred) spatial information, based upon its anatomical location between the hippocampus (where there are allocentric place cell representations) and the parietal lobe (which integrates egocentric sensory information).[12][21][22]

Competitors in the

fMRI activation in their retrosplenial cortex than normal controls when doing so.[23] This is thought to be due to their use of a spatial learning strategy or mnemonic device known as the method of loci
.

The region also displays slow-wave

theta rhythmicity[24] and when people retrieve autobiographical memories, there is theta band interaction between the retrosplenial cortex and the medial temporal lobe.[25]

Pathology

The retrosplenial cortex is one of several brain areas that produces both an anterograde and retrograde amnesia when damaged.[26] People with lesions involving the retrosplenial cortex also display a form of topographical disorientation whereby they can recognise and identify environmental landmarks, but are unable to use them to orientate themselves.[2]

The retrosplenial cortex is one of the first regions to undergo pathological changes in Alzheimer's disease and its prodromal phase of mild cognitive impairment.[27][28][29] There are also experimental findings showing that layer 5 of the retrosplenial cortex is likely responsible for dissociative states of consciousness in mammals.[30]

Gallery

References

  1. ^
    S2CID 25585934
    .
  2. ^
    S2CID 9774642
    .
  3. PMID 30221204
    .
  4. S2CID 9774642
    .
  5. ISBN 978-0-387-26919-1.{{cite book}}: CS1 maint: multiple names: authors list (link
    )
  6. PMID 21847380
    .
  7. S2CID 25125371
    .
  8. PMID 11256450
    .
  9. ^
    PMID 33386396
    .
  10. ^
    S2CID 13211352
    .
  11. ^
    PMID 31178316
    .
  12. ^
    PMID 25140141
    .
  13. S2CID 2069491
    .
  14. S2CID 24868413
    .
  15. PMID 24912150
    .
  16. PMID 21982585
    .
  17. PMID 22912894
    .
  18. PMID 24012136
    .
  19. S2CID 15743957
    .
  20. S2CID 23546010
    .
  21. PMID 17500630
    .
  22. PMID 25282616
    .
  23. S2CID 13921255
    .
  24. S2CID 22294467
    .
  25. PMID 23785155
    .
  26. PMID 3427404
    .
  27. S2CID 34598530
    .
  28. PMID 22783190
    .
  29. S2CID 45735133
    .
  30. S2CID 221769346
    .
Wikimedia Commons has media related to Retrosplenial cortex.
Retrieved from "https://en.wikipedia.org/w/index.php?title=Retrosplenial_cortex&oldid=1208727673"