Parahippocampal gyrus

From Infogalactic: the planetary knowledge core
Jump to: navigation, search
Parahippocampal gyrus
File:Sobo 1909 630 - Parahippocampal gyrus.png
Human brain seen from below. Parahippocampal gyrus shown in blue
Cerebral Gyri - Medial Surface2.png
Medial view of left cerebral hemisphere. Parahippocampal gyrus shown in orange.
Details
Latin gyrus parahippocampalis
Identifiers
MeSH A08.186.211.577.710
NeuroLex ID Parahippocampal gyrus
Dorlands
/Elsevier
g_13/14816442
TA Lua error in Module:Wikidata at line 744: attempt to index field 'wikibase' (a nil value).
TH {{#property:P1694}}
TE {{#property:P1693}}
FMA {{#property:P1402}}
Anatomical terminology
[[[d:Lua error in Module:Wikidata at line 863: attempt to index field 'wikibase' (a nil value).|edit on Wikidata]]]

The parahippocampal gyrus (Syn. hippocampal gyrus)[1] is a grey matter cortical region of the brain that surrounds the hippocampus and is part of the limbic system. This region plays an important role in memory encoding and retrieval.

It has been involved in some cases of hippocampal sclerosis.[2]

Asymmetry has been observed in schizophrenia.[3]

Structure

The anterior part of the gyrus includes the perirhinal and entorhinal cortices[citation needed].

The term parahippocampal cortex is used to refer to an area that encompasses both the posterior parahippocampal gyrus and the medial portion of the fusiform gyrus.

Function

Scene recognition

The parahippocampal place area (PPA) is a sub-region of the parahippocampal cortex that lies medially in the inferior temporo-occipital cortex. PPA plays an important role in the encoding and recognition of environmental scenes (rather than faces). fMRI studies indicate that this region of the brain becomes highly active when human subjects view topographical scene stimuli such as images of landscapes, cityscapes, or rooms (i.e. images of "places"). The region was first described by Russell Epstein (currently at the University of Pennsylvania) and Nancy Kanwisher (currently at MIT) in 1998,[4] see also other similar reports by Geoffrey Aguirre[5][6] and Alumit Ishai.[7]

Damage to the PPA (for example, due to stroke) often leads to a syndrome in which patients cannot visually recognize scenes even though they can recognize the individual objects in the scenes (such as people, furniture, etc.). The PPA is often considered the complement of the fusiform face area (FFA), a nearby cortical region that responds strongly whenever faces are viewed, and that is believed to be important for face recognition.

Social context

Additional research has increased the probability that the right parahippocampal gyrus in particular has functions beyond the contextualizing of visual background. Tests by a California-based group led by Katherine P. Rankin indicate that the lobe may play a crucial role in identifying social context as well, including paralinguistic elements of verbal communication.[8] For example, Rankin's research suggests that the right parahippocampal gyrus enables people to detect sarcasm.

Additional images

References

  1. Reuter P.: Der Grobe Reuter Springer Universalworterbuch Medizin, Pharmakologie Und Zahnmedizin: Englisch-deutsch (Band 2), Birkhäuser, 2005, ISBN 3-540-25102-2, p. 648 here online
  2. Lua error in package.lua at line 80: module 'strict' not found.
  3. Lua error in package.lua at line 80: module 'strict' not found.
  4. Lua error in package.lua at line 80: module 'strict' not found.
  5. Lua error in package.lua at line 80: module 'strict' not found.
  6. Lua error in package.lua at line 80: module 'strict' not found.
  7. Lua error in package.lua at line 80: module 'strict' not found.
  8. Lua error in package.lua at line 80: module 'strict' not found.

External links