Neuroanatomy of facial processing
editFacial perception has well identified, neuroanatomical correlates in the brain. During the perception of faces, major activations occur in the extrastriate areas bilaterally, particularly in the fusiform face area (FFA), the occipital face area (OFA), and the superior temporal sulcus (fSTS).[1][2]
The FFA is located in the lateral fusiform gyrus. It is thought that this area is involved in holistic processing of faces and it is sensitive to the presence of facial parts as well as the configuration of these parts. The FFA is also necessary for successful face detection and identification. This is supported by fMRI activation and studies on prospagnosia, which involves lesions in the FFA.[1][2][3]
The OFA is located in the inferior occipital gyrus.[2] Similar to the FFA, this area is also active during successful face detection and identification, a finding that is supported by fMRI activation.[1] The OFA is involved and necessary in the analysis of facial parts but not in the spacing or configuration of facial parts. This suggests that the OFA may be involved in a facial processing step that occurs prior to the FFA processing.[1]
The fSTS is involved in recognition of facial parts and is not sensitive to the configuration of these parts. It is also thought that this area is involved in gaze perception.[4] The fSTS has demonstrated increased activation when attending to gaze direction.[1]
Bilateral activation is generally shown in all of these specialized facial areas.[5][6][7][8][9][10] However there are some studies that include increased activation in one side over the other. For instance McCarthy (1997) has shown that the right fusiform gyrus is more important for facial processing in complex situations.[3]
Gorno-Tempini and Price have shown that the fusiform gyri are preferentially responsive to faces, whereas the parahippocampal/lingual gyri are responsive to buildings.[11]
It is important to note that while certain areas respond selectively to faces, facial processing involves many neural networks. These networks include visual and emotional processing systems as well. Emotional face processing research has demonstrated that there are some of the other functions at work. While looking at faces displaying emotions (especially those with fear facial expressions) compared to neutral faces there is increased activity in the right fusiform gyrus. This increased activity also correlates with increased amygdala activity in the same situations.[12] The emotional processing effects observed in the fusiform gyrus are decreased in patients with amygdala lesions [12]. This demonstrates possible connections between the amygdala and facial processing areas.[12]
Another aspect that affects both the fusiform gyrus and the amygdala activation is the familiarity of faces. Having multiple regions that can be activated by similar face components indicates that facial processing is a complex process.[12]
References
edit- ^ a b c d e Liu J, Harris A, Kanwisher N. (2010). Perception of face parts and face configurations: An fmri study. Journal of Cognitive Neuroscience. (1), 203–211.
- ^ a b c Rossion, B., Caldara, R., Seghier, M., Schuller, A-M., Lazeyras, F., Mayer, E., (2003). A network of occipito-temporal face-sensitive areas besides the right middle fusiform gyrus is necessary for normal face processing. A Journal of Neurology, 126 11 2381-2395
- ^ a b McCarthy, G., Puce, A., Gore, J., Allison, T., (1997). Face-Specific Processing in the Human Fusiform Gyrus. Journal of Cognitive Neuroscience, 9 5 605-610
- ^ Campbell, R., Heywood, C.A., Cowey, A., Regard, M., and Landis, T. (1990). Sensitivity to eye gaze in prosopagnosic patients and monkeys with superior temporal sulcus ablation. Neuropsychologia, 28(11), 1123-1142
- ^ ci |volume=8 |issue=2 |pages=139–46 |year=1996 |pmid=9081548|author-separator=,|author2=O'Leary DS|author3=Arndt S|display-authors=3|last4=Cizadlo|first4=T|last5=Hurtig|first5=R|last6=Rezai|first6=K|last7=Watkins|first7=GL|last8=Ponto|first8=LB|last9=Hichwa|first9=RD}}
- ^ Haxby JV, Horwitz B, Ungerleider LG, Maisog JM, Pietrini P, Grady CL (1 November 1994). "The functional organization of human extrastriate cortex: a PET-rCBF study of selective attention to faces and locations". J. Neurosci. 14 (11 Pt 1): 6336–53. doi:10.1523/JNEUROSCI.14-11-06336.1994. PMC 6577268. PMID 7965040.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Haxby JV, Ungerleider LG, Clark VP, Schouten JL, Hoffman EA, Martin A (January 1999). "The effect of face inversion on activity in human neural systems for face and object perception". Neuron. 22 (1): 189–99. doi:10.1016/S0896-6273(00)80690-X. PMID 10027301.
{{cite journal}}: CS1 maint: date and year (link) CS1 maint: multiple names: authors list (link) - ^ Puce A, Allison T, Asgari M, Gore JC, McCarthy G (15 August 1996). "Differential sensitivity of human visual cortex to faces, letterstrings, and textures: a functional magnetic resonance imaging study". J. Neurosci. 16 (16): 5205–15. doi:10.1523/JNEUROSCI.16-16-05205.1996. PMC 6579313. PMID 8756449.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Puce A, Allison T, Gore JC, McCarthy G (September 1995). "Face-sensitive regions in human extrastriate cortex studied by functional MRI". J. Neurophysiol. 74 (3): 1192–9. doi:10.1152/jn.1995.74.3.1192. PMID 7500143.
{{cite journal}}: CS1 maint: date and year (link) CS1 maint: multiple names: authors list (link) - ^ Sergent J, Ohta S, MacDonald B (February 1992). "Functional neuroanatomy of face and object processing. A positron emission tomography study". Brain. 115 (Pt 1): 15–36. doi:10.1093/brain/115.1.15. PMID 1559150.
{{cite journal}}: CS1 maint: date and year (link) CS1 maint: multiple names: authors list (link) - ^ Gorno-Tempini ML, Price CJ (October 2001). "Identification of famous faces and buildings: a functional neuroimaging study of semantically unique items". Brain. 124 (Pt 10): 2087–97. doi:10.1093/brain/124.10.2087. PMID 11571224.
{{cite journal}}: CS1 maint: date and year (link) - ^ a b c d Vuilleumier P, Pourtois G, Distributed and interactive brain mechanisms during emotion face perception: Evidence from functional neuroimaging. Neuropsychologia 45 (2007) 174–194