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Successful decoding of famous faces in the fusiform face area.

Axelrod V, Yovel G - PLoS ONE (2015)

Bottom Line: We found that face-identity could be discriminated above chance level only in the fusiform face area.Our results corroborate the role of the fusiform face area in face recognition.Future studies are needed to further explore the role of the more recently discovered anterior face-selective areas in face recognition.

View Article: PubMed Central - PubMed

Affiliation: School of Psychological Sciences, Tel Aviv University, Tel Aviv, Israel.

ABSTRACT
What are the neural mechanisms of face recognition? It is believed that the network of face-selective areas, which spans the occipital, temporal, and frontal cortices, is important in face recognition. A number of previous studies indeed reported that face identity could be discriminated based on patterns of multivoxel activity in the fusiform face area and the anterior temporal lobe. However, given the difficulty in localizing the face-selective area in the anterior temporal lobe, its role in face recognition is still unknown. Furthermore, previous studies limited their analysis to occipito-temporal regions without testing identity decoding in more anterior face-selective regions, such as the amygdala and prefrontal cortex. In the current high-resolution functional Magnetic Resonance Imaging study, we systematically examined the decoding of the identity of famous faces in the temporo-frontal network of face-selective and adjacent non-face-selective regions. A special focus has been put on the face-area in the anterior temporal lobe, which was reliably localized using an optimized scanning protocol. We found that face-identity could be discriminated above chance level only in the fusiform face area. Our results corroborate the role of the fusiform face area in face recognition. Future studies are needed to further explore the role of the more recently discovered anterior face-selective areas in face recognition.

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Comparison of individual classification rates of identity discrimination in the right FFA for the original (Benjamin Netanyahu and Shimon Peres) experiment and the replication (Leonardo DiCaprio and Brad Pitt).
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pone.0117126.g008: Comparison of individual classification rates of identity discrimination in the right FFA for the original (Benjamin Netanyahu and Shimon Peres) experiment and the replication (Leonardo DiCaprio and Brad Pitt).

Mentions: Replication experiment with a new set of famous faces. The original experiment had two potential limitations related to generalization of the findings. First, the experiment used the same face identities for localization of the face-selective regions and for the face identity discrimination analysis; accordingly, it can be claimed that our discrimination results were specific for the face-selective voxels that were most sensitive to two specific identities. Second, the original experiment included only two face identities. To address both of these shortcomings, we ran the following experiment: a) the face-selective regions were localized using an independent functional localizer with various unfamiliar face and object stimuli (independent set of stimuli); and b) discrimination analysis was conducted for two additional famous face identities (Leonardo DiCaprio and Brad Pitt). The goal of the experiment was to test whether the successful decoding of the famous faces in the right FFA can be replicated using two novel identities. Five participants who participated in the original experiment participated in this experiment. Average fMRI signal and decoding results are shown in Fig. 7. Only ROIs localized in at least three participants are shown. The average fMRI signal for both face identities was similar. Critically, corroborating our findings of the original experiment, the average classification rate between two identities in the right FFA was the high, reaching the level of 60%. Despite the small sample size (N = 5), prediction in the right FFA was significantly beyond chance level (t(4) = 3.96, p = 0.008). In addition, in Fig. 8 we show individual classification rates between face identities in the original and the replication experiment. Critically, in all participants the prediction rate was beyond chance level (50%) for both face pairs. Some prediction rate variability between experiments could be explained by the temporal difference between experiments (about 3.5 years) and potential difference in semantic information associated with two categories (i.e., politicians vs. actors). Taken together the results of the replication experiment demonstrate that the two famous face identities could be discriminated in the right FFA, which was localized using independent functional localization procedure.


Successful decoding of famous faces in the fusiform face area.

Axelrod V, Yovel G - PLoS ONE (2015)

Comparison of individual classification rates of identity discrimination in the right FFA for the original (Benjamin Netanyahu and Shimon Peres) experiment and the replication (Leonardo DiCaprio and Brad Pitt).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4340964&req=5

pone.0117126.g008: Comparison of individual classification rates of identity discrimination in the right FFA for the original (Benjamin Netanyahu and Shimon Peres) experiment and the replication (Leonardo DiCaprio and Brad Pitt).
Mentions: Replication experiment with a new set of famous faces. The original experiment had two potential limitations related to generalization of the findings. First, the experiment used the same face identities for localization of the face-selective regions and for the face identity discrimination analysis; accordingly, it can be claimed that our discrimination results were specific for the face-selective voxels that were most sensitive to two specific identities. Second, the original experiment included only two face identities. To address both of these shortcomings, we ran the following experiment: a) the face-selective regions were localized using an independent functional localizer with various unfamiliar face and object stimuli (independent set of stimuli); and b) discrimination analysis was conducted for two additional famous face identities (Leonardo DiCaprio and Brad Pitt). The goal of the experiment was to test whether the successful decoding of the famous faces in the right FFA can be replicated using two novel identities. Five participants who participated in the original experiment participated in this experiment. Average fMRI signal and decoding results are shown in Fig. 7. Only ROIs localized in at least three participants are shown. The average fMRI signal for both face identities was similar. Critically, corroborating our findings of the original experiment, the average classification rate between two identities in the right FFA was the high, reaching the level of 60%. Despite the small sample size (N = 5), prediction in the right FFA was significantly beyond chance level (t(4) = 3.96, p = 0.008). In addition, in Fig. 8 we show individual classification rates between face identities in the original and the replication experiment. Critically, in all participants the prediction rate was beyond chance level (50%) for both face pairs. Some prediction rate variability between experiments could be explained by the temporal difference between experiments (about 3.5 years) and potential difference in semantic information associated with two categories (i.e., politicians vs. actors). Taken together the results of the replication experiment demonstrate that the two famous face identities could be discriminated in the right FFA, which was localized using independent functional localization procedure.

Bottom Line: We found that face-identity could be discriminated above chance level only in the fusiform face area.Our results corroborate the role of the fusiform face area in face recognition.Future studies are needed to further explore the role of the more recently discovered anterior face-selective areas in face recognition.

View Article: PubMed Central - PubMed

Affiliation: School of Psychological Sciences, Tel Aviv University, Tel Aviv, Israel.

ABSTRACT
What are the neural mechanisms of face recognition? It is believed that the network of face-selective areas, which spans the occipital, temporal, and frontal cortices, is important in face recognition. A number of previous studies indeed reported that face identity could be discriminated based on patterns of multivoxel activity in the fusiform face area and the anterior temporal lobe. However, given the difficulty in localizing the face-selective area in the anterior temporal lobe, its role in face recognition is still unknown. Furthermore, previous studies limited their analysis to occipito-temporal regions without testing identity decoding in more anterior face-selective regions, such as the amygdala and prefrontal cortex. In the current high-resolution functional Magnetic Resonance Imaging study, we systematically examined the decoding of the identity of famous faces in the temporo-frontal network of face-selective and adjacent non-face-selective regions. A special focus has been put on the face-area in the anterior temporal lobe, which was reliably localized using an optimized scanning protocol. We found that face-identity could be discriminated above chance level only in the fusiform face area. Our results corroborate the role of the fusiform face area in face recognition. Future studies are needed to further explore the role of the more recently discovered anterior face-selective areas in face recognition.

Show MeSH