The neural processing of familiar and unfamiliar faces: A review and synopsis

1. The neural processing of familiar and unfamiliar faces: A review and synopsis VaidehiNatu and Alice J. O’Toole

2. The neural processing of familiar and unfamiliar faces: A review and synopsis • Neural regions implicated in unfamiliar face perception • Neural systems for processing familiar vs. unfamiliar faces • PET • fMRI

3. 1. Neural regions implicated in unfamiliar face perception • fusiform “face” area (FFA) • in the middle of the fusiform gyrus (FG) • face selective area • occipital “face” area (OFA) • inferior occipital gyrus • face selective area • superior temporal gyrus (STS) • specific to dynamic stimuli?

4. 1. Neural regions implicated in unfamiliar face perception Quelle: Wikipedia

5. 1. Neural regions implicated in unfamiliar face perception Quelle: Wikipedia

6. 1. Neural regions implicated in unfamiliar face perception Intraparietal sulcus Spatiallydirectedattention Superior temporal sulcus Changeableaspectsoffaces (perceptionofeyegaze, expressionandlipmovement) Auditorycortex Prelexicalspeechperception Inferior occipitalgyri Early perceptionoffacialfeatures Amygdala, Insula, limbicsystem Emotion Lateral fusiformgyrus Invariant aspectsoffaces – perceptionofuniqueidentity Anterior temporal Personal identity, nameandbiographicalinformation Core System Haxby et al. (2000) Extended System

7. 2. Neural systems for processing familiar vs. unfamiliar faces • personally familiar faces • visualcomponent • representations of the person’s mental state, personality, and the emotions an observer experiences on seeing the face  modulated by relationship • visually familiar faces • learned faces • visual component • famous familiar faces • visual component and semantic long-term memory component

8. 2.1 Neural systems for processing familiar vs. unfamiliar faces (PET) • personally familiar faces • priming effects for personally familiar faces vs. unfamiliar faces • familiarity: amygdala and medial frontal cortex • other: bilateral anterior temporal cortices • visually familiar faces • categorization task & face-recognition task • unfamiliarity: OFA, FFA and amygdala(?) larger activation • famous familiar faces • categorization tasks (e.g. identity, gender etc.), famous vs. non-famous • familiarity: FG, anterior and middle temporal cortex • other: right lingual gyrus, parahippo-campalareas

9. 2.2 Neural systems for processing familiar vs. unfamiliar faces (fMRI) • Famous faces: subtraction studies • simple conditions: • famous vs. unfamiliar faces: bilateral middle temporal, right superior temporal, right hippocampus bilateral superior, and left medial frontal cortex , no activation in FG • visual perception: responses in inferior occipital gyri, FG, STS, and the amygdala • more complex conditions: • incidental task vs. intentional task  incidental task revealed stronger activation in the perirhinal cortex and right parahippocampus (medial temporal lobe) for famous faces

10. 2.2 Neural systems for processing familiar vs. unfamiliar faces (fMRI) • Famous faces: adaptation studies • Are famous and unfamiliar face representations view-(in)dependent? • recognition of unfamiliar faces is disrupted with viewpoint change, whereas recognition of familiar faces is not • the FFA adapts to repeated presentations of the same unfamiliar identity, but recovers when the viewpoint of the face is changed • FFA is involved in the view-dependent processing of faces, regardless of familiarity (image-independent face representations are maybe anterior to image-dependent representations along the FG) • view-invariant famous face representations: temporal and frontal cortex

11. 2.2 Neural systems for processing familiar vs. unfamiliar faces (fMRI) • Personallyfamiliarfaces • Faces: areas in the bilateral fusiform, FFA • Familiarity, regardless of modality (face or voice): paracingulategyrus including the retrosplineal cortex  suggest this region as a multimodal ‘familiarity-checking’ processor • semantic and emotional networks (autistic vs. non-autistic participants): posterior cingulate, medial frontal lobe and amygdala • personal knowledge and traits (famous vs. personally familiar faces): anterior paracingulate cortex, posterior cingulate gyrus, and the precuneus • unfamiliar faces: right amygdala and left fusiform responded more to unfamiliar faces  increased vigilance

12. 2.2 Neural systems for processing familiar vs. unfamiliar faces (fMRI) • Visuallyfamiliarfaces • new learned faces: greater activation of left medial frontal, left inferior parietal, and left precuneus • larger neural activation in the right amygdala and right middle occipital gyrus for unfamiliar faces relative to visually familiar faces  decreased (but not in right middle occipital gyrus)  responds differentially as a function of the amount of visual familiarity with faces • repeated presentation of unfamiliar faces: response in the bilateral posterior cingulate cortex increased whereas the amygdala and left medial FG response decreased • relative to the highly repeated faces, learned faces showed stronger activation of the precuneus (posterior cingulate) and less activity in the FG and intra-parietal sulcus

13. 2.2 Neural systems for processing familiar vs. unfamiliar faces (fMRI) Gobbini & Haxby (2007)