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The Extrastriate Body Area (EBA) is a part of the human extrastriate visual cortex, which in turn is a subpart of the visual cortex. It is one of the two main brain areas involved in the visual perception and representation of human bodies, alongside the Fusiform Body Area (FBA). The EBA was first identified in 2001 using Functional Magnetic Resonance Imaging (fMRI).

Location
The EBA is located in the lateral occipitotemporal cortex, which is a part of the occipital and temporal lobes. This area resides within brodmann area 19.

Typically, activation within the right hemisphere is greater, which suggests possible brain lateralization.

Localization
The EBA was first localized by Paul Downing and colleagues working in Nancy Kanwisher's lab with an fMRI experiment. The researchers showed participants images of bodies and images of various inanimate objects, When brain activation from the fMRI scan was compared, activation in one region of the brain was much stronger for bodies compared to objects. The researchers termed this brain area the Extrastriate Body Area (EBA). Neuroimaging evidence for the existence of EBA has been well-replicated, however it is not enough to conclude that the EBA is a centre for body perception in the brain.

Transcranial magnetic stimulation (TMS) is a neurostimulation research method used for testing whether a brain area has a causal function for a given cognitive domain, in this case body perception. Indeed, TMS studies show that temporarily disrupting activity in the EBA affects how participants perceive and respond to bodies. For example, applying TMS stimulation and disrupting activity over the EBA, but not other regions such as the OFA, has been associated with slower and less accurate responses on body categorization tasks. The results from both neuroimaging and neurostimulation research show that the EBA has a strong implication in body perception and representation.

Function
The EBA is thought to be involved in various cognitive functions. The main research finding is it is heavily involved in body perception. More specifically, the EBA has the strongest neural activity when participants are presented with whole bodies, or separate body parts. This area is different to face brain areas such as the FFA, as neural activity in the EBA decreases when there is a face present compared to when there is no face present on a body.

Identity Perception
Some researchers have suggested that the EBA might play a role in body identity perception. Research has shown that brain activity in the EBA is greater for own body parts compared to other people's bodies and disrupting activity in the EBA has a negative impact on task performance. For example, one study utilising TMS found that participants made more errors in recognizing other people's hands when TMS was applied over the right EBA, and more errors categorizing their own hands when TMS was applied on the left EBA. The authors argued that the EBA has an effect on identity perception that is lateralized differently between the left and the right EBA. However, these findings are heavily debated, as many other authors investigating this effect have not found significant results.

Because of these contrasting research findings, the main literature consensus is that the EBA is not directly involved in person identity perception, but rather it is a part of the visual system that passes on information to later brain areas which are more heavily involved in identity perception.

Motor implications
Researchers have found that the EBA responds more to bodies, regardless of whether they are moving or not. Therefore, motor movements and actions do not lead to a higher brain activity in the EBA compared to static bodies and body parts. However, brain activity in the EBA while participants are performing unseen motor tasks (e.g. moving fingers or toes) is comparable to while they are viewing body parts. Therefore, researchers looked at the involvement and the functional connectivity between the EBA and other motor areas and found that the EBA is involved in behaviours related to motion, such as preparing to perform actions and discriminating between actions. For example, the EBA shows a different multivoxel pattern analysis results, discriminating between initiating and responding to actions of another person.

Emotion
The EBA has been implicated as an area affecting emotion perception. Specifically, neural activation in the EBA is increased for bodies portraying an emotional pose (e.g. fearful or joyful) compared to bodies in a neutral pose. The EBA has been found to be active at the same time as, and connected to, the amygdala, which is the main emotional processing area in the brain. This activation is found for children, adolescents and adults alike. However, for these effects to be significant, bodies need to be very clear in portraying the specific emotion, more so than real-life casual human interactions. Furthermore, the response in the EBA can be elicited from body parts (e.g. torso with hands) without presenting whole bodies. Therefore, it has been theorized that the EBA responds to very strong emotions, which are difficult to interpret from faces alone and require additional context information, i.e. the rest of the body.

Disorders
Abnormalities in the EBA have been connected to several clinical disorders.

Anorexia Nervosa
The EBA has been associated with the Anorexia Nervosa (AN) eating disorder. Specifically, people with AN have physical differences in reduced density of the grey matter in both EBA regions, as well as a reduced connectivity pathways between the left FBA and EBA. These differences are thought to contribute towards viewing one's own body more negatively, which is a major symptom in AN.

Schizophrenia
People with schizophrenia have a reduced neural activation of the EBA compared to typically developing people. This effect has been connected to impairments in stimulation, learning, and execution of actions. Reduced functional connectivity between the EBA and sensorimotor areas has been implicated as a potential cause behind these effects. Physical exercise has been found to influence brain activity in patients with schizophrenia, however the exact effects on the EBA and the associated symptoms are not yet known.