N170 Object Recognition

In the neuropsychological field, one way to know whether the processing of face is carried out by the domain-specificity or domain-general mechanism is to study patients with brain damage in visual areas. For example, patients CK who lost ability to recognize objects after a car accident performed perfectly on the tasks of face recognition. () Meanwhile, many cases of patients who suffered prosopagnosia, their ability of object identification remains intact. It suggests there is a double dissociation between face and object recognition.
Although it helps us to know face and object recognition may not activate the same region of the brain areas, we do not know yet which areas are responsible to them respectively if they are really two distinct
Emier () who published an article about summarizing the contributions of N170 to face perception mentioned that this face-sensitive event-related brain potential (ERP) has no correlation with the familiarity of faces. It also suggested that the N170 has already appeared before the subjects recognized the faces. Hence, it could be considered as a component to encode the perceptual structure of stimulus from the very beginning stage of identification. Other than finding the responded region for face, more importantly, I think it could find out more other functions of fusiform face area (FFA). In this case, we can know that FFA is also responsible to detect faces. In my opinion, the future study could try to focus on whether there is any significant difference of identification between ethnicities or age
Through observing the region of interest (ROI) of face, Kanwisher () noticed there is a six-fold increase in subjects’ response during viewing faces compared to viewing houses. In terms of the results, I wonder whether the term “specialized cortical region” is still appropriate to describe the region. As my knowledge, this term is simply meaning that neurons of these regions are only activated by the face stimuli. If the experiment found out it could respond to another type of stimuli then we should not say it is specialized for face stimuli but I would rather say that it selectively responds more to face stimuli.
Besides, many researchers tried to know how the FFA responds to the face stimuli with different orientation. Several studies have demonstrated that there is a much larger impact on inverted face than upright face in terms of face recognition.() On the basis of the assumption that people are using a configural process to analyze faces, the face inversion effect would make people more difficult to encode the perceptual information. Evidence from ERPs (), the N170, which is regarded as the important component for face perception, is delayed by about 10 ms during the inversion task compared to normal face-stimuli