Facial recognition ability
Is there a theoretical reason why the right hemisphere differs from the left hemisphere in facial recognition ability? What empirical evidence supports/refutes this alleged difference?
Variance in Facial Recognition between the Right Hemisphere and the Left Hemisphere
The brain’s ability to conduct facial recognition is regarded as a qualitatively distinctive pattern from other patterns of recognition. Facial recognition can in this regard be described as a process of identification and subsequent verification of an individuals’ identity through the mental analysis of their facial features. Inquiries been made regarding the variant abilities of the different brain hemispheres in the process of facial recognition. It should be noted in this respect that the brain is made up of two major hemispheres: the right and left hemisphere (the left hemisphere generally controls the right side of the body and it is responsible for performance of ‘logic-related’ tasks such as mathematics and science; while the right hemisphere controls the left side of the body and is responsible for tasks that are related to creativity and arts). A common claim that has been seen to arise in relation to facial recognition is that the right hemisphere has an ascertained degree of dominance when it comes to recognition of upright faces while the left hemisphere has some unique advantages in this regard particularly when there is support from the right hemisphere. It has essentially become apparent that processing of facial features require bilateral involvement. This paper will provide an in-depth inquiry into whether there is a theoretical reason as to why the right hemisphere differs from the left hemisphere in facial recognition ability. The argument presented in this paper is that the two brain regions play distinctive yet complimentary roles in facial recognition ability and in this regard, theoretical reasons behind this phenomenon will be provided through the use of literature review.
One of the fundamental theories behind the variance in facial recognition between the right and left hemisphere is the unique processing abilities that are wielded by the two hemispheres. Generally, the right hemisphere specializes in holistic processing while the left hemisphere focuses on analytical processing (Bruyer, 2014, p. 125). Due to the right hemisphere’s ability to conduct holistic processing, it has a unique advantage when it comes to facial recognition since it focuses on “configuration attributes such as contour of the face or the spatial relationships among features” (Bruyer, 2014, p. 125). On the other hand, as noted above, the left hemisphere conducts analytical processing and this attribute gives it an advantage when it comes to facial recognition because it places more focus on certain distinctive features of the face such as the eyes and nose. Essentially, due to the variance in the processing abilities of the right and left hemisphere, there is a concomitant variance with respect to the manner in which both sides of the brain conduct facial recognition. The variance in processing ability is, therefore, one of the fundamental reasons behind the differential facial recognition ability. This shows that although the facial recognition activities conducted by both sides of the brain are variant, facial recognition required bilateral involvement.
The variance in face processing mechanisms between the right hemisphere and the left hemisphere also arises from the lateralization of face processing between the two different regions. Meng et al. (2012) conducted a study to analyze the lateral differences in racial recognition between the two regions. Particular focus was placed on the left and right fusiform gyri. The results of the study revealed that “neural activity patterns in the right fusiform gyrus change in a manner consistent with behavioral face/non-face categorical judgments” (Meng, 2012, p. 2058). On the other hand, the “brain activation pattern in the left fusiform gyrus appears to correspond to image-level face similarity” (Meng, 2012, p. 2058). The participants of the above-stated study were required to select face-like features in different images and photos that they were given and it became apparent that the two brain hemispheres played different roles in the detection of the face-like features. The hemispheric difference was particularly seen in the univariate amplitude examination (Meng et al., 2012). Based on the foregoing, it is apparent that the different laterization in face processing in relation to the right and left hemisphere play a significant role in the variance in facial recognition ability. Despite this variance, both regions are useful in facial recognition.
Another theoretical factor that leads to a fundamental variance in facial recognition between the left and right hemisphere is the fact that face selectivity often persists in the right hemisphere even after activities have been returned to baseline (Volberg, 2014). Based on the above study as conducted by Meng et al. (2012), it was apparent that “the categorical responses in the right fusiform persist at least until 8 seconds after the stimulus onset even though the stimuli are much shorter in duration” (Meng et al., 2012, p. 2060). It was further noted that after 8 seconds of withdrawal of the stimulus, activities in the left fusiform return to baseline. Even though both sides of the brain were seen to play critical roles in facial recognition, the right hemisphere recorded a longer recording of the facial image and a lengthier period of face selectivity. In this regard, the right hemisphere can be said to be responsible for the storage of information on facial features for a longer period of time. To this extent, there is a clear variance in facial recognition abilities between the left and the right hemispheres. The two regions, however, support each other in facial recognition.
Another significant theoretical variance in facial recognition between the left and right hemisphere can be illustrated by reference to the extent to which both regions are able to recognize facial expressions. In a study that was conducted by Hugdahl et al. (1988), twenty-eight subjects were presented with nine drawings that contained different facial expressions. The researchers conducted this activity with the intent of noting the extent to which the participants would be able to recognize the correct face the use of the right hemisphere vis-à-vis the left hemisphere. The results generally showed a better level of recognition in the right hemisphere as compared to the left hemisphere (Hugdahl, 1988). The extent to which the two hemispheres respond differently to emotional expressions on the face thereby culminating in a variance in facial recognition is evidence of the fact that the two regions play different roles in facial recognition. In this regard, even though facial recognition is a binary activity, the different regions of the brain play different roles.
The variance in facial recognition between the two hemispheres also comes about due to the variation in hemispheric specialization between the two regions. Based on a study that was conducted by Volberg (2014), this variance was acknowledged. The researcher particularly recognized the fact that the right hemisphere exhibited “dominance in global processing” as compared to the left hemisphere (Volberg, 2014, p. 7). The researcher also delved into an analysis of the factors that caused this dominance. It is important to note that as alluded to above, in line with the identification of global visual patterns, the right hemisphere is responsible for the analysis of the contours of the face, as well as, the “distance relationship among facial features” (Koob, Le Moal & Thompson, 2010, p. 24). The left hemisphere, on the other hand, is responsible for analyzing the “local aspects of visual stimuli” such as the “individual features of the face” (Koob, Le Moal & Thompson, 2010, p. 24). Both sides of the brain, therefore, play variant but critical roles in facial recognition. It is particularly important to note in this regard that both studies involving normal individuals and those involving individuals who brain impairments show that facial recognition requires a binary involvement. As explained by Bruyer (2014), numerous studies have in fact shown that “under certain conditions, the processing of faces may be superior in the left than the right hemisphere” and vice versa (Bruyer, 2014, p. 125). Facial recognition is as such a binary activity.
Conclusively, the ability of the brain to conduct facial recognition is regarded as a qualitatively distinct pattern. One of the theories that have often been fronted in relation to facial recognition is that the right hemisphere plays a predominant role in facial expression. This is, however, inaccurate since both regions play distinctive roles with regard to facial recognition. The first theoretical reason behind this phenomenon is that the two hemispheres generally have different processing abilities. The second theoretical reason is the variance in lateralization of face processing between the two hemispheres. Face selectivity is also different between the two hemispheres and the manner in which the two regions react to facial expressions is also variant. The variations that exist between the left and the right hemispheres can also be reflected in the manner in which the two regions conduct facial recognition. What is learned from the reading of this paper is that facial recognition is a binary activity and both regions of the brain play distinctive roles in this regard.
Bruyer, R. (Ed.). (2014). The neuropsychology of face perception and facial expression. Psychology Press.
Hugdahl, K., Iversen, P. M., Ness, H. M., & Flaten, M. A. (1989). Hemispheric differences in recognition of facial expressions: a VHF-study of negative, positive, and neutral emotions. International Journal of Neuroscience, 45(3-4), 205-213.
Koob, G. F., Le Moal, M., & Thompson, R. F. (2010). Encyclopedia of behavioral neuroscience. Elsevier.
Meng, M., Cherian, T., Singal, G., & Sinha, P. (2012). Lateralization of face processing in the human brain. Proceedings of the Royal Society B: Biological Sciences, 279(1735), 2052-2061.
Volberg, G. (2014). Right-hemisphere specialization for contour grouping. Experimental psychology.