The medial prefrontal cortex, or mPFC, is a part of the human brain that records human activities, and is a good tool to make predictions about to what extent people can be persuaded. (Representational Image)
Neuromarketing, or the assessment of physiological and neural signals of an individual to gain insight into customers’ motivations, preferences, and decision making, is a phenomenon neuroscientists have been investigating for decades now, to see whether it can be utilized to predict future occurrences. fNIRS (Functional Near Infrared Spectroscopy) is an emerging neuroimaging technology, used to measure brain activity, and is arguably a game-changer in the field.
Studies have been done, and are still going on to understand the scope of predicting future behaviour through this technology, such as ‘fNIRS Replication of the Sunscreen Persuasion Paradigm’ by Shannon Burns. According to the studies, the images produced by fNIRS can help predict a person’s future behaviour based on a few factors. Prof Murat Cakir, a cognitive science professor in the Middle East, in his study, titled 'An investigation of the neural correlates of purchase behaviour through fNIRS', argues that fNIRS can provide biomarkers to improve purchasing tendencies’ classification accuracy since it is less expensive than fMRI (Functional Magnetic Resonance Imaging), which also measures brain activity.
Paola Pinti, in her study ‘The present and future use of fNIRS for cognitive neuroscience’, claims that the technology can monitor cortical hemodynamics during movement or walking tasks, which scanners in a restrained environment can’t do.
To understand how fNIRS can measure future behaviour, the art of persuasion was taken as a case study. A successful persuasion requires one to make a change in an individual’s otherwise uninterrupted behaviour pattern. The medial prefrontal cortex, or mPFC, is a part of the human brain that records human activities, and is a good tool to make predictions about to what extent people can be persuaded. This brain activity image is a better predictor of future behaviour than a person’s self-report, which has its own biases.
The "brain-as-predictor" approach has been used by researchers to predict how people will respond to a persuasive message. Numerous studies have identified mPFC as the central predictor, and what makes fNIRS better than fMRI is that it can test real-world persuasion as it happens. Patients need not get into a scanner.
How does this work? Concentrations of oxygenated and deoxygenated hemoglobin (HbO and HbR) from the cortex are used to indirectly measure brain activity. fNIRS rely on optical properties, light emitters and detectors placed on the scalp for this process. Participants can wear headbands or caps and hold the optodes on their heads. On the replication of the ‘sunscreen persuasion’ paradigm, Burns’ team noted that greater mPFC activity during persuasion positively predicted future use of the sunscreen better than the participants’ self-reports.
The results for users and non-users of sunscreen were different. The non-users’ brain activity predicted user behaviour much better than those who already use sunscreen.
In addition, the group observed that the dorsolateral prefrontal cortex or dIPFC activity is negatively associated with the future use of sunscreen. If paired with mPFC, the future behaviour prediction could be better. This was examined during past studies that mentioned dIPFC to be associated with resistance and counterarguing. It can pose the question, "if there is an x amount of persuasion and a y amount of resistance, will it lead to a belief and behaviour change?"
The study also found no significant difference in the results from persuasive messages – whether persuasion was posed as "gain" or "loss." This means if you pose a product as "you gain better health" or "you’ll lose stubborn fat," the structure of the persuasive message does not lead to much different result.
Cakir’s team also noted that neural activity through the frontopolar regions as measured by fNIRS significantly increased when people make positive purchasing decisions. According to the study, neural activation can help decode a person’s buy or pass judgment with 85% accuracy, with the budget constraint as a factor.
All these studies validate the argument that given its accessibility and advantages over fMRI and other similar technologies, it can be of immense use for marketing teams and community researchers.
fNIRS is also helpful in examining psychiatric conditions. Professionals are of the opinion that, unlike other technologies, fNIRS is considered more portable, accessible, tolerable, safe, and affordable to use. A patient undergoing the test doesn’t need to stay away from their daily routine to go to a laboratory. The test can be done without any hindrance to any individual’s daily routine.
This article has been written by Akshat Jain, Research Scholar, Indian Institute of Technology Delhi. Scholar is a graduate from BITS Pilani and pursuing his research studies in the field of Psychology and Neuroscience.