You walk briskly down a dim-lit street, dodging the daunting shadows cast by flickering street lamps. The chilly wind howls in the distance, aimlessly scattering the autumn leaves in its anger and might. Suddenly, a blood-curdling scream cuts through the silent night, propelling you to break into a run. You hear steady footsteps approaching behind you, mercilessly crushing the fallen leaves. Before you know it, an icy hand grabs your wrist. You desperately pull away your arm to break free, only to lose balance and fall helplessly on the around. As you look up in terror, a figure with razor-sharp teeth and disheveled hair looms over you. Blood trickles down its chin as it asks, “trick or treat?”
Halloween, the ultimate night of horror. With free candy, scary movies, an opportunity to show off your costumes and an excuse to party, who doesn’t love this celebration? As we lose ourselves in the spirit of Halloween, we may not realize that many associated neurological and psychological events are silently taking place. Let’s explore some aspects of this mystical realm of physiology through the experience of eight year old Jimmy.
Group Identity: Joy of Combined Superpowers and Terror of Villains
Jimmy is dressed as Cyclopse, and is ready to take on the world with the rest of his fantastical X-Men team. As the team giggles down the neighbourhood street, the brain’s superpowers are already acting in full force. Oxytocin, “a love hormone”, is produced during the pleasurable group interactions (1). It acts on a brain region called raphe nucleus to release serotonin in the nucleus accumbens, the centre of the reward circuit. Serotonin is a neurotransmitter that binds to receptors in the nucleus accumbens, providing feelings of joy and serenity. Hence, social bonding equips Jimmy and his team with the secret powers of oxytocin and serotonin.
However, where there are heroes, there are also villains. As the X-Men team marches down the street, their way is blocked by the Brotherhood of Mutants. Dressed in their menacing costumes, their evil plan is to steal candy. Why are these older children not afraid of being caught, or guilty of their intentions? According to the research from a renowned psychologist named Zimbardo, being in a group and dressing in costumes increases the chances of committing such wrongful acts (2). According to the proposed theory of deindividuation, wearing of costumes gives individuals the anonymity and alternative identity that enables them to carry out the evil deeds. The presence of other members of the team provides further arousal and a group identity, so that the person involved does not personally assume responsibility of the crime. It is through the external validation and separation from guilt that each villain can commit the heinous crime of stealing candy.
Power of Perception: Spooky Music and Dreadful Darkness
Jimmy and the remaining superheroes approach a dim-lit house, with screams and creepy music blasting through the front door. As the X-men hesitate for a moment before approaching the entrance, complex auditory and perceptual processing is underway. The amygdala, the brain’s emotional processing centre, quickly evaluates the incoming visual and auditory stimuli as spooky and initiates a generic fear response (3). The hippocampus, the brain’s memory centre, then ties the emotional input with spatial and episodic information. The prefrontal cortex, responsible for reasoning, further evaluates content and emotional tone to allow for a logical response. By linking the abstract music, visual cues and their past memories, such as prior Halloween experiences, the superheroes form an informed perception that it is safe to acquire more goods. Furthermore, the dim light increase dopamine in the frontal cortex, which controls self-regulation, so that the X-men are more cautious of potential monsters and thieves surrounding them (4). The dopamine release in the prefrontal cortex also aids with working memory, so that the team is able to recall the house that gives best candy and mark it as their next destination (5).
Magic of Altruistic Genes: Generous vs. Thrifty Candy-Givers
As the superheroes knock on the door of the dim-lit house, they are pleasantly surprised that their courage is rewarded by bags brimming with candy. As the X-men return home happily after another successful Halloween adventure, they can’t help but wonder why some home-owners gave handfuls of chocolate while others could barely spare a gummy bear pack. Although many social, psychological and physiological factors play a role in charitable acts, COMT Val158Met is a gene that may also regulate pro-social behaviour (6). The gene modulates functioning of stratum, a brain region involved in reward-related learning and containing receptors for dopamine and oxytocin. Together, dopamine and oxytocin enhances the value of social encounters. Carriers of at least one Val allele of the gene are more charitable than those homozygous for the Met allele. Since Met allele has been shown to be linked with negative emotionality, carriers of this allele are less likely to be charitable because of being overly occupied with their own problems.
Through Jimmy’s experience of Halloween, we are able to comprehend some of the neural and psychological superpowers that are concerned with the celebration. Perhaps what’s really spooky is the complexity and mystery of the physiological phenomena regulating our every move.
Written by Sana Gill
1) Gül Dölen, Ayeh Darvishzadeh, Kee Wui Huang, Robert C. Malenka. Social reward requires coordinated activity of nucleus accumbens oxytocin and serotonin. Nature. 2013 September
2) Westford, K. L., Diener, E., & Diener, C. Deindividuating effects of group presence and arousal on stealing by halloween trick-or-treaters. Proceedings of the Annual Convention of the American Psychological Association. 1973.
3) Cohen, A.J. Music as a source of emotion in film. New York: Oxford University Press. 2001.
4) O’Brien, J.Increasing Dopamine in Frontal Cortex Decreases Impulsive Tendency, UCSF-Gallo Scientists Find. July 2012.
5) Phillips, A.G., Ahn, S., Florence, S.B. Magnitude of Dopamine Release in Medial Prefrontal Cortex Predicts Accuracy of Memory on a Delayed Response Task. Journal of Neuroscience. January 2004.
6) Ebstein, R.P., Israel S., Chew S.H., Zhong, S., Knafo, A. Genetics of Human Social Behavior. Neuron. March 2010.