Psychology essay - What can neuroscience tell us about the biological basis of morality?
The Neurological Basis of Morality
Morality is a system within human social behaviour which guides our behaviour along a set of guidelines, such as; fairness, self-control and empathy. These guidelines are shaped by moral emotion such as anger towards unfairness which are the products of evolutionary pressures on social animals.
Neurological studies aim to pinpoint the areas responsible for morality and how these regions interact. Historically, one of the best ways to gain insight into brain function is to look at patients with brain damage. In this case, the most widely studied disease is frontotemporal dementia (FTD). FTD is a neurodegenerative disease affecting the prefrontal and anterior temporal cortex thus leading to significant personality changes (Neary, Snowden & Mann, 2005), particularly, a distortion of ‘morality’ by exhibition of antisocial behaviours (Mendez 2006). Mendez (2005) gathered FTD patients who displayed frontal lobe abnormalities in functional imaging scans and presented an inventory of moral knowledge and two moral dilemmas – in order to test their retention of moral knowledge and their ability to apply this to dilemmas. Greene et al. (2004) suggest there are two types of judgement mechanisms when it comes to moral dilemmas: personal and impersonal. The key difference being the involvement of emotion due to harm arising without the direct deflection of a threat. A popular example of a personal moral dilemma is the footbridge problem where in order to stop a train from killing several people tied to a track you would have to push a larger person off a footbridge. In Mendez’ study, they found that FTD patients had preserved their moral knowledge and the ability to make “impersonal” moral judgements. However, compared to Alzheimer’s Disease patients and control patients, there was an impairment in the ability to make “immediate, emotionally based moral judgements”. This evidence would suggest that FTD patients are aware of moral ‘rules’ and can apply this to impersonal situations requiring cognitive abilities only, but when socio-emotional regulation is needed, the patients are unable to judge moral dilemmas. Hence, there is an impairment in moral judgement due to the degeneration of areas within the frontal/temporal lobe.
A sub-category of FTD is a condition known as behavioural variant frontal temporal dementia (bvFTD) in which there is substantial changes in the patient’s personality and social behaviour (Neary, Snowden and Mann, 2005) greater than those seen in FTD patients. Studies into the neuropathology of bvFTD suggest that the areas most commonly involved in the observed changes in personality and behaviour are the orbitofrontal cortex and the anterior insula (Hornberger 2011). These findings would suggest that these areas play a pivotal role in the organisation and regulation of social behaviour which can lead to ‘immoral’ behaviours and an impairment of moral judgement highlighted later in this paper.
Another way of testing the neurological basis of morality is looking into ‘acquired sociopathy’. This describes cases in which a patient has acquired a brain lesion which leads to changes in personality like those seen in FTD patients. Studies into lesion patients displaying sociopathic personality tendencies have suggested that the ventromedial prefrontal cortex (VMPFC) is very important in the socio-emotional function required to make moral judgements (Tranel & Bechara, 2002).
It is suggested that this is because the VMPFC allows you to apply previously learned socio-emotional knowledge to a new situation and predict the emotional consequences of their actions (Bechara, Damasio, Damasio & Anderson, 1994). A further area deemed important in moral judgement is the previously mentioned OFC, due to studies into OFC lesions indicating an impairment in using socioemotional cues (e.g. facial expressions of anger) to judge how appropriate a response is and hence struggle to control impulsive reactions (Blair 2004). This evidence would suggest that there is a “morality network” mainly consisting of the VMPFC and OFC due to impairments in this “network” correlating with immoral behaviours and lack of moral judgement.
A group of individuals most commonly considered as being “immoral” are psychopaths. Psychopathy can be described as an antisocial personality disorder where there is a disconnect between knowing what is right and doing what is right (Moll, Oliveria-Souza & Esling, 2003). There have been many studies using brain scans of those considered psychopaths (mainly those imprisoned for violent crimes), for example, a study by Seidenwurm et al. in 1997 showed reduced temporal lobe metabolism, correlating with observed limbic abnormalities. Other studies suggest this reduced metabolism is present in the prefrontal lobes as well (Raine et al., 1994). A further study into the moral decision making in psychopaths by Glenn, Raine and Schug (2009), used fMRI data to suggest a reduction in amygdala activity during emotional moral decision making. The amygdala is thought to be essential in averting individuals from antisocial behaviour by responding to signals of stress exhibited by others (Blair, Mitchell & Blair, 2007). This evidence would suggest that those with psychopathic tendencies have abnormalities in their “morality network”, mainly due to amygdala dysfunction. Other studies have found an impairment in amygdala dysfunction in psychopaths (Blair 2005) leading to dysfunction in distress cue processing and a failure to develop moral behaviour. To back up the theory that the amygdala is important in moral decision making, animal studies have suggested that early dysfunction in the amygdala disturbs the natural development of the VMPFC and OFC (Blair 2005). Studies into psychopathy have provided more evidence to back up the idea of a morality network and enhance our understanding of the disorder but also add a layer of complexity to the understanding of morality by considering the role of emotion via the amygdala.
Neuroimaging of those without deficit in morality allows researchers to investigate areas of the brain active during these tasks. Greene, et al. (2001), inspired by the trolley and footbridge dilemma, designed a study to investigate the neurological basis for the difference between these two dilemmas.
They originally hypothesised that the emotional engagement in the footbridge dilemma was responsible for the difference in responses so predicted areas involved with emotional moral reasoning would be more active during the solving of these dilemmas. Sixty practical dilemmas were split into moral and non-moral (e.g. choosing which coupon to use). Next, moral dilemmas were categorised into moral personal and moral impersonal, examples being steeling someone’s organs to save 5 other people and keeping money found in a lost wallet respectively. Nine people judged these dilemmas under fMRI as either “appropriate” or “inappropriate”. The results indicated several brain areas were significantly more active during moral personal dilemmas than moral impersonal and non-moral dilemmas. These areas consisted of Brodmann’s area (BA) 9 (dorsolateral prefrontal cortex), 10 (anterior prefrontal cortex), 31 (dorsal posterior cingulate nucleus) and 39 (angular gyrus). Several different studies have identified these areas as having an involvement in emotion and decision making (Lane, et al. 1997, Soon, et al. 2008, Francis, et al. 2001, Seghlier 2012). This evidence would suggest that there is a line between the judgement of personal/impersonal moral dilemmas which is defined by the involvement of emotion, supporting the findings in psychopathy studies.
It has been established that there is a system for the judgement of ‘emotional’ moral dilemmas and ‘cognitive’ moral dilemmas, but how is this system regulated and how is one to decide the differences between these dilemmas when there are so many different variations? What sparks the employment of emotion into these decisions? An area suggested to play a role in ‘overlooking’ the areas responsible for this ‘line of judgement’ is the anterior cingulate cortex (ACC) which is an important region for theory of mind (ToM) (Pascual et al 2013). ToM allows you internalise the mental states of others as different from your own. Bzdok et al (2012) found an overlap between areas active during moral cognitive tasks and areas involved in ToM and empathy tasks, however, there was a higher overlap with ToM. The results from this analysis suggest that ToM plays a big role moral reasoning with empathy also playing a small part. Findings have also suggested that the temporal lobe is active during ToM tasks and impairments in this region being linked to psychopathy (Pascual et all 2013), further backing up the role it plays in morality.
Overall, neurological evidence has provided a solid base for what appears to be a network within the brain which allows one to take part in moral reasoning. Evolutionarily, this network is very important for social behaviour by installing an innate set of “rules” which allow social communities to cooperate and coexist. Studies into those which have shown an impairment in areas of the brain proposed to make up this network (e.g. VMPFC and amygdala), such as FTD patients and those with psychopathy, back up the idea of a neural system involved in the process of moral reasoning. However, these studies show that most of these individuals have preserved moral knowledge but cannot apply this knowledge to real life situations. It is clear that there are many systems responsible for morality and even more clear that these systems overlap and work together to help guide us through the social world.
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