[tt] Brain Scans Of People Full Of Hate Show Uniqe Hate Signature

[Eugen Leitl]

(from the oh-shit dept)

http://www.futurepundit.com/archives/005665.html

October 29, 2008

Brain Scans Of People Full Of Hate Show Uniqe Hate Signature

Coming from Professor Semir Zeki and John Romaya of the Wellcome Laboratory
of Neurobiology at the University College London, a new research paper in
Plos One on how hatred activates and deactivates areas of the brain shows
hate creates a unique pattern of brain activates which includes some overlap
with brain areas activated by love.

    In this work, we address an important but unexplored topic, namely the
neural correlates of hate. In a block-design fMRI study, we scanned 17 normal
human subjects while they viewed the face of a person they hated and also
faces of acquaintances for whom they had neutral feelings. A hate score was
obtained for the object of hate for each subject and this was used as a
covariate in a between-subject random effects analysis. Viewing a hated face
resulted in increased activity in the medial frontal gyrus, right putamen,
bilaterally in premotor cortex, in the frontal pole and bilaterally in the
medial insula. We also found three areas where activation correlated linearly
with the declared level of hatred, the right insula, right premotor cortex
and the right fronto-medial gyrus. One area of deactivation was found in the
right superior frontal gyrus. The study thus shows that there is a unique
pattern of activity in the brain in the context of hate. Though distinct from
the pattern of activity that correlates with romantic love, this pattern
nevertheless shares two areas with the latter, namely the putamen and the
insula.

Hatred does not activate the amygdala which is activated by fear.

    It is important to note that the pattern revealed is distinct from that
of other, closely related, emotions such as fear, anger, aggression and
danger, even though it shares common areas with these other sentiments. Thus,
the amygdala which is strongly activated by fear (Noesselt et al. 2005 [9],
Morris et al. 2002 [10], Hadjikhani et al. 2008 [11]) and by aggression
(Beaver et al., 2008 [12]) was not activated in our study. Nor were the
anterior cingulate, hippocampus, medial temporal regions, and orbitofrontal
cortex, apparently conspicuous in anger and threat (Denson et al. 2008 [13];
Bufkin and Luttrell 2007 [14]; McClure et al. 2004 [15]), evident in our
study. It would thus seem that, though these sentiments may constitute part
of the behaviour that results from hatred, the neural pathways for hate are
distinct.

Parts of the brain involved in motor function get activated - perhaps so one
can move in and attack the object of one's hate?

    The 'hate circuit' includes structures in the cortex and in the
sub-cortex and has components that are important in generating aggressive
behaviour, and translating this into action through motor planning, as if the
brain becomes mobilised to take some action. It also involves a part of the
frontal cortex that has been considered critical in predicting the actions of
others, probably an important feature when one is confronted by a hated
person.

    The subcortical activity involves two distinct structures, the putamen
and insula. The former, which has been implicated in the perception of
contempt and disgust, may also be part of the motor system that is mobilised
to take action, since it is known to contain nerve cells that are active in
phases preparatory to making a move.

    Professor Zeki added: "Significantly, the putamen and insula are also
both activated by romantic love. This is not surprising. The putamen could
also be involved in the preparation of aggressive acts in a romantic context,
as in situations when a rival presents a danger. Previous studies have
suggested that the insula may be involved in responses to distressing
stimuli, and the viewing of both a loved and a hated face may constitute such
a distressing signal. 

While love shuts down areas of the brain associated with judgment and
reasoning by contrast those consumed with hate have very active reasoning
facilities. It takes logic to figure out how to attack your enemy. So that
makes sense. Only those in love thing they can afford to let their guard
down, become zombies, and feel bliss around the object of their affection.

    "A marked difference in the cortical pattern produced by these two
sentiments of love and hate is that, whereas with love large parts of the
cerebral cortex associated with judgment and reasoning become de-activated,
with hate only a small zone, located in the frontal cortex, becomes
de-activated. This may seem surprising since hate can also be an
all-consuming passion, just like love. But whereas in romantic love, the
lover is often less critical and judgmental regarding the loved person, it is
more likely that in the context of hate the hater may want to exercise
judgment in calculating moves to harm, injure or otherwise extract revenge.

In countries where suspected criminals have no right to privacy or right to
keep silent brain scans could be used to determine whether a suspected killer
hated his victim and by how much.

    "Interestingly, the activity in some of these structures in response to
viewing a hated face is proportional in strength to the declared intensity of
hate, thus allowing the subjective state of hate to be objectively
quantified. This finding may have legal implications in criminal cases, for
example."

One could imagine a police state in which opponents of the regime get tested
with brain scans and pictures of dictators to identify enemies of the state.
With more time it will become possible for governments to turn hatred into
love. Then all enemies of the state will get turned into supporters of it. Of
course, individuals will try to do this on a smaller scale as well.

Contrast these results with the research into love. See my previous posts
Love Deactivates Brain Areas For Fear, Planning, Critical Social Assessment,
Love Like Addiction In Brain Scans, What Brain Scans Of People Falling In
Love Tell Us, Romantic Love Seen As Motivation Or Drive Rather Than Emotional
State, and Love Is Blind: Couples In Love Can't Identify Who Else Is In Love.

By Randall Parker at 2008 October 29 12:09 AM  Brain Emotions | TrackBack