When the animal instinct takes over

Huge quantities of drugs such as cannabis and cocaine are feeding the rapid spread of violent behaviour, warns consultant Chris Luke

PROBABLY the most

striking comment in recent coverage of the ever-worsening problem of

Somali piracy was that by a BBC World Service expert who observed the

pirates "had no fear of dying" whatsoever.

The expert also reminded listeners that a ragged band of the pirates'

countrymen had succeeded in chasing America's elite soldiers from

Mogadishu in 1993 (an ignominious piece of recent "peace-keeping"

history that was memorably depicted in the film, Black Hawk Down).

And to emphasise the ferocity of the Somalis, on the same day the most

significant item in the printed media's coverage of the piratical

contagion was a report that an Indian warship had been attacked by a pirate

"mothership" which was then

(predictably) blown out of the water.

Such indifference by those

responsible to the risks to life or limb would seem to be a mysterious

but fantastic aptitude in any army, but it is not quite as inexplicable

as it might at first seem.

The diagnosis is simple enough:

easily available weaponry and drugs.

In the case of the exceptionally

violent, wealthy and gun-toting young brigands of the Horn of Africa,

the intoxicating culprit is khat - the

local trance-inducing leaf that is a

staple of daily life in that part of the world, and which might be

thought of as a kind of African coca leaf.

Remarkably, for those of us who have to contend with really serious

violence in Ireland, the worsening

anarchy around the Western reaches of the Indian Ocean is actually

frighteningly comparable with the drug-induced violence that is

spreading virally around this little


And the reason for being so fearful is that most of the violence

reported almost daily is now clearly "limbic" - a descriptive medical

word which sadly resonates with cities like

Limerick and Dublin in more ways than one.

The "limbic system" is a

neighbourhood of brain structures (with intriguing 19th century names,

like hippocampus, amygdala and

nucleus accumbens), which are

crucially concerned with regulating "higher" human functions like

emotion, behaviour, long-term

memory, and smell.

As with all brain science, a precise understanding of the system is

decades away, but what seems to be emerging is of profound importance to the

contemporary debate about violence in the human world, and most

importantly in contemporary Ireland.

Put crudely, the limbic system is a crucial "relay station" between

higher brain centres and the hind brain and spinal cord: in a nutshell,

it connects the primitive impulsive nervous

system with the evolved self-reflective human "mind".

And it is increasingly thought to be pivotal in the way emotional

behaviours are self-regulated.

Originally, the basis of this discovery was postmortem studies of the

brains of emotionally-disturbed individuals, but recent scientific

research has placed the system at the root of a great deal of bizarre,

aggressive and highly excitable behaviour.

Unsurprising too is the particularly intimate place in all of this of the

nucleus accumbens, the brain's so-called "pleasure centre", which plays

a role in sexual arousal and the "high" derived from recreational drugs.

The growing body of research

findings regarding the limbic system is fascinating in itself, of

course, but the practical implications should be of

immense interest to policy-makers, politicians and people in general. Why?

Well because science now explains what advertising executives have

understood for so long: men really can't help acting on impulse.

And messing with the limbic system means that men (and women) will be

driven - uninhibited by normal "thoughtfulness" - by the most primitive


The results can be devastating, as Dr Harry Barry, an inspiring Louth

general practitioner, recently argued at a conference in Cork on

depression and suicide.

He cogently explained that many of our young male suicides (especially)

had absolutely no prior intention of taking their lives but the

compromise of their limbic systems, induced by any assortment of

intoxicating agents, from alcohol to cannabis, magic mushrooms or

cocaine, meant that they acted lethally purely out of

primordial instinct or impulse. In

other words, no thinking was


Of course, precisely the same

impulsivity applies in many homicides.

Indeed, the more unprovoked,

brutal, or inexplicable the killing is, the more likely that limbic

system malfunction has caused the literally "sub-human" behaviour.

Such malfunction can occur after head injury, severe infections or

malnutrition and it can occur

congenitally (as in foetal alcohol

syndrome or in association with

maternal smoking), creating "terrible toddlers".

However, the vast majority of cases of consequence are due to

intoxication in young adults. And the more drugs - particularly alcohol,

cannabis and cocaine - that are

consumed, the more likely that limbic system malfunction will occur,

with catastrophic consequences.

Taking these drugs together can produce a terrifying synergy, which may

kill the user suddenly or lead them to kill others, abruptly.

None of this comes as any great

surprise to historians of warfare who have long understood that the

"destructive instinct that impels men to war... is a weak one, and often

requires a great deal of help".

So Alexander the Great's Greek

hoplites drank copious amounts of wine before battle, as did Chinese

troops in the era of Sun Tzu; Aztecs drank pulque (a beer made from the

cactus-like maguey plant), Yanomamo Indians of the Amazon ingested an

hallucinogenic concoction and the Ancient Scythians smoked marijuana.

The net, predictable result was a kind of "limbic trance" which enabled

the unthinking warrior to "mimic the devouring wild dog".

Perhaps the best cinematic example of the awesome power of "limbic

trance" is seen in the movie Zulu, which depicted the Battle of

Isandlwana in 1879, when 20,000

Zulu Impi warriors sprinted through a hail of bullets to ritually

disembowel 1,300 well-armed British soldiers.

Historians believe that this stunning victory

was enabled by a fear-aborting cocktail fed to the Impi, of high-potency

cannabis snuff, pain-killing "Bushman Poison Bulb" and

hallucinogenic red mushrooms.

Two centuries later and a

hemisphere away, similar limbic system behavioural predominance is

occurring all over this island.

The usual suspects (maternal, paternal, fraternal) are at work but

critical new elements are industrial quantities of cannabis, cocaine and


The recent appalling murders of Shane Geoghegan and Roy Collins -

classics of the impulsive, indiscriminate, "limbic" sort - led some to

describe the perpetrators as "scum".

Such language is understandable, but ironically it is itself impulsive, and

distracts us from the core issue.

"Scum" is an unhelpful word

because violence is not about the "worth" of a person, moral or

otherwise, but is primarily about

uncontrolled impulses.

And the prevention of violence must focus on restoring the natural and

necessary regulation of impulsivity by the normally working mind.

This of course means impulsivity uncontrolled by both on-off and

perpetual intoxication (which means that the violence becomes part of

the drug-using community's standard behavioural "norm", even at times

when a drug hasn't just been consumed).

As a society, we can take comfort

in the knowledge that few humans are innately homicidal. But we must

learn from history: from Vietnam to

Isandlwana, from the Congo to Croom, homicide, massacre and

genocide are rarely committed by the completely sober.

They are fuelled - often at the

behest of cunning commanders - by a toxic impulsivity that lurks beneath

the higher brain structures in all of us.

Understanding this offers prospects for progress through calibrated

treatment of identifiable deficiencies, whether they be nutritional,

educational or, above all, toxicological.

But to any lawyer or libertarian who might seek to explain away this

predictable, self-inflicted malfunction, I would advise against formally

blaming the limbic system just yet.

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