Police operations are still underway at Martin Place, with heavily armed tactical officers monitoring the Lindt cafe and chocolate store where hostages are held captive.
While five hostages have escaped, there could be as many as a dozen still left inside with the armed offender.
On Sky News, Professor Jayashri Kulkarni, director of the Monash Alfred Psychiatry research centre in Melbourne discussed the psychological impact of being held hostage and the symptoms they would be feeling 13 hours into the siege.
She said the initial anxiety would be starting to wear off and a life-threatening situation is “the most severe thing a human being can face”.
“The physical reactions in the very first instance are the heart racing fact, blood pressure going up, nausea, vomiting, jelly legs – all the symptoms of severe anxiety – and some people have panic attacks,” she said.
“That’s all happening in the early stages but then most people, as the initial severe shock is starting diminish, that’s when people go into their own coping mechanisms to deal with what else is going on.”
While Kulkarni said each individual reacts differently according to their personality, experience and lifestyle, it also depends on who they are with.
“A parent with a child, or person with a friend, or frail or elderly person with them, is more likely to cope by focusing on that individual – that is going to be the centre of their attention,” she said.
“Others might cope by having a self meditative view of things so they become mute almost. Other people want to talk and they might try and engage the perpetrator and conversations with others.. but there are many different coping styles.
“We don’t know the conditions that the people are in inside this particular hostage situation, and we don’t know the individuals… usually in my experience self-preservation is the upper most impulse.”
Looking into what the hostages, and those who have escaped, could experience in the next couple of hours and longer, Kulkarni said post-traumatic stress is likely to set in.
“Mostly in the next short space of time there will be post-traumatic stress,” she said. “There will be experiences of re-living the whole trauma, again having a sense of unreality.”
Darkness also influences the situation.
“We are now in the 13th hour… and it’s also night time and of course generally things become more out of control and feel worse when it’s dark outside,” she said, adding that humans are remarkably resilient.
“In the face of adversity people do actually find strength and resources within themselves that they didn’t realise they had. But everyone will require good physiological help even to de-brief the person who has been through the situation and move on from there.”
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