“Why then?” I asked as he rinsed out our cups and selected another tea for himself.
“Because it was the full moon,” he said matter-of-factly. “Studies on emergency department admissions around the times of full moons seem to be both contradictory and inconclusive, but what stands out from them is that there’s a significant increase in admissions of those with personality disorders, and the triage codes for those tend to be more severe than your average psychiatric admission. One oddity there is that people with paranoid schizophrenia are more likely to be admitted at the time of the full moon than at any other period. Alright, we’re talking about little more than a ten per cent increase on the average figures, but that’s still far too high, mathematically speaking, to be purely coincidental.”
“I thought most schizophrenics with paranoia weren’t usually particularly violent.”
“Most might not be, most of the time, and certainly not if they’re on the right medication. Second-generation antipsychotics are very effective, once the correct prescription and dosage is being followed.” He shrugged. “But without medication? The delusions and hallucinations can be utterly overwhelming. You should read Karl Friston’s notes from his time at the Littlemore mental health facility in Oxford. One of his female patients decapitated her neighbour with a kitchen knife. Apparently he’d turned into an evil, human-sized cow, so, right, obviously he needed to be dealt with.”
Friston? Why did that name ring a bell? Ah, I remembered. Shay had been going on last year about the man’s Free Energy Principle being a better model for programming an AI system than reinforcement learning was. The goal, Shay said, was to minimise prediction error, not just create a system that could perform well in a stable, rule-bound environment. The man was one of those eccentric super geniuses of the kind that seemed to fascinate my cousin. Shay certainly never gave me the impression that he felt deprived of peers who could provide him with intellectual stimulation. How he’d have fared in an earlier age, without the world at his fingertips, was another matter entirely.
“I’m not surprised the pierced eyeballs were bothering you either,” Shay remarked as he put a freshly brewed double espresso down in front of me. It was probably a decaf, knowing him, but I didn’t mind; it tasted a hell of a lot better than the tea had. “It’s not quite the same thing as enucleation, which is the technical term for gouging the eyes out, but it seems significant.” He sat down again with his own fresh drink. “That’s a relatively rare form of assault documented in psychotic patients, and some psychopaths too. I can dig up a study on the subject I came across a few years back for you if you like, but it’s not pleasant reading. A lot of the cases included in it involved various other forms of physical mutilation as well, and a considerable number of them were committed during, or after, sexual assaults too.”
A faint but pleasant scent of cardamom wafted my way as he sipped in satisfaction at his favourite masala chai blend. Maybe I wasn’t the only one who hadn’t been impressed by the new tea.
“And then there were the religious delusions,” he continued. “Gouging out the eyeballs to exorcise the devil... actually quite a few of those involved patients doing it to themselves rather than to somebody else. More encouragingly, once the right medication was hit upon, most of their symptoms disappeared. The hallucinations and delusions all stopped and the formerly violent patients became quite docile and manageable again and even expressed remorse for their earlier actions. Mind you, that study’s eighteen years old now. I wonder if I can find anything more recent?”
Christ! He might as well have been discussing something as mundane as a broken washing machine, rather than mental illnesses that were the stuff of nightmares.
“So you believe our killer is probably schizophrenic, possibly also psychopathic, off their meds and totally delusional?”
“Well, not exactly,” he disagreed. “For one thing, they may not ever have been prescribed medication for their condition. We might be dealing with someone who hasn’t been diagnosed yet. And I really don’t like fixing labels on undefined mental disorders like that. Let’s just say that it’s highly likely that our culprit is suffering from a psychotic disorder, either naturally occurring, due to genetic factors or physical damage to the brain, or, alternatively, substance induced. A lot of drugs can mess with your NMDA receptors enough to induce psychosis. Whether that manifests as religious, grandiose, persecution or mixed delusions is something we can’t know, at this point. But yeah, I’d say that they were definitely suffering from some form of neuromodulatory failure of postsynaptic excitability.”
I decided not to ask. Psychotic was close enough, as far as I was concerned. I didn’t need to understand the mechanics of it, thank goodness.
“You say McKinnon’s getting that DI Philips guy and his team to look into local patients who’ve been prescribed antipsychotics?” Shay asked thoughtfully. “Not a bad idea, but what if we’re dealing with someone who only moved here recently or who isn’t registered with a doctor?”
I finished off my coffee and shrugged unhappily. “Then we’re pretty much screwed when it comes to tracking them down that way. Unless you know an easy way of checking the whereabouts of hundreds of thousands of people from all over the UK easily.” Shay seemed to be considering the suggestion seriously.
“No.” he finally decided, “Even if I found them all, someone would still need to check their registered addresses to see if they’d moved or not. And what if they’re not even listed? It would be a total waste of time and manpower, sorry.”
My mouth quirked at the reflexive little apology there. It certainly wasn’t Shay’s fault that some things were beyond even his ability to resolve easily. He seemed to be ruminating on something else by then though.
“I doubt your killer had any accomplices,” Shay said, his gaze seemingly focused
