Saturday, January 19, 2013

LMAYQ: Why do I like that?

Again it is time for me to answer some questions. As always, these are real true 'search terms' that have resulted in some one finding The Cellular Scale. While some questions (like 'how do you build a model of a neuron') are answered by this blog, the ones I answer is these LMAYQ posts are almost certainly not. All the questions and answers in this series can be found in the Let Me Answer Your Questions index.

Drawing by Grave Unicorn
1. "Why do I like ketamine so much?"

This is actually a pretty interesting question. Ketamine is a psychoactive drug known to cause hallucinations and feelings of dissociation, but it's not thought to be super-addictive in the same way that heroin or cocaine are thought to be. So why do you like it?

First let me get a 'safety warning' out of the way. Even though research is currently being conducted to investigate ketamine as an acute anti-depressant and to investigate its possible role in neurogenesis, it is not all considered a safe drug. It can seriously damage your urinary system for one thing, and probably damages your brain. Don't take it.

Ketamine (source)

Having said that, ketamine might give you a 'good feeling' because it is a partial agonist (meaning helps activate) the dopamine D2 receptor and the serotonin 5-HT2 receptor. In 2002, Kapur and Seeman published a paper showing that ketamine (and PCP) affects the dopamine and serotonin system by binding to these specific receptors. However dopamine is a confusing molecule and the idea that ketamine activates the D2 dopamine receptors does not necessarily mean 'pleasure.'

A classic test of 'wanting something' in rats is the self-administration paradigm, where rats can press a lever and get a dose of some drug or an electrical stimulation directly into the brain. A recent paper by De Luca and Badiani (2011) shows that rats will self administer ketamine when given the chance.
Interestingly, they found that the amount of self-administration was much higher when they took the rat out of its cage and put it somewhere new for the self-administration session. When the rat was allowed to self-administer ketamine in its home cage it just didn't give itself as much.

So your 'liking' of ketamine might have to do with where you are when you do it.
Kapur S, & Seeman P (2002). NMDA receptor antagonists ketamine and PCP have direct effects on the dopamine D(2) and serotonin 5-HT(2)receptors-implications for models of schizophrenia. Molecular psychiatry, 7 (8), 837-44 PMID: 12232776

De Luca MT, & Badiani A (2011). Ketamine self-administration in the rat: evidence for a critical role of setting. Psychopharmacology, 214 (2), 549-56 PMID: 21069515

2. "What do neurons like?"

This question cracks me up because it reminds me of two personal anecdotes. First it reminds me of one of my professors who just can't stand when people say "the neurons behaved this way or that way." The idea being that behavior is a thing animals do, not a thing that neurons do. I basically agree that neurons don't behave per se, but I also don't really care if someone wants to 'be cute' by anthropomorphizing a cell.

Second, thinking about neurons 'liking' things or being happy reminds me of a yoga class when during the final relaxation segment, the teacher started saying things like 'You are happy. Your cells are happy, they are all smiling at each other.' It was hard for me to relax and let my cells smile at each other when all my willpower was being engaged preventing me from bursting into laughter.

Regardless, I will do my best to answer this question. I suppose, neurons 'like' glucose, which gives them energy. Other than that I don't think it's meaningful to talk about neurons liking things.

3. "Why do men like big women?" 

This is one of a long string of questions that resulted from me having the words 'small', 'men', 'like', 'big', and 'women' all in the title of a post. As you might imagine, this is far from the worst 'search term' that has dropped people onto that page.

And believe it or not, this question has a scientific answer.

A paper this year by Swami and Tovee (2012) investigates the influence of stress in men's judgement of women's bodies. They found that men who were stressed for just 15 minutes (by being forced to give a speech explaining how suitable they are for a job) found 'bigger' women more attractive than the men who were not stressed did.

Poor guy, if only he had a nice motherly type to cook him a pie. (source)
The 'explanation' could be (though this is speculation, of course) that bigger women represent more 'security.'
"The Environmental Security Hypothesis [15][16] suggests that, when socioeconomic or individual conditions are threatening or uncertain, individuals will prefer others with more mature physical characteristics, including a heavier body size, compared to their preferences in non-threatening conditions. This is because physical maturity is associated with the ability to handle threatening situations and because more mature physical features may communicate attributes such as strength, control, and independence during periods when such qualities should be most desired [15]." -Swami and Tovee (2012)
This paper is covered in more detail over at TryNerdy, and the paper is open access so you can read the source material if you want.
Swami V, & Tovée MJ (2012). The impact of psychological stress on men's judgements of female body size. PloS one, 7 (8) PMID: 22905153

© TheCellularScale


  1. The 'what do neurons like' question reminds me of Sebastian Seung's silly talk at sfn a few years ago where he proposed the hedonic neuron hypothesis: that neurons were competing for dopamine. I, thankfully, think that went nowhere.

  2. Haha, what do neurons like! Such a funny question.

  3. Oh yoga! I once took a yoga class. I hated it. The instructor would say things like "breathe to the back of your lungs. Most people breathe only to the front of their lungs, but try to breathe to the back of your lungs." What the hell does that mean...