Author Archives: Mehtab Manji

If the Heat waved, would you wave back?

  1. Salut!

If you’ve read my first post, you already know I am not your common happy blogger… But don’t get me wrong, I LOVE PARIS and I’m having the time of my life!!!

So lets get started…

I landed in Paris a day before the start of the program, and stayed with my dad’s friend for a day. When I entered their house, I was shocked to see no central air conditioning unit, but I assumed they obviously have ACs in the bedrooms because isn’t it a necessity? Little did I know, ACs are not common in Paris, in fact, they are not “needed” because the weather is so pleasant. Coming from America, I guess you can say I am spoiled because I am used to being surrounded by air conditioning all day, everyday. From my home, to my car, to my school – it’s everywhere. Hence, I wasn’t consciously thinking of it as luxury but rather as a necessity.

Honestly, this is so relatable…

At Cite Universitaire, my room has a huge window that I normally keep open so that the temperature stays moderate, but even then I could not adjust to this non-AC lifestyle. After a few sleepless and irritated nights, I went and bought a fan; this was no doubt one of my best investments. That night, I slept like a baby.

The peaceful nights did not last very long though… This week, my third week in Paris, has been incredibly hot. The temperature went up the roof – about 35°C (95°F) average for the week. The authorities in France officially laid out precautions and plans to minimize the affects of this heatwave (thelocal.fr).

The temperature spiked around the 17th of June and returned to bearable temperatures on Friday!

 

As a person who already doesn’t like summer because of the unbearable heat, this was a very tragic week. I was sweaty, upset, annoyed, stressed, and tired all the time.

Those few moments of air conditioning or fan in some metros or restaurants were the moments I cherished. Coming back to my room everyday wasn’t something I looked forward to. Even my incredible fan wasn’t of much help with this heat.

With all these emotions and feelings I was going through, I wondered how this is affecting my brain (mainly because I needed a scapegoat to blame my unproductivity on – don’t judge).

As I dug deeper into the literature, I stumbled upon this article by Jiang et al. (2013) that investigated the effects of hyperthermia on human cognitive performance, using functional magnetic resonance imaging (fMRI), which is a technology used to detect changes in the brain activity during a specific task. Hyperthermia (HT) is defined as a condition in which the body temperature rises above normal. They wanted to see if cognitive performance would deteriorate in the HT condition compared to the control and how brain activity will be different in both groups.

The participants were divided into two groups; the HT group and the control group. To stimulate effects of hyperthermia, the HT group was in a hot chamber (50°C) with a thermal heated suit on for 30 minutes prior to the fMRI scanning. In the control group, the participants followed the same procedure but the chamber temperature was kept normal (21.5°C). The researchers precisely looked at brain activity during a visual short-term memory (VSTM) task to examine the participants’ cognitive performance. Previous research has shown three brain regions, dorsolateral prefrontal cortex (DLPFC), inferior intra-parietal sulcus (IPS), and intra-occipital sulcus (IOS), are involved in maintaining visual information for a short period of time (Todd et al. 2004, Grimault et al. 2009), hence, the researchers in the current study looked specifically at changes in activity in these three brain regions during the VSTM task.

In this task, the participants were presented with 60 trials of probe and target images, alternatively. Their task was to press “yes”, if the probe and target images were identical, or press “no” if the probe and target images were not identical. The participants in both the groups, control and HT, were in the fMRI scanner while they performed this task. Analyzing the behavioral results, they found that even though the HT group did not differ in accuracy compared to the control, they took much longer to answer the questions. On the neural side, fMRI results indicated increased brain activity in areas that are involved in visual memory task, as mentioned earlier (DLPFC and IPS). They saw that the brain was much more active during the heat exposure condition even though the participants were slow in the task, which shows that their visual short-term memory function was weakened. The researchers suggest that the increased brain activity could be due to more attention and cognition being used to do the same task compared to the control condition.

This study shows that exposure to very high temperatures, even for 30 minutes, can actually affect your cognitive performance. Your brain will need to use more energy and require longer time to perform a basic task. This study does an amazing job connecting the behavioral aspect with the neural aspect under heat stress in humans. It also uses well-defined brain regions, which makes it clearer to identify the changes in brain activity. However, they fail to discuss why they did not see changes in activity in IOS, one of the regions they evaluated during the tasks, even though previous research had shown that the IOS is involved in the visual memory task. More research needs to be done to identify how other cognitive activities may be affected due to heat, because global warming is a real problem and we see more and more incidents of heat waves occurring all over the world. If we better understand the impacts of heat on human brain and function, we can probably identify ways to prevent or rescue the damage caused by heat exposure.

Stay cool 🙂

Mehtab Manji

 

 

 

 

References:

Grimault S, Robitaille N, Grova C, Lina JM, Dubarry AS, Jolicoeur P (2009) Oscillatory activity in parietal and dorsolateral prefrontal cortex during retention in visual short-term memory: Additive effects of spatial attention and memory load. Hum Brain Mapp 30: 3378–92.

Jiang Q, Yang X, Liu K, Li B, Li L, LI M, Qian S, Zhao L, Zhou Z, Sun G (2013) Hyperthermia impaired human visual short-term memory: An fMRI study. Int J hyperthermia 29(3): 219-24

Local, The. “Paris: Authorities Trigger Emergency Heatwave Plan as Capital Continues to Sizzle.” The Local. The Local, 20 June 2017.

Todd JJ, Marois R (2004) Capacity limit of visual short-term memory in human posterior parietal cortex. Nature 428:751–4.

Images:

1, 4) http://www.welikela.com/heat-wave-memes-about-los-angeles/

2) http://www.funnycaptions.com/tag/summer-heat-jokes/4/

3) https://www.timeanddate.com/weather/france/paris/historic

 

Have you been scammed, yet?

Bonjour!

Many of you may know that Paris is a hub for street scams. From the typical “bracelet scam” to the shell game scam is found at every tourist spot in Paris. Let me back up a little and explain what this particular scam entails. There is a ball under one of the three cups in front of you. The challenge is to point out the cup under which the ball is after the dealer has shuffled them around.

The participant puts in foot on the cup and pays the dealer 100 euros

Although it seems oddly “easy” to identify the right cup, this game is a trap for tourists who are unaware of the scam. To make the tourist even more susceptible, the dealer has a group of people around him pretending to be participants, when in reality they are all in on the scam. These people bet money and win double of what they bet, they clap and encourage vulnerable tourist to bet money, and most importantly, they tell you that you are “obviously” going to win if you pick that specific cup. But guess what? No one wins- because its all just a fraud that many people fall for, their first time visiting Paris.

Video 1

It was my second day in Paris, when I went to the Eiffel tower with a couple of my friends. Soon after we got off the metro, we saw a crowd gathered around. We peaked through and saw this game being played. At first sight, my impression was “ofcource it’s a scam,” but when I watched it for a couple of minutes and saw people actually winning money, I was intrigued to believe that winning is an actual possibility. Although I didn’t bet any money, my friend was willing to just go for it and I also supported that idea. It was obvious that she was right, the ball should have been under that cup because we saw it with our own eyes! The dealer picked up the cup, and to our surprise, the ball was not there. We freaked out and felt vulnerable. She wanted the money back so she bet money again, and this time we were surer that the ball is under the cup she picked; however, just like the previous time, she lost the money. We couldn’t fathom how he did that, how he made the ball disappear but there was more to that game than what met the eye. After my friend researched the trick behind this game, we went back to the Eiffel tower to comprehend what really happened. This time, knowing the trick, it wasn’t very difficult for me to understand what was happening. The dealer picked up the ball in a subtle manner while he shuffled the cups around, so no matter which cup you picked you were going to lose your money.

I was really mad and tried to spoil his game by telling people its scam. Interestingly, one of the “pretend players” comes up to me and tells me that I should keep my mouth shut and leave if I didn’t want to play.

This whole incident got me thinking, why do people fall for this scam? Why do we take such risks despite the possibility of adverse consequences? My curious neuroscience side wanted to see how the brain is involved in such behavior. A study called, “Individual differences in susceptibility to investment fraud” by Knutson and Samanez-Larkin (2014) investigated susceptibility to investment fraud via the differences in physiological, neural, and behavioral data between victims and non-victims of investment frauds. They hypothesized that (1) victims will show increased preference for risky gambles (increased activity in Nucleus Accumbens or decreased insula activity); (2) victims will show reduced behavioral control especially when incentives are high (decreased ventrolateral prefrontal cortical activity). They assessed the first hypothesis using the gambling task. In this task, victims and non-victims, in each trial, viewed a gamble cue, waited as the wheel spun, observed and reported the outcome (selecting “gain” or “loss” presented randomly on either side of the screen), and saw trial and cumulative earnings. Basically, they were assessing if victims prefer low probability but high magnitude risks compared to non-victims.

Gambling task

They found that victims showed no preference to the type of gamble but non-victims preferred positive skewed (low probability of a high gain) over negative skewed (low probability of a large loss) gamble. To test their second hypothesis, the participants took the Monetary Incentive Delay Inhibition task. In this task, they were presented with incentives and tested on their ability to control impulses.

Monetary Incentive Delay Inhibition task

The behavioral results show victims failed to inhibit their responses when the gain was larger compared to non-victims. The neural results show decreased activity in the right ventrolateral
 prefrontal cortex of victims than in non-victims when considering negative skewed gambles (exp. 1) or when anticipating larger gains (exp. 2).

This data shows that fraud victims lose impulse control when they see the potential of a large gain. If the possibility of gaining is low, but the magnitude is high (like double the money in the shell game scenario), some people are willing to take the risk because they are prone to riskier gambles and lack impulse control when the gain is large. Even though this study does a good job explaining differences in vulnerability amongst people, it fails to explain if this individual difference can be explained by predisposition or significant differences in brain structure. They mention the role of nucleus Accumbens and anterior insula in their hypothesis but fail to mention these brain areas in any results or conclusions they drew. Although more research need to be done to explain the actual causation of differences in risky behavior in humans, this study demonstrates a strong correlation between decreased activity in the ventrolateral prefrontal cort
ex and victim to investment fraud, which relates to my observation that some people fail to inhibit their impulses when the reward is large.

Watch out for those scams, fellas.

Until next time, Au revoir!

 

References

Knutson B, Samanez-Larkin G (2014) Individual Differences in Susceptibility to Investment Fraud. Research on Fraud.

Image 1 and video 1 taken by me.

Image 2 and 5: Creative commons

Image 3: Wu CC, Bossaerts P,  Knutson B (2011) The affective impact of financial skewness on neural activity and choice. PloS one 6(2):e16838.

Image 4: https://www.researchgate.net/profile/Gang_Chen34/publication/221781705/figure/fig2/AS:267537376084038@1440797289961/Figure-1-Modified-monetary-incentive-delay-MID-task-Each-trial-began-with.png