Author Archives: Shawn

Amazing Memories and the Potential Future of Memory Research.

memory

Imagine being able to remember everything you have ever said or done. If you’re like me, I barely remember what I said two days ago let alone everything I’ve ever said. Though, I’m sure it would get rather annoying to our partners if that were the case. There are those rare individuals who have a gift (or curse) which is called “Highly Superior Autobiographical Memory” or HSAM for short. These individuals have the uncanny ability to remember more personal and emotional memories. Memories referred to as episodic memories.

Episodic memories are just that, memories that have personal meaning that are tied to emotion. The other type of memory is called semantic memory. Semantic memories are not tied to emotions, they’re just facts. So if I ask you, who was the first President of the United States? Or, what is the capital of the United Kingdom? There probably is not much if any emotional ties to these answer, yet you were able to remember them. This is your semantic memory. Don’t worry, there are semantic memory champions as well:

[youtube]https://www.youtube.com/watch?v=oY6DznRX6L0[/youtube]

So, it seems as though you can’t have it both ways, but that you can at least practice really hard and become good at your semantic memory. But how does memory really work? There are two ways that we’ll talk about it, the first will be cognitive and the other will be more neuroscience.

Cognitive psychologist use the Modal Model of Memory, which follows a path from sensory input, to sensory memory, to working memory, and then into long-term memory (LTM). Working memory is sometimes referred to as “short-term memory” though that term is not used as much anymore. From working memory, it has three places to go, the memory can decay, it can move into long-term, or the individual has to keep the memory active through rehearsal. Working memory has a capacity though, it can hold 7 items (plus or minus 2) within. It also has a time limit which is roughly 30 seconds, though if you believe old Hollywood movies, it’s more like 5 minutes. Once the memory goes into LTM, cognitive psychology doesn’t go into how it is stored, just mainly into how it is retrieved. For this, we turn to a more neuroscience approach:

According to Neuroscientists, forming a LTM starts this chain of neurons connecting that otherwise don’t normally connect. The example used above is building a bridge between two areas that weren’t previously connected. So, let’s take the example of the rats, when the tone is played, they receive a shock. After the first time, neurons are being connected to tell the rat, this tone equals a shock. After it is done a few more times, the connection between the neurons is stronger (long-term potentiation) and the signal is able to travel quicker when recalled.

This is only at the cellular level and does not fully explain the entire purposes, but it goes far enough for our purposes in this post because there has been a study done recently that challenges this school of thought. Neuroscientists have recently found that memories may actually exists within the neurons themselves. The implications of this, if supported, has not only the potential of changing the way in which we think about memory, but it could mean hope for those suffering from illnesses like PTSD and Alzheimer’s.

For PTSD sufferers, this could potentially mean that we could do a “Sunshine of the Spotless Mind” and zap the neurons and get rid of the memories in which the individuals are having the problems with. For Alzheimer’s, this could mean that their memories are truly lost and that they could, with further research, regain some of the previously thought lost memories. The research is really still new and definitely needs further testing to gain any sort of support and I remain skeptical as one critic suggested that the “results were observed in the first 48 hours after treatment, a time when consolidation is still sensitive.” Consolidation refers to the process in which working short-term memory becomes long-term memories.

As this is the last post that I’ll probably be making on this blog, I leave you with this scene of Eternal Sunshine of the spotless Mind:

[youtube]https://www.youtube.com/watch?v=2ke2HjqVXfc[/youtube]

False Confessions: How you might confess to a crime you never committed.

Remembering a Crime

I’m a computer guy. So when I’ve thought of memory in the past, I’ve always explained it in those terms; working memory is sort of like RAM and Long term memory is like your hard-drive. This isn’t completely accurate of course, but it’s easier for those that do not understand memory to conceptualize. The problem with that analogy is that one cannot fully appreciate the complexity of memory, though I would suggest it is a bit more accurate than the filing cabinet analogy in that with a hard drive all the pieces of information are fragmented into bits and are spread out onto the disk. When you understand the complex nature of memory, you can then understand how it could create a false memory with just a mere suggestion.

There have been numerous studies that look at this. One of the biggest researcher in the area of false memories is Dr. Elizabeth Loftus of the University of Washington. She has done a number of different studies but one of her more famous is where she successfully implanted a false memory into participants about getting lost in a mall  in which an elderly person found them and reunited them with their family. Out of the 24 individuals, 7 of them remembered this false event. She is often credited with starting this research. This suggests that when a person is fed a false memory by those whom they trust, in this case stories from their parents, they are susceptible to recalling things that simply never happened. Another experiment that Loftus conducted had participants view a car accident in which they were told to recall certain facts about what happened. Participants were asked one of two questions, either they were asked how fast the cars were going when they hit each other or they were asked how fast they were going when they smashed into each other. The “hit” group estimated the speed being 34 miles per hour while the “smashed” group estimated that the cars were going about 41 miles per hour. The participants would even then recall seeing things at the scene that did not exist such as glass all over the road (there wasn’t).This is referred to as the misinformation effect.

[youtube]https://www.youtube.com/watch?v=qQ-96BLaKYQ[/youtube]

This all suggest how inaccurate our memories can be when we try to remember specific events and how easily we can succumb to the mere suggestion of another individual with a bit of authority (e.g. parents). After all, we didn’t evolve to remember every detail of an event. It’s not very important to remember the color of the eyes of the lion that’s chasing after you or how many stripes a zebra has. It’s important to remember that big cats can kill you and zebras are a good source of sustenance.

So then, what happens if we take this understanding and throw it into criminal investigations? I present to you, the case of Michael Crowe:

[youtube]https://www.youtube.com/watch?v=z0tdOWZK4AA[/youtube]

Let’s be clear, these detectives were not merely suggesting that he had committed the murder of his sister, they went in already having decided that this 14 year old was guilty and they were determined to make him confess. They obviously succeeded. This was a much higher stakes event than what Loftus had done with her participants; one could rightfully argue that this could have an impact on false memories. The article at the top of the page brings into the discussion an experiment  that was conducted where participants were given a false story of them having committed a crime that led to police involvement. They modeled their experiment after Loftus’ work that was described above, in that they asked the parents to write about the participants past and then they threw in the false story. After a time, they were asked to remember events from their childhood and 70% of the participants (yes, 70%) remembered the false crime as if they had actually committed the crime. They didn’t just remember the event, they created elaborate stories about it.

This begs the question of how many innocent individuals have confessed to things that they have never done. In 2003, false confessions were the number one reason for wrongful convictions. Since 2000, there have been about 317 exonerations made by new DNA testing. About 30% of those (roughly 95 people) made false confessions and 18 of those were on death row.

Questioning suspects is a needed part of the criminal justice system. However, with what we have discussed, we can see how much we are susceptible to false memories.  Those doing the questioning must be trained to do so in a way that reduces the risk of false confessions because they have real and severe consequences.

 

 

 

Elizabeth Loftus’ TEDtalk
[youtube]https://www.youtube.com/watch?v=PB2OegI6wvI[/youtube]

Ouch! My Visual Cortex Hurts.

dress

If you have been on a social media site in the last few days then I’m sure you have probably seen the image above before. The biggest question on the internet has been, which do you seen, black-and-blue or white-and-gold? The picture showed up randomly on Tumblr from a dress maker in India and since then it has taken the internet by storm. This entire issue is all thanks to our top-down processing.

We must first realize that color is a subject perception. Meaning that what I would call red, doesn’t necessarily mean that another would call red (or whatever color). This is the same with all sensory information; for example, I am a super taster, which means that I have more bitter receptors on my tongue than most other individuals and what others may taste as only slightly bitter, I’ll be in the trash can trying to get the remnants off with a fork. The difference with vision is that we take in additional contextual information such as shadows.

[youtube]https://www.youtube.com/watch?v=XGG01xTYSoo[/youtube]

Shadows play a huge part in how we perceive many things visually such as motion and color. The video shown above shows a few examples of just how much our visual perception relies on shadows. This is purely top-down processing. We see the shadow and expect that the color is actually lighter than it is. This is referred to as color constancy. Color constancy is a Gestalt principle which basically suggests that the context in which we view an object influences our perception of that object.

With this in mind we must then understand what top-down processing is. To put it simply, top-down processing is how we form expectations of the world around us and how magicians, for example, are able to fool us. Now, look at the picture below, do you see anything? This is a good example of top-down versus bottom-up processing. Bottom-up processing just see’s the image as a bunch of dots whereas once I tell you that there is a Dalmatian in the picture with its nose to the ground that it then becomes a top-down issue. If you look close enough, it’s as though you can actually see the lines which make up the dog, but look again, they’re not there. It’s all your brain connecting the dots and creating the object out of the minimal amount of information given.

So this goes to a larger question of how we perceive our world. How could a simple dress fool the way in which we see? I think the biggest thing we must realize is that color isn’t a physical thing that actually exists. Color is our brains interpretation from data it receives from our eyes which is simply waves of radiation bouncing off of the objects that we are looking at. Simply put, our brain creates color.  A fact that I have found interesting from my very first Psychology class is that since vision is simply light waves bouncing off of an object, when we think of color, the object is every color EXCEPT the color we see. For example, I have a green apple sitting on my stand right now. As light waves hit the apples skin the light is absorbed by the skin of the apple, except the green waves are bouncing off and traveling to my eye which then my brain interprets into “green”. The apple is not actually green; green is the only color it is NOT. With this in mind we can see how easily our brains can be fooled into seeing something that doesn’t actually exist, especially when we through shadows into the mix as well.

[youtube]https://www.youtube.com/watch?v=wiMDO2yXCsk[/youtube]

So then back to the original dress debate. The answer is that the dress is really blue and black. The reason 3/4ths of those who look at it see white and gold is because of the light behind the dress. It’s tricking your brain into thinking that the dress is in shadow so it then must be lighter than what are eyes are seeing. The question I have now though, is how the other 25% of people (I’m included) didn’t see white and gold. Even after I knew the answer and knew why it was this way, I still fail to see white and gold. Perhaps that is a question for a later post. I leave you with this ASAP Video on the matter.

[youtube]https://www.youtube.com/watch?v=AskAQwOBvhc[/youtube]

Marijuana Use Hastens Onset of Schizophrenia

Marijuana use

[youtube]https://www.youtube.com/watch?v=4LScZZOkeIs[/youtube]

Schizophrenia is one of the most well-known and perhaps the most misunderstood mental disease to the layperson. However, with the new knowledge stated in the above article and the new laws legalizing the use of Marijuana, we must understand what we may be getting ourselves into.

Now, in the interest of full disclosure, I am in favor of the legalization of Marijuana so long as there are other arguably worse drugs that are legal…and no, I do not partake and I’ve never had a desire to; which means I do not have a vested interest in the ultimate outcome of this policy.

When I mention Schizophrenia, most individuals I talk to bring up the movie A Beautiful Mind and bring up hallucinations. They also typically throw in the “Crazy” word at some point with the occasional “really” in front of it. While this can be true for some individuals, what is talked about less is the cognitive aspect of it all. After all, for these people THIS is their reality; it’s not just “something in the heads” to them, these things really do exist. Working in a mental health facility, I’ve witnessed what these individuals have to go through weekly.

[youtube]https://www.youtube.com/watch?v=aS_d0Ayjw4o[/youtube]

Schizophrenia affects both males and females equally. Though it is found in all socioeconomic groups, it shows up more within the lower levels. This doesn’t necessarily mean that they start off poor, but for reasons we will discuss later, they may just end up in a worse position. Additionally, those of African descent are more likely to receive the diagnosis. The typical onset is in the early 20’s for males and later 20’s for females, though the range is between the ages of 18 and 30.

The effect on a person’s life could be dramatic based upon when they have their first episode. If a person is 17, they’re typically still in high school whereas a 30 year old is probably already done with college (unless you’re me). Those suffering from this disease find it hard to concentrate for obvious reasons and often get distracted from whatever they are doing. Their cognitive functioning is harmed because of this. An article done by Ronan O’Carroll suggested that verbal memory showed the greatest sign of impairment with these patients. Since most of education is verbal (lectures), one can only imagine how difficult it would be to get through school!

So, let’s get back to the original article which tells us that those individuals who use marijuana are likely to have their first episode about 2 years earlier than those who do not. If this is true, then the age range could potentially be 16 – 30 as typically marijuana users start in their mid to late teens. They also suggest that its use may trigger schizophrenia in those individuals that wouldn’t develop it otherwise.

As adolescence is a critical time for development within the brain. Potentially, the author suggests, the use of the drug could have an effect on the maturation of certain functions within the brain. Some may argue that 2 years is not a whole lot of time, however, 2 years of extra development could mean a lot. Two years could mean that the person has a diploma and is that much more employable and it could even mean finishing college completely!

One of the biggest complaints about the article is that the individuals who did the study did not just look at Marijuana use; in fact, the words that were used were “Alcohol” and “Other illegal drugs. They stated in the title that it was just about Marijuana. The article goes on to state that substance abusers in general were more likely to have their first symptoms 2 years earlier. This leaves a huge question within my mind about the validity to the claim that it’s Marijuana because it could potentially be any other illegal drug.

Ultimately, if these results are true for Marijuana use, the potential consequences could be devastating on an individual level. It is clear that this research needs to be refined to distinguish between the different types of drugs there are. If this holds true for Marijuana, then we must prepare for the potential consequences. For example, funding mental health hospitals to better deal with these issues, though we should be funding mental health more to begin with as it is sorely lacking and often overlooked. We must educate the populace of the potential harmful effects that this could have on younger individuals. This will not guarantee anything, of course, but it will allow individuals to make a more educated decision.