Ivan Pavlov is a name familiar to most, whether scientific expert or budding psychology student. Pavlov founded the basis of classical, or Pavlovian, conditioning, in which an animal or person learns to associate an initially meaningless stimulus in their environment with a stimulus that produces an automatic response, therefore eliciting the response when the newly meaningful stimulus is presented. Most famously, you might recognize Pavlov’s experiment where he conditioned dogs to associate sounds with the arrival of food, eventually producing a salivary response from the dogs with just the sound alone.
Following Pavlov, in 1919 a scientist named John B Watson became one of the first people to demonstrate fear conditioning: using Pavlovian conditioning to induce a fear response or a phobia. You may have heard of his notorious and ethically questionable “Little Albert” experiment, in which he induced phobias of rabbits and other normally pleasing objects in an infant through an association with loud, unpleasant noises.
Fear conditioning can be used for more than just questionable experiments on infants, though. In recent years, scientists have been using what we know about fear conditioning to study disorders like PTSD (Post Traumatic Stress Disorder), in hopes of finding new treatments.
PTSD, or post traumatic stress disorder, is a disorder where fear learned in a traumatic situation is triggered by seemingly neutral stimuli in ordinary, safe situations, producing detrimental physiological and behavioral responses. Studies have shown that the brain areas affected in PTSD – mainly the amygdala, hippocampus, and prefrontal cortex – are similar to the brain areas affected in rodents who have been fear conditioned. Evidence suggests that flawed synaptic plasticity, the ability for the brain to rewire itself, could be part of the cause of PTSD.
During fear conditioning, rodent’s brains rewire themselves to make a connection between a certain stimulus and a fear response. During extinction, the process in which a conditioned response to a stimulus goes away, the synaptic connections rewire themselves, no longer associating the certain stimulus to a fear response. In patients with PTSD, it is possible that the flawed synaptic ability hinders the fear response from being overwritten effectively. This results in the production of an otherwise unwarranted fear response in patients, when exposed to neutral stimuli.
By attempting to understand the synaptic basis for PTSD using animal models of fear conditioning, scientists can work toward developing new medications that effect chemical action at the synapses. Hopefully, these medications will be able to lessen the symptoms of PTSD in patients and eventually work toward more accessible treatment for flawed synaptic plasticity, and fear and anxiety disorders in general.
Heatherton, Todd, and Diane Halpern. “Chapter 6, Learning.” Psychological Science. By Michael Gazzaniga. 5th ed. New York: W W Norton, 2013. 222-37. Print.
Mahan, Amy L., and Kerry J. Ressler. “Fear Conditioning, Synaptic Plasticity and the Amygdala: Implications for Post Traumatic Stress Disorder.” Cell Press 35 (2012): 24-35. Web. 13 Oct. 2015.
A topic that has become more and more prevalent over the last few years is the effect of anxiety on attentiveness. How anxiety affects attention depends on the type of anxiety that is experienced. Most people experience state anxiety, in other words, a higher threat value is placed on a particular situation or stimulus. Feeling anxious during a very important midterm is an example of state anxiety. Another type of anxiety is trait anxiety, which is the tendency to focus one’s attention towards the stimulus causing the anxiety. In other words, to think only about the exam, instead of non-anxiety inducing stimuli.
Attention itself is composed of three independent networks: the alerting network, the orienting network, and the executive network. The alerting network is responsible for maintaining an appropriate level of sensitivity to the stimulus through activation of the right frontal and parietal areas of the brain. The orienting network attends to information coming from a specific stimulus among numerous sensory stimuli. This network is associated with activation in the superior parietal lobe, frontal eye fields, and temporoparietal junction. The executive network is responsible for conflict resolution and voluntary action control of the stimulus, and is related to the medial frontal areas of the brain, as well as the cingulate gyrus and lateral prefrontal cortex.
Two experiments were performed by the Department of Psychology and Physiology at the University of Granada and the Department of Neurology at Washington University School of Medicine to learn more about the relationship between these two different types of anxiety and attention. The first focused on trait anxiety, while the second focused on state anxiety.
The first experiment featured a group of individuals with either high or low trait anxiety, and another group of individuals with average trait anxiety. The two groups were made to perform various computer tasks that played to each specific network of attention. What the researchers found was that individuals with high-trait-anxiety had a more difficult time controlling interference in the computer tasks than those with low-trait-anxiety. However, the results of the alerting and orienting tasks were very similar for both groups. Those with high-trait anxiety had a difficult time responding to the task’s demands.
The second experiment also separated participants into two groups for anxious mood induction and non-anxious mood induction. One group was shown pleasant pictures and the other was shown unpleasant pictures, both groups were tasked with becoming emotionally involved in what they were seeing. In the group shown the negative stimuli (the unpleasant pictures), more emphasis was put on the lack of control over the negative circumstances represented in the image. The positive stimuli (the pleasant pictures) in the other group focused more on goal achievement. The individuals shown the negative stimuli revealed higher levels of anxiety than those shown the positive stimuli.
The results of the experiments revealed that both state and trait anxiety have a significant impact on attentional networks. State anxiety was found to have a greater impact on the alerting and orienting networks of attention, because they are more closely related to contextual sensitivity and vigilance processes. High state anxiety was found to be the result of a heightened response in the amygdala and superior temporal sulcus (regions activated during the assessment of valence facial expressions). It was also found that the executive network was less efficient in those with high-trait-anxiety than those with low-trait-anxiety because the executive network determines control, which is what those with high-trait-anxiety were lacking. High trait anxiety was related to a reduced prefrontal response (the region related to controlling complex processes). It was concluded that trait anxiety was responsible for a “reduced-general cognitive control capacity”.
1. Attention and Anxiety: Different Attentional Functioning Under State and Trait Anxiety
Memory has always been and still is a subject of interest for many neuroscientists. Whether it pertains to increasing memory or finding cures to neurodegenerative diseases such as Alzheimer’s, memory is always a topic of interest for neuroscientists. Recently, there have been studies conducted by both the Institute of Basic Science and Advancing Science, Serving Society (AAAS) that have found genes that are suppressed or inhibited that prevent the formation of these long term memories. Increased hippocampal activity also is shown to have treatments toward age related memory loss, which could relate to the genes found by the AAAS and the IBS.
The IBS Center, using a technique called Ribosome profiling, was able to analyze the hippocampus of a mouse model and showed that gene regulation actually suppressed the formation of memory. According to the article “When an animal experiences no stimulus in an environment the hippocampus undergoes gene repression which prevents the formation of new memories”, showing activity of the neurons help prevent this gene regulation which allows the formation of memory. Natasha Pinol from the AAAS also found a similar action in his studies however showed that one estrogen receptor actually helped regulate the memories after learning instead of inhibiting it, as Jun Cho for IBS has found.
Although these particular genes themselves might still have their purposes unknown to the world, these findings can definitely be used to help with age related memory loss such as Alzheimer’s disease. Through a study done at Northwestern University by Marla Paul, it is shown that decreasing certain activity and increasing other activity could lead to an increase in memory formation. Although they did not target the same genes that Cho and Pinol targeted, this really shows how much more we are learning about the hippocampus, as memory is formed through a moderation of genes.
– Albert Wang
Music has been scientifically proven as beneficial, having effects such as reducing stress, enhancing blood vessel function, improving sleep quality, and improving cognitive performance. However, one thing that music does not improve is one’s ability to focus. In a recent study conducted at Georgia Institute of Technology, researchers found that listening to music decreased the efficiency of remembering names.
Participants in this study were asked to match faces to names, a task that involves associative memory. In associative memory, a memory of an event or place is triggered by the recollection of something associated with it. Music is heavily involved in associative memory, which is why it can be upsetting to listen to certain songs if you have associated them with an ex-significant other. Much like other types of memory, associative memories are processed in the hippocampus of the brain.
Some participants completed this name-face test in silence, while others had non-lyrical music playing in the background. All age groups of participants agreed that the music was distracting from the test, but only the scores of the older adults were affected by it.
How would you feel if you had the choice of having billions of tiny robots injected into your body? A pretty unpleasant thought, am I right? What if I told you that these tiny robots could repair any mutation you may have in your DNA? Sound far-fetched? Well, scientists have been making huge breakthroughs in this! It’s called nanotechnology. These small robots are like tiny computers that are coded to attach to specific cells in your body and carry them from point A to point B. These tiny robots, 1-100nm in size (or 1 and 100 billionth of a meter!), are like transporters; they pick up the target cell at point A and move it to point B. Point B can be anything from the trash, (cell death) if the cell is not needed anymore, to another part of the body where the cell is needed. They also have the ability to reprogram a cell’s biology. If more of one cell is needed in a particular area it can bring that cell to the specified area and “tell” it to replicate. Basically, nanotechnology will eventually perfect every single cell in your body.
When I read a book, I get so immersed in the lives of the characters, I find myself anxious and on edge even though I know Katniss’ and Peeta’s tragic romantic life have no bearing on my reality. The fact that characters fabricated from mere words can have this effect on us is pretty incredible. Roel Willems and Annabel Nijhof thought so too apparently, as they recently published a study revealing the neurological effects of listening to audiobooks.
In the experiment, researchers had the subjects listen to chapters of several different audiobooks and recorded their neurological responses using functional Magnetic Resonance Imaging (fMRI). By analyzing the results, Willems and Nijhof determined that the subjects focused most on either the actions of characters or the feelings and intentions of characters. In the subjects that reported to prefer empathizing with the characters more, the fMRIs showed heightened activity in the anterior medial prefrontal cortex, whereas those that reported enjoying the action aspect of the story more had elevated activity in the motor cortex. More
Shaking hands dates back centuries, with many cultural explanations to back up the ancient customs. One study suggests that the true reason we shake hands is to find out what this new friend smells like. Why? Smell is a “socially significant chemical signal,” used by many other species in social interactions. The researchers conducting this Weizmann Institute study hypothesize that shaking hands is a subliminal way for us to register the smell of others, a primal social custom that survived evolution.
To begin the experiment, the researchers needed to determine if a handshake was enough to transfer detectable body odor. One subject wore a glove on their right hand and the other did not. When the glove was tested after the two subjects shook hands, odor residues containing “meaningful chemical signals” were found on the glove. The next step was to determine the amount of time (if any) spent sniffing the right hand after shaking hands. Around three hundred volunteers, unaware of the purpose of the experiment, were greeted by researchers via a handshake. Surveillance cameras in the room recorded the scene and showed how much time subjects spend sniffing their hands after the encounter. To ensure the subjects were actually subconsciously smelling their hands, nasal air flow was also recorded.
Did anyone read that article in BU today last week called “Untangling the Connectome?” In case you didn’t, here’s a brief synopsis. Dr. Kasthuri and his lab members are working on identifying the connections between the neurons in the human brain. This has been done before for C. elegans, which have only 302 neurons (compared to our 100 trillion). So, imagine how complex this project is and how much data is contained in one tiny slice of human brain?! In the article, Kasthuri said that a brain slice with the volume of “a millimeter cubed, at the resolution we would like, is about two million gigabytes of data” .That’s crazy. The Kasthuri lab implemented a clever method (Figure 1) to take images of 30 nm brain slices that provide the high resolution pictures they’re looking for.
Basically, the brain volume is immersed in plastic and cut with a diamond knife to ensure precision. Since the slices are somewhat floppy, they are collected in water then picked up by a conveyor belt. While on the conveyor belt, an electron microscope takes a quick shot of the brain tissue and next a collection of images is put together to create a accurate image of the initial brain volume. Methods can be used to break down the image of the brain volume into components such as axons, dendrites, etc. (Figure 2). Pretty cool, right? The implications of this research is that understanding the connections in our brain can teach us about brain development and memory functions.
The Human Connectome project at Mass General Hospital (MGH) is working on developing high resolution neuroimaging methods. They’re working on figuring out how varying white matter fiber connectivity correlates to brain function and how cytoarchitectonics (the pattern of neuron organization/density in different areas of the brain, used to decipher Brodmann’s areas in the brain) can influence brain connectivity . Methods they’re using include diffusion spectrum imaging (DSI), which is similar to diffusion tensor imaging (DTI) as both allow scientists to observe white matter connectivity since water diffuses parallel to white matter tracts. DTI measures the preferred and mean direction of the diffusion of water while DSI measures it in many different directions . Scientists at MGH are also working on developing tools for high angular diffusion imaging (HARDI), which “address[es] the challenge of imaging crossing fibers by applying a stronger magnetic gradient for a longer time and capturing many more images of diffusion in various directions” .
Researchers are hoping to find patterns of connectivity by deciphering how our 100 trillion neurons are linked. This information could help scientists better understand the roots of different neurological or neurodegenerative diseases where perhaps neural connectivity differs significantly. This is a challenging project but the results of it could be a major breakthrough for neuroscience.
~ Srijesa K.
When I read a book such as the one about the romantic life of Peeta and Katniss, I delve into the lives of the characters so much that I worry about myself because I relate myself to the characters’ fantastical lives. All readers face this and that is incredible. Neuroscientists like Roel Willems and Annabel Nijhof would completely agree. In fact, they recently published a study revealing the neurological effects of listening to audiobooks.
In the experiment, researchers had the subjects listen to chapters of several different audiobooks and recorded their neurological responses using functional Magnetic Resonance Imaging (fMRI). According to the results, the subjects focused mostly on either the actions of characters or the feelings and intentions of the characters. In the subjects that reported to prefer empathizing with the characters more, the fMRIs showed heightened activity in the anterior medial prefrontal cortex, whereas those that reported enjoying the action aspect of the story more had elevated activity in the motor cortex. Interestingly enough, the subjects that showed higher activation of the anterior medial prefrontal cortex displayed lower activation of the motor cortex when listening to the action parts of the stories. On the contrary, the subjects that engaged more with the actions of the story were applicable. This study provides neurological evidence that people relatively have different strengths and preferences when it comes to reading.
These findings imply this study could be used to know how people engage with literature. If we master what literature people prefer, we might be able to turn literature into a very fun activity. This research also offers further understanding on how we process language. As stated above, it shows that when listening to narration some people focus more on empathizing aspects while others focus more on the action-packed plot. Not only this teaches how we read books, but also how we process written and oral stories.
The Mentioned Experiment: http://neurosciencenews.com/literature-neuroimaging-psychology-1748/
Once upon a time, Rick went off to school in a bright sunny morning, and his parents waved goodbye before giving him his lunchbox. Then, he met his friends which he was excited for because together they will go to a bowling party. His friends were rather different because they were foreigners who would attend the Terran Orientation event since they don’t know anything about our homelan- I mean, homeworld.
I would certainly love to be in an alternate setting where the aliens as intelligence as us visit and coexist with us peacefully like how we deal with different nations. Unfortunately, some theorize that aliens would be more powerful than us leading to catastrophic events for humans like the relationship between the conquistadores and the Native Americans from the New World. However, that does not stop any writer from theorizing what would be the most fundamental requirements for an intelligent alien to travel throughout the galaxy. I present to you the top five list for an intelligently extraterrestrial life from the neuroscientist’s perspective.
- The alien must be able to hold objects. Without any way to hold objects by appendages, the alien cannot create technology to transport far away from space. It would be nearly impossible to travel to outer space without any protection because natural selection would almost never lead to intergalactic journeys since from the beginning the resources are available on the planet itself. Therefore, the alien has to learn to use inorganic tools to create a capsule-like setting to travel to outer space.
- The amount of resources are “just right” for the selective pressure to kick in. When the resources are ubiquitous for the alien, there is no need to be intelligent with problem-solving skills because the resources are there for you. Thus, there has to be a time for the alien when there is lack of resources leading to the emergence of analytical intelligence. Of course, the nutrients have to be rich enough for the aliens to survive.
- The alien has to be sociable with others. Teamwork is always a great method for problem-solving and according to neurobiology, asocial creatures tend to be less intelligent than social ones.
- The atmosphere of the environment which the alien breathes in has to be gaseous. The reason that a fish cannot travel to outer space is because it is too hard to create an aquatic environment in a space-vessel. Liquid is too dense and space-consuming to build an aquarium rocket. Gases on the other hand are readily available in some regions of space and the chemical formula is easier to synthesize when the alien is outside the terrestrial atmosphere.
- The alien has to be able to use ethical reasoning. What distinguishes a primitive life from more advanced ones is that some organisms use higher cognitive reasoning to figure out problems to escape unusual dilemmas. In fact, what makes humans different from other creatures is that we have prefrontal cortex, a region of the brain that governs ethical reasoning and executive functions. Ethical reasoning is what made us develop technologies to improve our civilizations, so it would not be surprising for an alien to have the same trait.
I must be careful in my argument because we have never seen any extraterrestrial life. What I will conclude, however, is that aliens whether they exist or not would probably face the same hardships like we did throughout history, leading to possible coexistence when we run across them.
-By Dongjun (Rick) Yoo
NE101 Class taught by Dr. Wayne Korzan, Fall Semester 2013
Facts on Animal Intelligence: http://interesting-animal-facts.com/Intelligent-Animals-Facts/Intelligent-Animals-Facts.shtml
Orangutan Spearfishing: http://primatology.net/2008/04/29/orangutan-photographed-using-tool-as-spear-to-fish/
Brain Rules by John Medina