All Things Scary

All Things Scary

http://weknowyourdreams.com/fear.html

Fear is defined by dictionary.com as “an unpleasant emotion caused by the belief that someone or something is dangerous, likely to cause pain, or a threat”. Animals and humans experience fear in many different ways. Fear is an evolutionarily useful emotion- it can prevent a creature from coming in contact with something potentially harmful or engaging in a behavior that is dangerous and may cause injury or death. Studies have shown there are different ways to experience fear. Sometimes, there are fears that are predisposed to a species, while other studies have shown that fear can be learned. The processes linked to these fear responses may be very complex and involve many different areas of the brain.

Below, a video describes a study which attempted to determine the functions of the brain during courage. Participants were exposed to a fearful stimulus (a snake) and their brain activity was monitored. Activity was found in the subgenual anterior cingulate cortex and right temporal pole when fear was increased. Also, the temporal lobe structures, such as the amygdala, were active when fear was increased and the participant 'overcame' their fear. 

http://www.sciencedirect.com/science/article/pii/S0896627310004678

(The video shows the procedure around 1:30 and the breakdown of brain areas around 3:20)

Often, it is assumed that the amygdala is the source of fear in animals. Dr. Joseph LeDoux argues that the assumption that the amygdala controls fear is incorrect. His work shows that the amygdala plays a role in response to threats, but that this does not equate to the emotion of fear directly stemming from the amygdala. LeDoux argues that studies with humans have shown that while responses the threats may be affected by loss of amygdala, yet those people can still feel fear. He hypothesizes that the feeling of fear is a result of many different processes in the brain including attention, perception, memory and arousal, and also thinks that fear requires self-awareness (LeDoux, 2015).  This argument is interesting considering the numerous studies that have been conducted on animals for whom self-awareness is not assumed.

https://www.huffingtonpost.com/joseph-ledoux/the-amygdala-is-not-the-b_b_7977278.html

Some studies have shown a predisposed ability of animals to show fear to a stimulus. One such example was done with turkey chicks who, with no prior experiences to base their fear upon, reacted with fear when a object cast a shadow on them. This demonstrated the chicks predisposed fear of predators who would come from above and cast a shadow (Tinbergen, 1948).

https://ferrebeekeeper.wordpress.com/category/turkeys/page/3/

This type of fear can often be seen in pets. Often, you may notice young rodents will be fearful of large shadows or loud screeches when you first bring them home. This tendency is due to their predisposed fear of things that could be seen as predatory. The ferrets at the Oshkosh zoo demonstrate this behavior. Though they are pets and have not needed to avoid predation, they still will cower or run away when a large shadow passes over them. This fear has no backing- they have never been harmed by the thing producing the shadow. In other cases, fear can be learned through observation.

 http://www.animalplanet.com/pets/other-pets/5-ferrets/

Another study, this time using rhesus monkeys, demonstrated the learning of fear through observation. The researchers found that the monkeys could learn to fear snakes, without having prior experience, just by watching a video of another monkey reacting to a snake with fear (Cook & Mineka, 1990). This study shows the ability of animals to learn to fear something without actually experiencing the consequences. Learning to fear potential dangers without experiencing them could be a very big help evolutionarily. This could greatly improve survival of the animals who are able to learn and avoid things that caused others of their species harm. 

https://thehumanevolutionblog.com/2014/10/08/are-humans-predisposed-to-fear-snakes/

Social learning may be one of the ways that fear is passed through a species from generation to generation and could contribute to the survival (or extinction) of species depending on their ability to learn from others. Social learning is a difficult thing to study- often there are many ways an animal could be performing a behavior and it cannot be assumed they are learning. Regardless, when studying fear, it is interesting to consider the brain's role in fear, the different ways fear can appear, and how these fears could determine the fate of a species. 

References

• Dictionary.com
• LeDoux, Joseph. “The Amygdala Is NOT the Brain's Fear Center.” Psychology Today, Sussex Publishers, 10 Aug. 2015, www.psychologytoday.com/blog/i-got-mind-tell-you/201508/the-amygdala-is-not-the-brains-fear-center.
• Tinbergen, N. (1948). Social releasers and the experimental method required for their study. Wilson Bulletin, 60, 6-51.
• Cook, M., & Mineka, S. (1990). Selective associations in the observational conditioning of fear in rhesus monkeys. Journal of Experimental psychology: Animal Behavior Processes, 16(4), 372-389.