visual stimuli and fear

[gib65]

Hello,

 

Please have a look at the diagram below.

 

I made this. I'm trying to illustrate the pathways visual information takes in the case of fear stimuli. For example, seeing sharp fangs and piercing eyes.

 

I'm trying to demonstrate how the fear reaction occurs independently of the actual seeing of the stimulus. I want to know if my diagram is correct. I'm trying to dispell the natural assumption that we get scared at sights like sharp fangs and piercing eyes because they look scary. Since the fear occurs (at the amygdala) prior to seeing the stimulus (in the visual cortex), it can't be the sight of the stimulus that scares us - it can only be a correlate.

 

I would like to know if the diagram looks accurate to you.

[tomgwyther]

AFAIK, the signals from the optic nerves enter the thalamus first, and then the occipital lobe (Visual cortex)

Then sent through the rest of the cerebellum via the limbic system. from there we decide whether or not the image is scary and take appropriate action. i.e. get scared. This process requires memory and judgment handled by the higher functioning parts of the brain.

Not to be confused with the startle response which seem to be what your diagram indicates.

[gib65]

AFAIK, the signals from the optic nerves enter the thalamus first, and then the occipital lobe (Visual cortex)

Then sent through the rest of the cerebellum via the limbic system. from there we decide whether or not the image is scary and take appropriate action. i.e. get scared. This process requires memory and judgment handled by the higher functioning parts of the brain.

Not to be confused with the startle response which seem to be what your diagram indicates.

 

Yes, it's the startle response that I'm thinking of as associated with fear. But this "deciding whether or not the image is scary" sounds more like what we do when we get the impression that the image "looks" scary. This can be done in the absence of the actual feeling of fear, such as when we look at the poster for a horror movie.

[LawfulBlade]

gib65, I learned about what you're talking about in neuroscience classes over ten years ago. At this point, however, it's now known to not be the case. A ton of data have accumulated against the idea you just stated, but I'm including a link to the most comprehensive review of all of these data. It's just around a year old:

 

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3025529/

 

You can access the full article, rather than just the abstract, which is really necessary, given the methods and logic in this particular article. It's not that the original studies have been invalidated: they were performed in rodents, and rodents still have these features. Primates, however, do not. Rapid, coarse processing through the cortex is sufficient to explain the phenomenon, and is backed by all studies to date. The article I linked will, in addition, goes into tremendous detail on anatomical considerations, current EEG/MRI data, and studies performed with human ablation subjects (like from trauma, stroke, lupus, etc). It's a great read, and I hope you enjoy!