BioSci 41 Ch 8


List physiologic changes in brain region size associated with bipolar disorder.

  • The brain itself does not shrink when you have bipolar disorder, however there is an increase in ventricle size

    • Ventricle is the hollow part of your brain that has cerebrospinal fluid that bathes your brain and washes out toxins 

    • When the ventricle becomes enlarged the person often has less neural tissue as the brain does not get bigger to accommodate for this change



Define “hyperintensity signal”. What do hyperintensity signals reveal?

  • Hyperintensity signals are areas that appear brighter or lighter than the surrounding tissue on an MRI image of the brain (swiss cheese?) (losing brain matter) (Doesn’t mean it’s all a lost, if you are young your brain can reroute the connections to a large effect and lithium helps with this) 

    • Hyperintensity signals reveal areas of cell death 



Describe the role of the amygdala and parahippocampal gyrus region as it relates to emotion.

  • Both part of a large of the larger Limbic Gyrus section of the Limbic System 

    • hardwired to help you survive and ensure that you make good choices

  • The Amygdala being the emotional hub plays a part in forming memories with their strong correlation to each other. 

    • Both those at risk and bipolar disorder groups have a more active amygdala region 

    • Part of the severance loop 

    • Connected to cingulate cortex, cingulate cortex connect outside to frontal cortex and other regions

    • (Just recap of what we already know??)

  • The Parahippocampal

    • More active in those with bipolar disorder 

    • Part of the brain that is involved in determining emotion gist

      • Ex: Sarcasm or Effect



Evaluate research findings of amygdala activity in bipolar disorder. Hypothesize ways that age may influence this.


  • Where the brain is activated depends on age 

    • In younger children their left amygdala is more active 

      • It’s activation is similar when they see a fearful or happy face

    • Through the ages of 13-15, they use the amygdala less in response to facial expressions 

      • They are trying to figure out how it all works

    • When you are an adult the activation of the amygdala is moved over to the right amygdala 

      • This is because they have figured it out already 

      • They have seen plenty of people cry, fear, ect. so they don’t have to figure it out anymore




What does meta data on bipolar disorder and emotional recognition confirm? Describe how this relates to amygdala activity.



  • The data confirms that those who have bipolar disorder struggle more with recognizing emotions on a face

  • This lead to the overactive amygdala as their brain is attempting to process and understand the emotion, but since they have a hard time they cannot close the loop so it’ll be more active



Describe the role of the anterior cingulate cortex in bipolar disorder and evaluate fMRI findings of regional grey matter loss



  • The Anterior Cingulate Cortex 

    • Involved in separating emotions, identifying how one is feeling and plays its role in keeping our moods regulated 

    • This would mean that in those suffering from bipolar disorder their ACC could have deficient activity or connectivity. 

  • fMRI findings of grey matter loss

    • In adults who are living with bipolar disorder there is a decrease in the amount of right sided grey matter in the frontal cortex