The biology of anxiety can be understood as being comprised of two flows of information. The first flow originates in the [amygdala](https://en.wikipedia.org/wiki/Amygdala), and the second in the cerebral cortex. Here's an excellent diagram from [[Rewire your Anxious Brain]] that breaks down the flows of anxiety:  The amygdala pathway is the one that goes: Real World Stimulus -> Thalamus -> Amygdala -> Anxiety Response The cortex pathway is the one that goes: Cortex -> Amygdala -> Anxiety Response. The cortex pathway may or may not be triggered by real world events. ## Notes on the Amygdala Because all anxiety flows through the amygdala, it's useful to understand some special attributes of the amygdala that contribute to anxiety. Let's focus on three such attributes. The first is that the amygdala has special direct connections to the hypothalamus, which in turn releases the hormones cortisol and adrenaline to generate the [[Fight-flight-freeze response]]. This direct connection allows the amygdala to _respond extremely quickly_ to stimulus. In fact, the amygdala can trigger this before the cortex realizes what's happening: > the amygdala receives information before the information can be processed by the various lobes in the cortex. This means the lateral nucleus of the amygdala can react to protect you from danger before your cortex even knows what the danger is. (p. 21) The second is that the amygdala has the ability to form [[Emotional memories]]. And the third thing is that the amygdala can actually influence our thoughts a great deal. > There are many connections from the amygdala to the cortex, allowing the amygdala to strongly influence the cortex’s responding on a variety of levels, while fewer connections travel from the cortex to the amygdala (LeDoux and Schiller 2009). (p. 25) ## Notes on the Cortex When it comes to the cortex, the biology is much more complex, so I wont even attempt to outline it here. With respect to anxiety, cortex based anxiety is much more familiar to us - it's what we traditionally think of when it comes to therapy. The authors of [[Rewire your Anxious Brain]] simplify cortex based anxiety largely to our faculties of interpretation and anticipation: > when we speak of the cortex pathway to anxiety, we’re generally focused on interpretations, images, and worries that the cortex creates, or on anticipatory thoughts that create anxiety when no danger is present. (p. 20). So all of those negative thoughts and images that lead to worry or the imagination of undesirable possibilities? That's the cortex. These thoughts generated by the cortex may be so powerful, we might start confusing them for reality, a phenomenon called cognitive fusion > cognitive fusion occurs when we get so caught up in our thoughts that we forget they’re merely thoughts. (p. 179). Cognitive fusion and other negative patterns of thought can actually trigger anxiety, or exacerbate an already anxious amygdala. Because both the cortex and amygdala can exacerbate anxiety triggered by the other, it is useful to familiarize yourself with techniques to calm both pathways, regardless of "who started it" (See [[Treatments for anxiety]]) Clipped from [Rewire Your Anxious Brain - Review](https://philipliao.com/books/rewire-your-anxious-brain) at 2021-02-26T19:23:50. #psychology