The following is a fantastic article that highlights some of the lesser known facets of anxiety and how it alters our functioning on every level: http://www.spring.org.uk/2013/10/8-fascinating-facts-about-anxiety.php
I especially appreciated the description of how perception is changed. While the author focused on sensory input, the filtering system of stimuli is also severely compromised. At a certain level of escalation, the fight or flight response is interested solely on survival. The frightened brain assesses every input as either neutral or threatening. Anything that falls into the former category is discarded while anything threatening is escalated into life-or death proportions.
Consider how this might impact an argument with a loved one. The brain believes it is under attack and will therefore do anything to avoid further assault. It is unable to hear contextual information that might bring perspective and all positives are omitted. The only information getting through is anything with a flavor of offense. And of course, the objective of the entire exchange will be to attack or seek distance, permitting verbal lashings to achieve this end. At this point, the other person will most likely escalate, rightfully bewildered and by the dark cloud of hurtful words lingering in air.
If you suffer from this phenomenon, you do not have to sit back and watch anxiety wreak havoc on your life. Knowledge is power. One can learn to recognize the various levels of fear so the corresponding impacts can be adjusted for. Techniques are available to promote timely de-escalation, and awareness can create a process to identify thought distortions and increase the potential for healthy responses. The key is to recognize that worry and anxiety are not helpful- they are compromising. As soon as you are on alert, there is an ability to literally change your mind.