Past research highlights the potential contribution of conventional fluorescent lighting to anxiety symptoms in agoraphobia. Such type of lighting usually pulsates in brightness between a maximum and a minimum twice with each cycle of alternate current electricity supply (e.g., 100Hz). In return, this pulsation causes the cells in the retina and the lateral geniculate nucleus (a brain relay center for sensory inputs from the retina) to fire.
More importantly, conventional fluorescent lighting is found to affect the nervous system and produce bodily symptoms, such as increased heart rate, that feel more unpleasant for individuals with agoraphobia than to those without the condition. Past studies even find that a substantial portion of patients with agoraphobia report having panic attacks after exposure to conventional fluorescent lighting.
Reference:
Hazell, J., Wilkins, A.J., 1990. A contribution of fluorescent lighting to agoraphobia. Psychological Medicine 20, 591–596