Gating of sensory information differs in patients with interstitial cystitis/painful bladder syndrome

Abstract

Purpose: Altered sensory processing in interstitial cystitis/painful bladder syndrome cases may result from a deficiency of the central nervous system to adequately filter incoming visceral afferent information. We used prepulse inhibition as an operational measure of sensorimotor gating to examine early pre-attentive stages of information processing in females with interstitial cystitis/painful bladder syndrome and healthy controls.

Materials and methods: We assessed prepulse inhibition in 14 female patients with interstitial cystitis/painful bladder syndrome and 17 healthy controls at 60 and 120-millisecond prepulse-to-startle stimulus intervals. We evaluated group differences in prepulse inhibition, and relationships between prepulse inhibition, neuroticism and acute stress ratings.

Results: Patients showed significantly decreased prepulse inhibition at 60 and 120-millisecond prepulse intervals. The prepulse inhibition deficit was related to acute stress ratings in the patients. However, increased neuroticism appeared to mitigate the prepulse inhibition deficit in those with interstitial cystitis/painful bladder syndrome, possibly reflecting greater vigilance.

Conclusions: Compared to healthy controls, female patients with interstitial cystitis/painful bladder syndrome had decreased ability to adequately filter incoming information and perform appropriate sensorimotor gating. These results suggest that a possible mechanism for altered interoceptive information processing in interstitial cystitis/painful bladder syndrome cases may be a general deficit in filtering mechanisms due to altered pre-attentive processing.

Figure 1

Unmodulated acoustic startle response magnitude. Values are means (with standard error bars) for each startle alone trial throughout the experimental session. Ln μV = natural log transformed microvolts

Figure 2

Prepulse inhibition of the acoustic startle response. Values are estimated means (with standard error bars). Greater prepulse inhibition is indicated by a more positive difference score. The right axes shows percent change derived from the log-transformed difference scores. Significance is indicated for group differences in percent PPI. Ln μV = natural log transformed microvolts.