Examination of the Effect of Complex Visual Stimulus on Balance, Attention and Short-Term Memory in Patients with Persistent Postural Perceptual Dizziness

Persistent postural perceptual dizziness (PPPD) is a chronic functional vestibular disorder characterized by the persistence of one or more complaints of imbalance, dizziness, and non-spinning vertigo for three months or longer. Exposure to moving or complex visual stimuli is one of the three main situations that aggravate PPPD symptoms. This study aimed to examine the effects of complex visual stimuli on balance, attention and short-term memory in PPPD patients. Twenty patients with PPPD, 20 patients with idiopathic chronic unilateral vestibular hypofunction (CUVH) and 20 healthy individuals (control group) were included in our study. Visual vertigo analogue scale, dizziness disability inventory and Beck anxiety scale were applied to all individuals. Then, the participants were shown the optokinetic stimulus as a complex visual stimulus. Stroop t-BAG form, digit span test, and balance error scoring system (BESS) were applied before and after the complex visual stimulus. No difference was detected between the groups in terms of Stroop t-BAG form scores (p>0.05). There was no difference between the groups in terms of forward and backward digit span scores (p>0.05). However, complex visual stimulation was determined to decrease the back digit span test scores in PPPD patients (p=0.046). Before the complex visual stimulus, the firm ground tandem stance error score in the BESS test of both the PPPD and CUVH groups was higher than the control group (p =0.010 and p=0.003). After the complex visual stimulus, an increase was observed in the BESS error scores of the PPPD and CUVH groups (p<0.05). Complex visual stimulation affects balance skills in PPPD and CUVH patients. However, visual working memory is affected only in PPPD patients after complex visual stimuli. Therefore, complex visual stimuli may affect not only balance skills but also cognitive skills in PPPD patients. Key Words: Persistent postural perceptual dizziness, vestibular system, cognitive functions, stroop, digit span