Physiotherapy and targeted rehabilitation are routinely performed in order to influence disorders of posture, gait and stability in Parkinson´s disease (PD), but their effects have been controversial (Keus et al. 2014; Walton wt al. 2014). Recently, several studies suggested that cognitive training can improve gait in patients with PD (Peterson et al. 2016, Heremans et al. 2013), similar to the effects seen in the elderly (Yogev-Seligmann et al. 2008; Amboni et al. 2013). Specific training programs including dual tasking with automatic verbal series, counting etc. have led to increased walking speed and improved stepping cadence, length, and duration in patients with dementia (Schwenk et al. 2010). However, since in advanced PD patients dual-task gait training has to be supervised by therapists, it is not a suitable type of therapy to be performed at home. Therefore, this study aims to verify and extend the encouraging results of the single study which showed a positive effect of cognitive function training on gait in PD (Milman et al. 2014) by exploring this effect in advanced PD patients, by assessing the effect on gait using more targeted clinical and instrumental evaluation, and by comparing two modes of therapy delivery, group and computer-based.

• Background: In a pilot study, Milman et al. 2014 showed that computer-based cognitive training focusing on executive function and attention performed at home might improve selected gait parameters in early patients with Parkinson´s disease (PD).
• Goal 1: To explore this effect in advanced PD patients
• Hypothesis 1: Effect of cognitive training focusing on executive function and attention will be detected also in advanced PD patients and this effect will be larger as compared to the results published by Milman et al. 2014.
• Goal 2: To verify the results published by Milman et al. 2014 using more targeted clinical and instrumental gait assessment, including dual-task gait evaluation as well as instrumental testing of turn fluency (Bertoli et al. 2019).
• Hypothesis 2: The results published by Milman et al. 2014 will be confirmed and an effect on dual-task gait and turn fluency will be shown.
• Goal 3: To explore the role of the form of therapy setting, i.e. whether group setting might increase the effect of cognitive training on gait as compared to individual cognitive training at home. Such results have been shown in the case of a physiotherapy intervention by King et al. 2015.
• Hypothesis 3: The effect of group cognitive training on gait will be larger as compared to individual dose-matched, computer-based cognitive training performed at home. However, it remains to be determined whether the effect size difference between the two groups will outweigh the advantages of tele-rehabilitation.
• Design: Randomised-controlled trial
• Interventions: experimental group: group cognitive training focusing on executive function and attention; control group: computer-based cognitive training focusing on executive function and attention performed at home. Intervention in both groups will be dose-matched (experimental: 60 mins, 2x/week, 12 weeks; control: 30 mins, 4x/week, 12 weeks)
• Follow-up: at 1 and 3 months time points.
• Power analysis results: at least 38 patients.

Inclusion Criteria:

• diagnosis of Parkinson´s disease (PD)
• PD duration ≥8 years
• mild cognitive impairment
• stable medication
• presence of freezing of gait according to the FoG-Q AND/OR Rapid Turns Test

Exclusion Criteria:

• dementia
• deep brain stimulation, pump therapy with Duodopa or Apomorphine
• severe fluctuations with ON state duration for less than 2 hours
• dopa dysregulation syndrome
• impulse control disorder
• untreated depression
• benzodiazepines except for single dose at night
• non-compliance
• inability to walk without support
• significant co-morbidities likely to affect gait, e.g., acute illness, orthopedic disease, significant visual problems, or a clinical history of stroke
• involvement in other treatment trials
• not meeting inclusion criteria

Participants are blinded to study hypothesis. Investigators are blinded to treatment group.