## 3 Results
\begin{table}
\begin{tabular}{c l l l l l l} \hline \hline
**Studies/ Criteria** & **Design,** & \multicolumn{1}{c}{**EEG NFB**} & \multicolumn{1}{c}{**Target**} & \multicolumn{1}{c}{**Measured**} & \multicolumn{1}{c}{**Results**} & \multicolumn{1}{c}{**Limitation**} \\ \cline{4-6}
**Criteria** & **Population** & \multicolumn{1}{c}{**Control Group**} & \multicolumn{1}{c}{**Frequency**} & \multicolumn{1}{c}{**Results**} & \multicolumn{1}{c}{**Limitation**} \\ \hline \multirow{4}{*}{[PERSON] [PERSON] and [PERSON] (2002) [34]} & Case study & & & Reduction of uncontrollable & \\  & HY = ND & 4+ month & \(\uparrow\) SMR & movements, & Case study, \\  & N = 1 & 42x 1 h; & (13–15 Hz) + breathing & Descriptive & improvement of walking & descriptive \\  & Avg. age = 47 & 1–2x/week & 1–2x/week & & walking & results, double \\  & 100\% F & ND & exercises & & unaided, & blind research \\  & 10–20 system & & & & control of & \\  & FCz—PCz & & & & freezing of gait & \\ \hline \hline \multirow{4}{*}{[PERSON] et al. (2012) [35]} & RTC & & & AIMS, UPDRS, HY— & Age differences, small sample \\  & HY = ND & & & & nonsignificant & size, small \\  & N = 9 (4/5) & 12–14 weeks; & \(\uparrow\) 8–15 Hz; \(\downarrow\) & AIMS, PD home diary, & results; & dyskinesia \\  & Avg. age. = 55.83 & 24x 30 min NFB & 4–8 Hz; \(\downarrow\) & & Significant & difference \\  & 55.56\% F & SHAM group & 23–34 Hz & & UPDRS & results in qEEG & between \\  & 10–20 system & & & & measurements & experimental \\  & C3–C4 & & & & in spectral EEG & and control \\  & & & & topography & groups. \\ \hline \hline \multirow{4}{*}{[PERSON] et al. (2014) [8]} & RTC & & & & No long-term \\  & HY = 1.5–2 & 2.5 weeks & & & follow-up of the \\  & N = 16 (8/8) & 3x/week & \(\uparrow\) beta1 & & statistically \\  & Avg. age. = 74.7 & 30 min & (12–15 Hz); \(\downarrow\) & & Biodex test & \\  & 50\% F & SHAM and & theta (4–7 Hz) & (level 8), BBS & significant & with more \\  & 10-20 system & & & & results & severe disease \\  & O1–O2 & & & & & to the HY scale. \\ \hline \hline \multirow{4}{*}{[PERSON] et al. (2021) [36]} & Pilot study & & & UPDRS-III & No long-term \\  & HY = 2 & & & & mixed results, \\  & N = 2 (1/1) & 2 consecutive & & & \\  & Avg. age = middle & days & SMR & & second day & participants; a small number \\  & 50 & 2x NFB 1 h & (12–17 Hz) & & improvement in & of participants, \\  & NP\% F & ND & & & rigidity and & a small number \\  & 256-channel system & & & & walking. & of NFB. \\  & C3–C4 & & & & & EEG training \(\uparrow\) & \\  & RTC & & & & BBS; \(\downarrow\) TUG; & Gender \\  & HY = 2–3 & & & & beta regulation & differences, no \\  & N = 21 (7/7/7) & 2 weeks & SMR (13–15 Hz) & & UPDRS III, & (enhancement); \\  & Avg. age = 61.72 & 5x NFB; 13 min & + breathing & & Bulg, TUG, & Multimodal \\  & 76.19\% F & SHAM group & exercises & & HRSD & group: \(\uparrow\) & participants. \\  & ND & & & & theta regulation & \\ \hline \hline \end{tabular} Note: HY—Hoehn–Yahr scale, ND—no data, N—number of participants, avg. age. = age average of the participants, RTC—randomized control study, SHAM—SHAM control group, EEG NFB—electroencephalograph based neurofeedback, SMR—sensorimotor rhythm, UPDRS—MDS Unified Parkinson’s Disease Rating Scale, BBS—Berg balance scale, TUG—Timed up and go test, AIMS—Modified abnormal involuntary movement scale, HRSD—Hamilton depression scale, Biodex test—center of gravity control test, \(\uparrow\)—increase, \(\downarrow\)—decrease.  
\end{table} 
Table 2: Key results and methodologies of reviewed studies. [PERSON] and [PERSON] (2002) [34] presented one of the first studies on the use of EEG biofeedback for movement disorders, specifically in a patient with dystonia and Parkinson's disease. Their six-month case study involved a 47-year-old woman who completed 30 one-hour NFT sessions, aiming to increase sensorimotor rhythm (SMR, 13-15 Hz) activity and practice diaphragmatic breathing. Motor improvements were observed after 12 sessions, with control over freezing episodes restored by the end of training. [PERSON] et al.