Table 2.
Summary of study interventions and cognitive outcomes in schizophrenia.
| References | Measure used for outcome assessment. | Result |
|---|---|---|
| Zhou et al., 2023 (Zhou et al., 2023) | Cambridge Neuropsychological Test Automated Battery | No significant improvement |
| Lisoni et al., 2022 (Lisoni et al., 2022) | Brief Assessment of Cognition in schizophrenia | Significant improvement in digit sequencing |
| Bulubas et al., 2021 (Bulubas et al., 2021) | 1. Penn-CNB 2. Penn Conditional Exclusion Test 3. Penn Letter N-Back test (PLNB) 4. Penn Word Memory Test (PWMT), 5. Penn Face Memory Test (PFMT), 6. Short Visual Object Learning Test (volt) 7. Emotion identification (EMI) |
Executive functioning and delayed memory improvement in the sham arm. |
| Chang et al., 2020 (Chang et al., 2020) | 1.Mini-Mental State Examination 2. The Trail Making Test 3. Wisconsin Card Sorting Test 4. Tower of London-Drexel University Test (TOLDXtm 2nd edition) |
No Significant improvement in cognitive symptoms |
| Smith et al., 2020 (Smith et al., 2020) | 1. Repeatable Battery for the Assessment of Neuropsychological Status 2. MATRICS™ Consensus Cognitive Battery (MCCB™) |
There was no immediate change; however, after two weeks, there was a significant improvement in the processing speed and MATRIC composite score. |
| Weikert et al., 2019 (Weickert et al., 2019) | 1. Weschler Test of Adult Reading (WTAR) 2. Wechsler Adult Intelligence Scale 3rd Edition (WAIS-III) 3. MATRICS™ Consensus Cognitive Battery (MCCB™) |
Beneficial effects on cognition in schizophrenia that transfer to other prefrontal dependent cognitive domains. |
| Jeon et al., 2018 (Jeon et al., 2018) | MATRICS™ Consensus Cognitive Battery (MCCB™) | Improvement in MCCB working memory and overall score. |
| Gomes et al., 2018 (Gomes et al., 2018) | MATRICS™ Consensus Cognitive Battery (MCCB™) | No significant improvement |
| Smith et al., 2015 (Smith et al., 2015) | MATRICS™ Consensus Cognitive Battery (MCCB™) | Significant improvement in composite score and working memory |
| Lindenmayer et al. 2019 (Lindenmayer et al., 2019) | MATRICS™ Consensus Cognitive Battery (MCCB™) | Significant improvement in the working memory domain and no change in the composite score. |
| Mellin et al. 2018 (Mellin et al., 2018) | 1. Cognitive function (BACS) 2. Brief assessment of cognition in schizophrenia |
There was no significant difference among the three groups. However, effect size analysis indicated that tDCS had the most critical effect size, with a baseline vs. post cd of 1.5. |
| Koops et al., 2018 (Koops et al., 2018) | Stroop test and trail making test | No significant benefit was measured by the Stroop test. Significant benefit as measured by TMT B after one week. |
| Palm et al. 2016 (Palm et al., 2016) | 1. Self-Ordered Pointing Task (SOPT) for WM, 2.Trail-Making Test (TMT-A) for processing speed, and TMT-B for executive functioning. |
The participants generally improved in reaction time for the cognitive tasks (TMT-A and TMT-B); these improvements were not influenced by their group, nor did they differ when considering the interaction of time and group factors. The working memory task (SOPT) showed no improvements or changes across any conditions. |