A comparison of different types of prospective memory reminders in schizophrenia

Effect of cognitive style on time-based prospective memory

Field-independent and field-dependent individuals have different reference patterns and cognitive processing preferences. Field-independent individuals tend to rely on internal capabilities and use internal references to process information, while field-dependent individuals mainly rely on external references and focus on external information. Individuals with two cognitive styles have different attention patterns to perform time-based prospective memory (TBPM) tasks, with different effects on their TBPM performance. This study explored the influence of field-independent and field-dependent cognitive styles on TBPM. In Experiment 1, the attention load was manipulated by the difficulty of the ongoing task. The results showed that the field-independent individuals performed better than the field-dependent individuals only under a low-difficulty condition, indicating that the field-independent individuals had advantages in TBPM but were easily affected by the attention load. Experiment 2 further introduced external reminders to provide individuals with more external information and reduce individual attention consumption in internal time information processing to manipulate attention load. The results showed that external cues eliminated the difference between field-independent and field-dependent individuals in TBPM.

The benefits of emotionally salient cues on event-based prospective memory in bipolar patients and schizophrenia patients

Prospective memory (PM) refers to the ability to remember to carry out a delayed intention in the future. Evidence suggests that emotionally salient cues can enhance PM functions in healthy population, but whether the benefit exists in schizophrenia and bipolar patients remains unclear. This study aimed to examine and compare the potential enhancement effect of emotional PM cues in schizophrenia patients and bipolar patients. Twenty-eight clinically stable schizophrenia participants, 26 euthymic bipolar participants and 29 controls completed a computerized PM task involving PM cues with different types of valences (i.e., positive, neutral and negative). All the three groups showed better PM performance when negative PM cues were presented compared with positive and neutral PM cues. The sizes of the enhancement effects of negative PM cues were large (all Cohen's d ≥ 1.00) and comparable across three groups. Our findings suggested that patients with schizophrenia and bipolar disorders could benefit from negative PM cues to an extent similar to healthy individuals, thus extended the notion of psychosis continuum to the important area of emotion-cognition interaction.

Brief report: A randomized controlled trial of a compensatory cognitive training to improve prospective memory performance in people with schizophrenia or depression

People with schizophrenia or depression have prospective memory (PM) deficits, which affect their daily living. Given the paucity of research into training to correct PM deficits, we subjected a group of participants to a Chinese version of the PM module of the Cognitive Compensatory Training (CCT-C-PM) intervention to study its effect on their PM performance. Specifically, we independently randomized two diagnostic cohorts (schizophrenia and depression) into control groups (occupational therapy only) or experimental groups (CCT-C-PM and occupational therapy). The schizophrenia cohort had 17 participants in its control group and 23 participants in its experimental group. The depression cohort had 10 participants in its control group and 12 participants in its experimental group. The sociodemographic information of the participants was collected. Their symptoms and PM performances were measured at baseline and after treatment (after the completion of the CCT-C-PM intervention in the experimental group and the same timeframe in the control group). The treatment effects were examined by a repeated measure analysis of variance/analysis of covariance and a post hoc Scheffé test. The effect sizes (Cohen's d) of treatments against the controls were also calculated. There was no difference between the experimental and control groups in either cohort in terms of sociodemographic data, symptoms, and PM measures at baseline. The sex combination differed across the groups in the depression cohort. We found that the CCT-C-PM improved PM, especially event-based PM, for which large effect sizes were seen. The effect on time-based PM was unclear and requires future study. Our findings suggest that the CCT-C-PM is a viable training method for improving PM.

Prospective memory impairment in neurological disorders: implications and management

Prospective memory is a core neurocognitive ability that refers to memory for future intentions, such as remembering to take medications and to switch off appliances. Any breakdown in prospective memory, therefore, has serious implications for the ability to function independently in everyday life. In many neurological disorders, including Parkinson disease and dementia, prospective memory deficits are common even in the earliest stages and typically become more severe with disease progression. Consequently, clinical assessment of prospective memory is of critical importance. This article provides an overview of the various manifestations and neural bases of prospective memory deficits. To facilitate clinical decision-making, validated measures of this construct are identified and their suitability for clinical practice is discussed, focusing in particular on clinical sensitivity and psychometric properties. The article concludes by reviewing the approaches that can be used to rehabilitate different types of prospective memory impairment, and algorithms to guide the evaluation and treatment of these impairments are provided.