Tyburski Ernest Marek, Zawadzka Ewa, Bober Adrianna, Karabanowicz Ewa, Podwalski Piotr, Samochowiec Jerzy, Michalczyk Anna, Sagan Leszek, Jansari Ashok, Mueller Shane T, Harciarek Michał, Misiak Błażej, Lutkiewicz Karolina, Wietrzyński Krzysztof, Kucharska-Mazur Jolanta, Reginia Artur, Mak Monika
Department of Health Psychology, Pomeranian Medical University in Szczecin, Broniewskiego 26 Str., 71-457, Szczecin, Poland.
Department of Clinical Psychology and Neuropsychology, Maria Curie-Skłodowska University, Lublin, Poland.
BMC Psychiatry. 2025 Mar 25;25(1):282. doi: 10.1186/s12888-025-06597-7.
Psychopathological symptoms appear important for cognitive functions in schizophrenia. Nevertheless, the factors and their impact on relationships between negative or disorganization symptoms and verbal fluency are still debatable. The preliminary objective of the study was to compare verbal fluency, including clustering and switching as cognitive strategies, executive functions, and processing speed between individuals with schizophrenia (SZ) and healthy controls (HC). The main aim of the study was to investigate mediation models and identify whether relationships between negative and disorganization symptoms and verbal fluency in schizophrenia are mediated by cognitive flexibility and processing speed.
Semantic (animal and fruit) and phonemic (letter k and letter f) fluency tasks, the Berg Card Sorting Test (BCST), and the Color Trails Test (CTT) were administered in the SZ group (n = 108) and a matched HC group (n = 108). The Positive and Negative Syndrome Scale (PANSS) was applied to measure psychopathological symptoms in schizophrenia patients.
SZ produced fewer words, had larger cluster size, and fewer switches in semantic fluency than HC. Moreover, the SZ group had longer completion time in CTT 1 and CTT 2 and higher percent of perseverative and non-perseverative errors in BCST than HC. Three mediation models demonstrated good fit indices, suggesting that processing speed and cognitive flexibility were significant mediators for relationships between: (1) psychopathological symptoms and productivity or semantic clustering in animal fluency; (2) negative symptoms and productivity in semantic or phonemic fluency; and (3) disorganization symptoms and productivity in semantic fluency.
Individuals with schizophrenia are characterized by a specific performance profile on verbal fluency tasks. They manifest poor productivity and problems using cognitive strategies for semantic fluency. Referring to executive functioning, schizophrenia patients exhibit decreased cognitive flexibility, problem-solving, and formulating concepts, as well as slow processing speed. It was found that processing speed and cognitive flexibility may be understood as the neuropsychological mechanisms modifying the relationships between negative symptoms, disorganization symptoms, and semantic and phonemic fluency. Therefore, these results provide a foundation for including cognitive flexibility and processing speed in cognitive remediation for schizophrenia patients.
精神病理症状对精神分裂症的认知功能似乎很重要。然而，这些因素及其对阴性或紊乱症状与言语流畅性之间关系的影响仍存在争议。该研究的初步目标是比较精神分裂症患者（SZ）和健康对照者（HC）在言语流畅性方面的差异，包括作为认知策略的聚类和转换、执行功能以及加工速度。该研究的主要目的是调查中介模型，并确定精神分裂症中阴性和紊乱症状与言语流畅性之间的关系是否由认知灵活性和加工速度介导。
对SZ组（n = 108）和匹配的HC组（n = 108）进行语义（动物和水果）及音素（字母k和字母f）流畅性任务、伯格卡片分类测验（BCST）和颜色轨迹测验（CTT）。应用阳性和阴性症状量表（PANSS）来测量精神分裂症患者的精神病理症状。
与HC相比，SZ在语义流畅性任务中产生的单词更少，聚类规模更大，转换次数更少。此外，SZ组在CTT 1和CTT 2中的完成时间更长，在BCST中的持续错误和非持续错误百分比高于HC。三个中介模型显示出良好的拟合指数，表明加工速度和认知灵活性是以下关系的重要中介因素：（1）精神病理症状与动物流畅性中的生成能力或语义聚类之间的关系；（2）阴性症状与语义或音素流畅性中的生成能力之间的关系；（3）紊乱症状与语义流畅性中的生成能力之间的关系。
精神分裂症患者在言语流畅性任务中具有特定的表现特征。他们在语义流畅性方面表现出较差的生成能力以及使用认知策略存在问题。在执行功能方面，精神分裂症患者表现出认知灵活性、解决问题和形成概念的能力下降，以及加工速度缓慢。研究发现，加工速度和认知灵活性可被理解为调节阴性症状、紊乱症状与语义和音素流畅性之间关系的神经心理机制。因此，这些结果为将认知灵活性和加工速度纳入精神分裂症患者的认知康复提供了依据。
