Fresnoza Shane, Büsche Kjell, Kern Maximilian, Christova Monica, Freigang Sascha, Mosbacher Jochen A, Grabner Roland H, Ischebeck Anja
Department of Psychology, University of Graz, Graz, Austria.
BioTechMed, Graz, Austria.
PLoS One. 2024 Dec 2;19(12):e0312919. doi: 10.1371/journal.pone.0312919. eCollection 2024.
Reasoning is the ability to formulate inferences or conclusions from available information. The two major types, deductive and inductive, are thought to rely on distinct cognitive mechanisms and recruit separate brain areas. Neuroimaging studies yield mixed results; some found the left inferior frontal gyrus (IFG) activations for deductive reasoning and the left dorsolateral prefrontal cortex (DLPFC) for inductive reasoning. This assumption was put to the test in the present study. In two double-blinded, sham-controlled experiments, high-definition transcranial direct current stimulation (HD-tDCS) was used to systematically explore the left IFG's and DLPFC's causal role in deductive and inductive reasoning. Participants with no formal training in logic judged deductive and inductive arguments before and after 10 minutes of anodal, cathodal, or sham tDCS of the left IFG (Experiment 1, n = 20) or left DLPFC (Experiment 2, n = 21). Left IFG anodal tDCS impairs reaction times (RTs) for easy categorical (p = < .001) and propositional (p = .025) deductive arguments and the accuracy for easy inductive propositional arguments (p = .003). Meanwhile, regardless of the active stimulation conditions, left DLPFC tDCS shortens RTs (anodal: p = < .001, cathodal: p = .014) and increases accuracy (anodal: p = .029, cathodal: p = .001) for difficult categorical inductive arguments, but decreases accuracy (anodal: p = .027, cathodal: p = < .001) for difficult propositional inductive arguments. The overall results showed a partial dissociation of the left frontal lobe areas subserving the two types of reasoning and argument difficulty-dependent stimulation effects. This study extends knowledge of the neural basis of reasoning and hopefully inspires interventions that could augment reasoning impairments associated with normal aging and brain lesions.
推理是根据现有信息形成推论或结论的能力。演绎推理和归纳推理这两种主要类型被认为依赖于不同的认知机制，并涉及不同的脑区。神经影像学研究结果不一；一些研究发现左额下回（IFG）在演绎推理时被激活，而左背外侧前额叶皮层（DLPFC）在归纳推理时被激活。本研究对这一假设进行了验证。在两项双盲、假刺激对照实验中，使用高清晰度经颅直流电刺激（HD-tDCS）系统地探究左IFG和DLPFC在演绎推理和归纳推理中的因果作用。在对左IFG（实验1，n = 20）或左DLPFC（实验2，n = 21）进行10分钟的阳极、阴极或假tDCS刺激前后，让没有接受过形式逻辑训练的参与者对演绎和归纳论证进行判断。左IFG阳极tDCS会损害简单分类（p = <.001）和命题（p =.025）演绎论证的反应时间（RTs），以及简单归纳命题论证的准确性（p =.003）。同时，无论刺激条件如何，左DLPFC tDCS都会缩短困难分类归纳论证的RTs（阳极：p = <.001，阴极：p =.014）并提高其准确性（阳极：p =.029，阴极：p =.001），但会降低困难命题归纳论证的准确性（阳极：p =.027，阴极：p = <.001）。总体结果表明，支持这两种推理类型的左额叶区域存在部分分离，且存在论证难度依赖性刺激效应。本研究扩展了对推理神经基础的认识，并有望启发相关干预措施，以改善与正常衰老和脑损伤相关的推理障碍。
