Key Laboratory of Brain Functional Genomics (Ministry of Education and Shanghai), Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, and School of Life Sciences, East China Normal University, Shanghai, 200062, China.
Department of Physical Therapy, University of Maryland Eastern Shore, Princess Anne, MD, 21853, USA.
Mol Brain. 2021 Jan 15;14(1):13. doi: 10.1186/s13041-021-00732-7.
Cross-modal interaction (CMI) could significantly influence the perceptional or decision-making process in many circumstances. However, it remains poorly understood what integrative strategies are employed by the brain to deal with different task contexts. To explore it, we examined neural activities of the medial prefrontal cortex (mPFC) of rats performing cue-guided two-alternative forced-choice tasks. In a task requiring rats to discriminate stimuli based on auditory cue, the simultaneous presentation of an uninformative visual cue substantially strengthened mPFC neurons' capability of auditory discrimination mainly through enhancing the response to the preferred cue. Doing this also increased the number of neurons revealing a cue preference. If the task was changed slightly and a visual cue, like the auditory, denoted a specific behavioral direction, mPFC neurons frequently showed a different CMI pattern with an effect of cross-modal enhancement best evoked in information-congruent multisensory trials. In a choice free task, however, the majority of neurons failed to show a cross-modal enhancement effect and cue preference. These results indicate that CMI at the neuronal level is context-dependent in a way that differs from what has been shown in previous studies.
跨模态交互（CMI）在许多情况下都会显著影响感知或决策过程。然而，大脑采用何种整合策略来应对不同的任务情境，目前仍知之甚少。为了探究这一问题，我们检测了大鼠内侧前额叶皮层（mPFC）在执行线索引导的双选择强制任务时的神经活动。在一项要求大鼠根据听觉线索进行刺激区分的任务中，同时呈现一个无信息的视觉线索会显著增强 mPFC 神经元的听觉辨别能力，主要是通过增强对首选线索的反应。这样做还会增加表现出线索偏好的神经元数量。如果任务稍有变化，一个视觉线索（如听觉线索）表示特定的行为方向，mPFC 神经元通常会表现出不同的 CMI 模式，在信息一致的多感觉试验中，跨模态增强效果最佳。然而，在无选择任务中，大多数神经元都没有表现出跨模态增强效应和线索偏好。这些结果表明，神经元水平的 CMI 是依赖于情境的，这与之前研究中显示的结果有所不同。
