Graduate Program in Neuroscience, Western University, London, Ontario, Canada.
Center for Functional and Metabolic Mapping, Robarts Research Institute, Western University, London, Ontario, Canada.
J Neurophysiol. 2021 Jul 1;126(1):330-339. doi: 10.1152/jn.00078.2021. Epub 2021 Jun 16.
Faces are stimuli of critical importance for primates. The common marmoset () is a promising model for investigations of face processing, as this species possesses oculomotor and face-processing networks resembling those of macaques and humans. Face processing is often disrupted in neuropsychiatric conditions such as schizophrenia (SZ), and thus, it is important to recapitulate underlying circuitry dysfunction preclinically. The -methyl-d-aspartate (NMDA) noncompetitive antagonist ketamine has been used extensively to model the cognitive symptoms of SZ. Here, we investigated the effects of a subanesthetic dose of ketamine on oculomotor behavior in marmosets during face viewing. Four marmosets received systemic ketamine or saline injections while viewing phase-scrambled or intact videos of conspecifics' faces. To evaluate effects of ketamine on scan paths during face viewing, we identified regions of interest in each face video and classified locations of saccade onsets and landing positions within these areas. A preference for the snout over eye regions was observed following ketamine administration. In addition, regions in which saccades landed could be significantly predicted by saccade onset region in the saline but not the ketamine condition. Effects on saccade control were limited to an increase in saccade peak velocity in all conditions and a reduction in saccade amplitudes during viewing of scrambled videos. Thus, ketamine induced a significant disruption of scan paths during viewing of conspecific faces but limited effects on saccade motor control. These findings support the use of ketamine in marmosets for investigating changes in neural circuits underlying social cognition in neuropsychiatric disorders. Face processing, an important social cognitive ability, is impaired in neuropsychiatric conditions such as schizophrenia. The highly social common marmoset model presents an opportunity to investigate these impairments. We administered subanesthetic doses of ketamine to marmosets to model the cognitive symptoms of schizophrenia. We observed a disruption of scan paths during viewing of conspecifics' faces. These findings support the use of ketamine in marmosets as a model for investigating social cognition in neuropsychiatric disorders.
面部对于灵长类动物来说是至关重要的刺激物。普通狨猴（）是研究面部处理的有前途的模型，因为这种物种具有类似于猕猴和人类的眼球运动和面部处理网络。面部处理在精神神经疾病（如精神分裂症（SZ））中经常受到干扰，因此，在临床前重现潜在的电路功能障碍很重要。N-甲基-D-天冬氨酸（NMDA）非竞争性拮抗剂氯胺酮已被广泛用于模拟 SZ 的认知症状。在这里，我们研究了亚麻醉剂量的氯胺酮对狨猴在观看面部时的眼球运动行为的影响。四只狨猴在观看同种个体面部的相位随机化或完整视频时接受了系统氯胺酮或生理盐水注射。为了评估氯胺酮对观看面部时扫视路径的影响，我们在每个面部视频中确定了感兴趣区域，并对扫视起始位置和这些区域内的着陆位置进行了分类。在给予氯胺酮后，观察到对鼻子区域的偏好超过了眼睛区域。此外，在生理盐水但不在氯胺酮条件下，扫视起始区域可以显著预测扫视着陆区域。对扫视控制的影响仅限于所有条件下扫视峰值速度的增加，以及在观看随机视频时扫视幅度的减少。因此，氯胺酮在观看同种个体面部时会导致扫视路径的显著中断，但对视动控制的影响有限。这些发现支持在狨猴中使用氯胺酮来研究神经精神疾病中社交认知的神经回路变化。面部处理是一种重要的社交认知能力，在神经精神疾病（如精神分裂症）中受损。高度社交的普通狨猴模型为研究这些损伤提供了机会。我们给狨猴施用亚麻醉剂量的氯胺酮来模拟精神分裂症的认知症状。我们观察到在观看同种个体面部时扫视路径的中断。这些发现支持在狨猴中使用氯胺酮作为神经精神疾病中社交认知的模型。
