本實驗室主要運用心理物理學方法研究人類視覺過程以及相關的眼科與視光學臨床應用。近年的主要研究興趣在于知覺學習的心理物理學與腦機制，以及字符（漢字）識别的視覺機制和輪廓整合過程。

知覺學習：

知覺學習指通過訓練來提高感覺辨别能力的過程，被認為是在系統水平上發映了大腦的神經可塑性。近二十年來有大量的關于知覺學習的心理物理學，神經生理學，腦成像和計算神經科學的研究成果出現，是認知神經科學的一個重要研究領域。

我們的主要研究貢獻在于用創新性實驗範式，挑戰了視知覺學習研究關于視網膜位置特異性與朝向特異性的的基本假設以及基于這些假設的各種知覺學習理論 (Current Biology, 2008; J Neuroscience, 2010)。知覺學習因其位置與朝向特異性類似于視覺初級皮層(V1)的網膜拓撲對應特性和朝向選擇性，長期以來被認為反映了V1神經可塑性。但我們的研究證明知覺學習可以在不同網膜位置和朝向間完全遷移，位置與朝向特異性實際上是特定訓練方式的結果，而和知覺學習并無關系。這些發現還表明知覺學習是一個超出視覺皮層的高級認知過程。基于這些重要研究發現，我們初步提出了一個基于規則的知覺學習理論 (Rule-based perceptual learning theory) 來解釋知覺學習及其特異性與遷移的腦機制 (J Neuroscience, 2010)。目前我們進行的大量實驗皆在于驗證和發展這一理論，以及研究這一理論在臨床視覺訓練中的意義。

我們還發現對多個視覺刺激的知覺學習依賴于刺激的時間模式編碼, 當刺激的時間模式固定時才能獲得好的學習效應,而随機時間模式無法産生學習效果（Nature Neuroscience, 2005）。此外大腦學習多個刺激時，需要借助刺激的次序和節奏信息，或者刺激的概念或語義标簽，來幫助大腦識别各感覺刺激（PLoS Biology, 2008）。據此提出的刺激标簽模型 (Stimulus tagging model) 認為，大腦同時學習多個刺激時，需要在一定的時間窗口内通過刺激的固有次序和節奏, 或者在概念或語義水平上，對各刺激進行識别，從而幫助大腦将注意指向相應的神經過程，以在高級決策單元和各感覺刺激輸入之間建立相應的功能連接來實現知覺學習。

字符（漢字）識别：

我們發現筆劃數對漢字識别的大小阈限隻有有限的影響，而刺激間的幾何矩差能較好地模拟根據識别錯誤建立的混淆矩陣。這些結果證明漢字識别阈限主要受刺 激的總體特征所決定, 而較少受細節特征的影響（IOVS, 2007；Journal of Vision, 2009）。我們還對漢字識别在周邊視覺的表現及相關的視覺擁擠現象做了研究，發現了周邊視覺漢字識别存在着内部擁擠現象，以及top-down因素對視覺擁擠的影響（Vision Research, 2009）。最新的研究則發現，相當成分的視覺信息在視覺擁擠過程的影響下并沒有如當前理論所假設的喪失在識别過程中，而是在視覺記憶或注意過程中出現了錯位。這一發現為視覺擁擠現象提供了新的認識（Journal of Vision, 2012）。

輪廓整合：

我們在對周邊視覺輪廓整合的研究中, 發現在減少刺激不确定性後, 周邊視覺中的輪廓整合能力與中心視覺相當 (J Vision, 2006)。我們最近的研究興趣在輪廓整合的時間與空間特征 （VSS09, VSS10)。

英文論著

Zhao, X., Zhang, S., Tang, S., & Yu, C. (2025). Surround modulation is predominantly orientation-unspecific in macaque V1. Progress in Neurobiology, 247, 102745.

Xiao L, Liu L, Yu, C & Wu, S. (2024) A feature-task dual learning model of perceptual learning, 38th Conference on Neural Information Processing Systems (NeurIPS 2024).

Zhang, S. H., Zhao, X. N., Jiang, D. Q., Tang, S. M., & Yu, C. (2024). Ocular dominance-dependent binocular combination of monocular neuronal responses in macaque V1. ELife, 13, RP92839.

Zhao, X.-N., Guan, S.-C., Xiong, Y.-Z., & Yu, C. (2024). Crossmodal to unimodal transfer of temporal perceptual learning. Perception, 53(11-12), 753-762.

Zhao, X. N., Dong, X. S., Jiang, D. Q., Wu, S., Tang, S. M., & Yu, C. (2024). Population coding for figure-ground texture segregation in macaque V1 and V4. Progress in Neurobiology, 240, 102655.

Guan, S.-C., Xiong, Y.-Z., & Yu, C. (2024). Double training reveals an interval-invariant subsecond temporal structure in the brain. Journal of Experimental Psychology: Human Perception and Performance, 50(12), 1225–1235.

Zhang, S. H., Tang, S. M., & Yu, C. (2024). Testing Hubel and Wiesel’s “ice-cube” model of functional maps at cellular resolution in macaque V1. Cerebral Cortex, 34(12), bhae471.

Ju, N. S., Guan, S. C., Tang, S. M., & Yu, C. (2022). Macaque V1 responses to 2nd-order contrast-modulated stimuli and the possible subcortical and cortical contributions. Progress in Neurobiology, 102315.

Xiong, Y. Z., Guan, S. C., & Yu, C. (2022). A supramodal and conceptual representation of subsecond time revealed with perceptual learning of temporal interval discrimination. Scientific Reports, 12(1), 1-9.

Guan, S. C., Ju, N. S., Tao, L., Tang, S. M., & Yu, C. (2021) Functional organization of spatial frequency tuning in macaque V1 revealed with two-photon calcium imaging. Progress in Neurobiology, 205, 102120.

Hu, D. Z., Wen, K., Chen, L.H., & Yu, C. (2021) Perceptual learning evidence for supramodal representation of stimulus orientation at a conceptual level, Vision Research, 187, 120-128.

Ju, N. S., Guan, S. C., Tao, L., Tang, S. M., & Yu, C. (2021) Orientation tuning and end-stopping in macaque V1 studied with two-photon calcium imaging. Cerebral Cortex, 31, 2085-97.

Xie, X. Y., Zhao, X. N., & Yu, C. (2020). Perceptual learning of motion direction discrimination: Location specificity and the uncertain roles of dorsal and ventral areas. Vision Researh, 175, 51-57

Xie, X. Y., Liu, L. & Yu, C. (2020). A new perceptual training strategy to improve vision impaired by central vision loss. Vision Research, 174, 69-76.

Guan, S. C., Zhang, S. H., Zhang, Y. C., Tang, S. M., & Yu, C. (2020). Plaid detectors in macaque V1 revealed by two-photon imaging. Current Biology, 30, 934-940.

Xie, X. Y., & Yu, C. (2020). A new format of perceptual learning based on evidence abstraction from multiple stimuli, Journal of Vision, 20, 5.

Xiong, Y. Z., Tang, D. L., Zhang, Y. X., & Yu, C. (2020). Complete cross-frequency transfer of tone frequency learning after double training. Journal of Experimental Psychology: General, 149(1):94-103.

Xie, X. Y., & Yu, C. (2019). Perceptual learning of Vernier discrimination transfers from high to zero noise after double training. Vision Research, 156, 39-45.

Zhang, J.-Y., & Yu, C. (2018). Vernier learning with short- and long-staircase training and its transfer to a new location with double training. Journal of Vision, 18(13):8, 1–8.

Xie, X. Y. & Yu, C. (2018). Double training downshifts the threshold vs. noise contrast (TvC) functions. Vision Research, 152, 3-9.

Kuai, S. G., Li, W., Yu, C., & Kourtzi, Z. (2017). Contour integration over time: Psychophysical and fMRI evidence, Cerebral Cortex, 27, 3042-3051

Han, Q.M., Cong, L.J., Yu, C., & Liu, L. (2017). Developing a logarithmic Chinese reading acuity chart. Optometry and Vision Science, 94(6):714-724.

Xiong, Y.Z., Zhang, J.Y., & Yu, C. (2016). Bottom-up and top-down influences at untrained conditions determine perceptual learning specificity and transfer. eLife, 5:e14614.

Yin, C., Bi, Y.Q., Yu, C., & Wei, K.L. (2016). Eliminating direction specificity in visuomotor learning. Journal of Neuroscience, 36(13):3839-3847.

Wang, R., Wang, J., Zhang, J.Y., Xie, X.Y., Yang, Y.X., Luo, S.H., Yu, C., & Li, W. (2016). Perceptual learning at a conceptual level. Journal of Neuroscience, 36(7):2238-2246.

Zhang, J.Y., & Yu, C. (2016). The transfer of motion direction learning to an opposite direction enabled by double training: A reply to Liang et al. (2015). Journal of Vision, 16(3):29, 1-4.

Cong, L.J., Wang, R.J., Yu, C. & Zhang, J.Y. (2016). Perceptual learning of basic visual features remains task specific with Training-Plus-Exposure (TPE) training. Journal of Vision, 16(3):13, 1-9.

Xiong, Y. Z., Xie, X. Y., & Yu, C. (2016). Location and direction specificity in motion direction learning associated with a single-level method of constant stimuli. Vision Research, 119, 9–15.

Zhang, G.L., Li, H., Song, Y., & Yu, C. (2015). ERP C1 is top-down modulated by orientation perceptual learning. Journal of Vision, 15(10):8, 1-11.

Xiong, Y.Z., Yu, C., & Zhang, J.Y. (2015). Perceptual learning eases crowding by reducing recognition errors but not position errors. Journal of Vision, 15(11):16, 1-13.

Wang, R., Zhang J.Y., Klein, S. A., Levi, D. M. & Yu, C. (2014). Vernier perceptual learning transfers to completely untrained retinal locations after double training: a piggybacking effect. Journal of Vision, 14(13):12, 1-10.

Zhang, J.Y., Cong, L.J., Klein, S. A., Levi, D. M. & Yu, C. (2014). Perceptual learning improves adult amblyopic vision through rule-based cognitive compensation. Investigative Ophthalmology & Visual Science, 55, 2020-2030.

Wang, R., Cong, L.J., & Yu, C. (2013). The classical TDT perceptual learning is mostly temporal learning. Journal of Vision, 13(5):9, 1-9.

Zhang, G.L., Cong, L.J., Song, Y., & Yu, C. (2013). ERP P1-N1 changes associated with Vernier perceptual learning and its location specificity and transfer. Journal of Vision, 13(4):19, 1-13.

Wang, R., Zhang, J.Y., Klein, S. A., Levi, D. M. & Yu, C. (2012). Task relevancy and demand modulate double-training enabled transfer of perceptual learning. Vision Research, 61, 33-38.

Zhang, J.Y., Zhang, G.L., Liu, L., & Yu, C. (2012). Whole report uncovers correctly identified but incorrectly placed target information under visual crowding. Journal of Vision, 12(7):5, 1-11.

Liu, X. Y., Zhang, T., Jia, Y. L., Wang, N. L., & Yu, C. (2011). The therapeutic impact of perceptual learning on juvenile amblyopia with or without previous patching treatment. Investigative Ophthalmology & Visual Science, 52, 1531–1538.

Zhang, J.Y., Zhang, G.L., Xiao, L.Q., Klein, S. A., Levi, D. M. & Yu, C. (2010). Rule-based learning explains visual perceptual learning and its specificity and transfer. Journal of Neuroscience, 30, 12323-12328.

Zhang, T., Xiao, L. Q., Klein, S. A., Levi, D. M. & Yu, C. (2010). Decoupling location specificity from perceptual learning of orientation discrimination. Vision Research, 50, 368-374.

Liu, L., Klein, S.A., Xue, F., Zhang, J.Y., & Yu, C. (2009). Using geometric moments to explain human letter recognition near the acuity limit. Journal of Vision, 9(1):26, 1-18.

Zhang, J.Y., Zhang, T., Xue, F., Liu, L., & Yu, C. (2009). Legibility of Chinese characters in peripheral vision and the top-down influences on crowding. Vision Research, 49, 44-53.

Xiao, L. Q., Zhang, J.Y., Wang, R., Klein, S. A., Levi, D. M. & Yu, C. (2008). Complete transfer of perceptual learning across retinal locations enabled by double training. Current Biology, 18, 1922-1926.

Zhang, J.Y., Kuai, S.G., Xiao, L. Q., Klein, S. A., Levi, D. M. & Yu, C. (2008). Stimulus coding rules for perceptual learning. PLoS Biology, 6, 1651-1660.

Zhang, J.Y., Zhang, T., Xue, F., Liu, L., & Yu, C. (2007). Legibility of Chinese characters and its implications for visual acuity measurement in Chinese reading population. Investigative Ophthalmology & Visual Science, 48, 2383-2390.

Levi, D.M., Yu, C. , Kuai, S.G., & Rislove, E. (2007). Global contour processing in amblyopia. Vision Research, 47, 512-524.

Kuai, S.G. & Yu, C. (2006). Constant contour integration in peripheral vision for stimuli with good Gestalt properties. Journal of Vision, 6, 1412-20.

Kuai, S.G., Zhang, J.Y., Klein, S. A., Levi, D. M. & Yu, C. (2005). The essential role of stimulus temporal patterning in enabling perceptual learning. Nature Neuroscience, 8, 1497-1499.

Yu, C., Klein, S.A., & Levi, D.M. (2004). Perceptual learning in contrast discrimination and the (minimal) role of context. Journal of Vision, 4,169-182.

Yu, C. , Klein, S.A., & Levi, D.M. (2003). Cross- and iso- oriented surrounds modulate the contrast response function: The effect of surround contrast. Journal of Vision, 3，527-540.

Yu, C. , Klein, S.A., & Levi, D.M. (2002). Facilitation of contrast detection by cross-oriented surround stimuli and its psychophysical mechanisms. Journal of Vision, 2, 243-255.

Yu, C. , Klein, S.A., & Levi, D.M. (2001). Surround modulation of perceived contrast and the role of brightness induction. Journal of Vision, 1, 18-31.

Yu, C. & Levi, D.M. (2000). Surround modulation in human vision unmasked by masking experiments. Nature Neuroscience, 3, 724-728.

Yu, C. & Levi, D.M. (1999). The time course of psychophysical end-stopping. Vision Research, 39, 2063-2073.

Yu, C. & Levi, D.M. (1998). Rectification nonlinearity in cortical end-stopped perceptive field. Vision Research, 38, 3517-3530.

Yu, C. & Levi, D.M. (1998). Spatial frequency and orientation tuning in psychophysical end-stopping. Visual Neuroscience, 15, 585-595.

Yu, C. & Levi, D.M. (1998). Naso-temporal asymmetry of spatial interactions in strabismic amblyopia. Optometry and Vision Science, 75, 424-432.

Yu, C. & Levi, D.M. (1997). Spatial facilitation predicted with end-stopped spatial filters. Vision Research, 37, 3117-3127.

Yu, C. & Levi, D.M. (1997). Cortical components of the Westheimer function. Vision Research, 37, 2535-2544.

Yu, C. & Levi, D.M. (1997). End-stopping and length-tuning in psychophysical spatial filters. Journal of the Optical Society of America A, 14 , 2346-2354.

Yu, C. & Levi, D.M. (1997). Cortical end-stopped perceptive fields: Evidence from dichoptic and amblyopic studies. Vision Research, 37, 2261-2270.

Yu, C. & Essock, E.A. (1996). Spatial scaling of end-stopped perceptive fields: Differences in neural bases of end-zones, flanks, and centers. Vision Research, 36, 3129-3139.

Yu, C. & Essock, E.A. (1996). Psychophysical end-stopping associated with line target. Vision Research, 36, 2883-2896.