Recent modeling work shows that patterns of shared perceptual features relate to the group-level order of acquisition of early-learned words (Peters & Borovsky, 2019). Here we present results for two eye-tracked word recognition studies showing patterns of shared perceptual features likewise influence processing of known and novel noun-concepts in individual 24- to 30-monthold toddlers. In the first study (Chapter 2, N=54), we explored the influence of perceptual connectivity on both initial attentional biases to known objects and subsequent label processing. In the second study (Chapter 3, N=49), we investigated whether perceptual connectivity influences patterns of attention during learning opportunities for novel object-features and object-labels, subsequent pre-labeling attentional biases, and object-label learning outcomes. Results across studies revealed four main findings. First, patterns of shared (visual-motion and visual-form and surface) perceptual features do relate to differences in early noun-concept processing at the individual level. Second, such influences are tentatively at play from the outset of novel noun-concept learning. Third, connectivity driven attentional biases to both recently learned and well-known objects follow a similar timecourse and show similar patterns of individual differences. Fourth, initial, pre-labeling attentional biases to objects relate to subsequent label processing, but do not linearly explain effects of connectivity. Finally, we consider whether these findings provide support for shared-feature-guided selective attention to object features as a mechanism underlying early lexico-semantic development. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]