Background <p>Perception is inferential, relying not only on current sensory input but also on prior knowledge. When sensory input is unreliable, history effects such as central tendency and serial dependence smooth out noise by combining previous and current stimuli. These processes support perceptual continuity but also introduce biases, making the current stimulus appear erroneously similar to the previous one. Despite being observed in many perceptual domains, the mechanisms underlying these dynamic processes remain debated. Although perceptual, cognitive, and developmental factors have been studied, the influence of psychological traits has received little attention. In this study, we compared serial dependence and central tendency effects measured with a visual numerosity task across individuals with different levels of math anxiety.</p> Results <p>We found that individuals with higher math anxiety exhibited worse numerosity thresholds as well as stronger central tendency and serial dependence effects compared to those with lower math anxiety. Both effects were best explained by differences in participants’ sensory thresholds and were unrelated to their visuo-spatial working memory, suggesting they mainly originate from perceptual uncertainty rather than memory span. Math anxiety, as measured by a questionnaire, demonstrated minimal predictive power in explaining history effects once sensory precision was accounted for. Finally, we found no correlation between serial dependence and central tendency effects, suggesting that they may rely on independent mechanisms.</p> Conclusions <p>Overall, our study indicates that central tendency and serial dependence are distinct perceptual mechanisms, both amplified in individuals with reduced sensory precision linked to specific psychological traits, such as math anxiety.</p>