Benedetto A., Arrighi R., Castaldi E. Commun Biol (2026). https://doi.org/10.1038/s42003-026-10746-3 https://www.nature.com/articles/s42003-026-10746-3#citeas Numerosity perception enables us to quickly estimate the number of objects in a visual scene, a fundamental skill supporting efficient interaction with the environment. In this study, we tracked how the human brain transforms physical inputs into numerical percepts. Using EEG, we characterized the temporal dynamics of h

Burgio I., Maldonado Moscoso P.A., Anobile G., Castaldi E. BMC Biol. 2025 Oct 14;23(1):305. doi: 10.1186/s12915-025-02417-2. PMID: 41088111; PMCID: PMC12522993. https://pmc.ncbi.nlm.nih.gov/articles/PMC12522993/ Background: 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. T

Karami A., Castaldi E., Eger E., Piazza M. Commun Biol. 2025 Jul 9;8(1):1029. doi: 10.1038/s42003-025-08395-z. PMID: 40634477; PMCID: PMC12241354. https://pmc.ncbi.nlm.nih.gov/articles/PMC12241354/ Visual numerosity, traditionally linked to the parietal cortex, is now thought to be represented across a broader cortical network, including early visual and associative areas in both streams. However, how numerosity is encoded relative to other visual features remains unclear. We

Castellotti S., Castaldi E., Blini E., Arrighi R. Acta Psychol (Amst). 2025 Mar;253:104720. doi: 10.1016/j.actpsy.2025.104720. Epub 2025 Jan 11. PMID: 39799929. https://www.sciencedirect.com/science/article/pii/S0001691825000332?via%3Dihub The objective assessment of cognitive processes is of critical importance to understanding the mechanisms underlying various mental functions and dysfunctions. In recent years, the technological innovations related to the eye-tracking indus

Caponi C., Castaldi E., Grasso P.A., Arrighi R. Proc Biol Sci. 2025 Jan;292(2039):20241841. doi: 10.1098/rspb.2024.1841. Epub 2025 Jan 29. PMID: 39876730; PMCID: PMC11775598. https://pmc.ncbi.nlm.nih.gov/articles/PMC11775598/ Perceptual adaptation has been widely used to infer the existence of numerosity detectors, enabling animals to quickly estimate the number of objects in a scene. Here, we investigated, in humans, whether numerosity adaptation is influenced by stimulus fe

Maldonado Moscoso PA, Anobile G, Maduli G, Arrighi R, Castaldi E. Open Mind (Camb). 2025 Jan 20;9:121-137. doi: 10.1162/opmi_a_00181. PMID: 39877146; PMCID: PMC11774540. https://pmc.ncbi.nlm.nih.gov/articles/PMC11774540/ When objects are grouped in space, humans can estimate numerosity more precisely than when they are randomly scattered. This phenomenon, called groupitizing, is thought to arise from the interplay of two components: the subitizing system which identifies both

Castaldi E., Tinelli F., Filippo G., Bartoli M., Anobile G. Res Dev Disabil. 2024 Jun;149:104733. doi: 10.1016/j.ridd.2024.104733. Epub 2024 Apr 25. PMID: 38663331; PMCID: PMC11155440. https://pmc.ncbi.nlm.nih.gov/articles/PMC11155440/ Developmental dyscalculia (DD) is a specific learning disability which prevents children from acquiring adequate numerical and arithmetical competences. We investigated whether difficulties in children with DD spread beyond the numerical domain

Caponi C., Castaldi E., Burr D.C., Binda P. Sci Rep. 2024 Mar 13;14(1):6097. doi: 10.1038/s41598-024-55646-w. PMID: 38480839; PMCID: PMC10938002. https://pmc.ncbi.nlm.nih.gov/articles/PMC10938002/ We recently showed that the gain of the pupillary light response depends on numerosity, with weaker responses to fewer items. Here we show that this effect holds when the stimuli are physically identical but are perceived as less numerous due to numerosity adaptation. Twenty-eight p

Castaldi E., Bonaudo C., Maduli G., Anobile G., Pedone A., Capelli F., Arrighi R., Della Puppa A. Brain Sci. 2024 Jan 10;14(1):69. doi: 10.3390/brainsci14010069. PMID: 38248284; PMCID: PMC10813954. https://www.mdpi.com/2076-3425/14/1/69 A precise neuropsychological assessment is of the utmost importance for neurosurgical patients undergoing the surgical excision of cerebral lesions. The assessment of mathematical abilities is usually limited to arithmetical operations while o