Tadashi Koyama. Current research on individual differences in early expressive word acquisition. Journal of Special Education Research,. 2021. 11. 1. 11-21
Koyama Tadashi. Relationship between Children's Play, Cognitive Development at Home, and Early Language Learning. The Japan Journal of Logopedics and Phoniatrics. 2020. 61. 4. 342-350
Koyama Tadashi. Cognition through Interaction with Objects and Language Development in Children with Intellectual Developmental Disorders. The Japan Journal of Logopedics and Phoniatrics. 2020. 61. 2. 177-187
Koyama Tadashi. Development of Imitation in the Child with Autism : A case study of the child with severe speech delay. Faculty bulletin humanities and science. 2006. 26. 113-118
Sakakibara Hiroko, Koyama Tadashi. Early Language Acquisition and Development of Play in the Children with Autistic Spectrum. Annual report of the Faculty of Education, Gifu University. Humanities and social sciences. 2004. 52. 2. 423-437
Fundamental development for the emergence of pointing in children with general learning difficulties.
(British Psychological Society, Developmental Section Annual Conference 2021 2021)
Children’s daily play at their home and early language development.
(2019)
Early gestures, actions on objects, and language comprehension in the children with developmental disorders: Precursors to language.
(48th Annual Meeting of the Jean Piaget Society, Poster Session 1, 19, Amsterdam, Netherland . 2018)