Undergraduate Honors Theses

Thesis Defended

Spring 2016

Document Type


Type of Thesis

Departmental Honors



First Advisor

Dr. Yuko Munakata

Second Advisor

Dr. Sabine Doebel


The use of private speech (PS), non-social speech that is audible or internalized, is important for engaging in the successful use of executive functions (EFs). EFs are general mechanisms that allow us to control and regulate our behaviors, thoughts and feelings. A developmental transition has been posited in private speech during early childhood, changing from overt to more covert with age; this transition might support developmental improvements in EFs. However, previous research has focused on a limited set of tasks, has not tested whether overt private speech might decrease with age due to other factors (e.g., talkativeness), and has not tested how private speech relates to real-world EF. The current study investigated the developmental transition in private speech in a cross-sectional sample of 30 children between the ages of 5 and 7 years old. The use of four cognitive tasks allowed a test of the generalizability of developmental changes in private speech. Correlations were found across a few tasks but not across the entire battery, which may suggest that children utilize different levels of PS based on task demands. Two covariate measures (talkativeness and extroversion) allowed a test of whether other factors may play a role in overt private speech. Extroversion was significantly positively correlated with some tasks, and negatively correlated with age, which suggests that developmental decreases in overt speech may be driven by developmental decreases in extroversion. Real-world EF was assessed via a parent questionnaire, the Behavior Rating Inventory of Executive Function (BRIEF). Use of PS on some tasks was trending with BRIEF scores, which suggests that PS may play a role in real world EF.