With two other authors (one from the University of Birmingham's Computer Science school), Jeannette Littlemore and Almut Koester have recently published a study that measured the extent of students’ awareness of their metaphor interpretation difficulties, plus a scheme for categorizing the most common types of metaphor misinterpretations. 

The error categorization scheme could be used in helping English learners with metaphor comprehension as well as helping metaphor researchers to explore the psychological processes underlying metaphor comprehension.