Personality
A number of personality characteristics have been proposed as likely to affect second language learning, but it has not been easy to demonstrate their effects in empirical studies. As with other research investigating the effects of individual characteristics on second language learning, different studies measuring a similar personality trait produce different results. For example, it is often argued that an extroverted person is well-suited to language learning. However, research does not always support this conclusion. Although some studies have found that success in language learning is highly related to learners' scores on some characteristics often associated with extroversion such as assertiveness and adventurousness, others have found that successful language learners do not get high scores on measures of extroversion.

Another aspect of personality which has been studied is inhibition. It has been suggested that inhibition discourages risk-taking which is necessary for progress in language learning. This is often considered to be a particular problem for adolescents, who are more self conscious than younger learners. In a series of studies, Alexander Guiora and his colleagues have found support for the claim that inhibition is a negative force in language learning. One study involved an analysis of the effects of small doses of alcohol on pronunciation (Guiora et al.1972). It was found that subjects who received small doses of alcohol did better on pronunciation tests than those who did not drink any alcohol. While results such as these are interesting, as well as amusing, they are not convincing, since experiments such as these are far removed from the reality of the classroom situation. We may also note, in passing, that when larger doses of alcohol were administered, pronunciation rapidly deteriorated!

Several other personality characteristics such as self esteem, empathy, dominance, talkativeness, and responsiveness, have also been studied. However, in general, the available research does not show a clearly defined relationship between personality and second language acquisition. And, as indicated earlier, the major difficulty in investigating personality characteristics is that of identification and measurement. Another explanation which has been offered for the mixed findings of personality studies is that personality variables may be a major factor only in the acquisition of communicative competence. The confused picture of the research on personality factors is due in part to the fact that comparisons are made between studies that measure communicative ability and studies that measure grammatical accuracy or knowledge of linguistic rules. Personality variables seem to be consistently related to the former, but not to the latter. Despite the inconclusive results and the problems involved in carrying out research in the area of personality characteristics, many researchers believe that personality will be shown to have an important influence on success in language learning. This relationship is a complex one, however, in that it is probably not personality alone, but the way in which it combines with other factors that contributes to second language learning.