Private speech and the development of verbal self-regulation

In a series of studies begun when I was a doctoral student at Cambridge, I have tested neoVygotskian hypotheses about the development of verbal mediation of cognition and behaviour. In one study (Fernyhough & Russell, 1997), we found evidence that children's private speech plays a role in their establishment of themselves as thinking agents. Another study (Fernyhough & Fradley, 2005) tested hypotheses about the relations among self-regulatory private speech, task difficulty and task performance, adding to the body of research that suggests that private speech can enhance children's cognition. In a cross-cultural study conducted in Saudi Arabia and the UK (Al-Namlah et al., 2006), we examined links between children's self-regulatory private speech and their use of phonological recoding on short-term memory tasks, concluding that private speech may be involved in an across-the-board shift to verbal mediation in the early school years. With my colleagues Adam Winsler and Nacho Montero I have edited a book for CUP on the topic of private speech. My graduate student Jane Lidstone has recently employed a dual-task paradigm to investigate the role of private speech in planning in middle childhood (Lidstone et al., 2010).

Inner speech and dialogic thinking

I am interested in one specific implication of Vygotsky's ideas about private and inner speech: namely, that thinking has a dialogic quality. In my first publication in this area (Fernyhough, 1996), I set out some of the implications of a dialogic approach to the higher mental functions for the development of executive functioning and theory of mind. I have since developed these ideas in BBS commentaries on Carpendale and Lewis (2004) and Tomasello et al. (2005). A full statement of this position appeared in Developmental Review in 2008.

Auditory-verbal hallucinations

With my colleague Simon McCarthy-Jones, I have applied my model of inner speech and dialogic thinking to the study of auditory verbal hallucinations (Fernyhough, 2004; Jones & Fernyhough, 2007). In collaboration with colleagues in Bangor and Manchester, I have been developing theoretical developmental models of specific symptoms such as delusions and hallucinations (e.g., Bentall et al., 2007). My main collaborator in this respect is Richard Bentall. A theoretical statement on this topic recently appeared in Schizophrenia Bulletin. I have been investigating cognitive correlates of hallucination-like experiences in clinical and non-clinical samples, such as occur in the hypnagogic and hypnopompic states. In studies conducted in collaboration with colleagues from MACCS (Sydney, Australia), we have been investigating hallucination-like experiences in schoolage children (Fernyhough et al., 2007), as well as assessing typical inner speech in patients with schizophrenia.

I am leading an interdisciplinary project on voice-hearing, Hearing the Voice, centred at Durham University.

I am involved in a consortium of researchers studying predictors of depression in the ALSPAC sample.

Mind-mindedness

With my colleague Elizabeth Meins I have been studying individual differences in parental mind-mindedness and their implications for children's development. Our aim in developing this construct has been to rethink maternal sensitivity in line with Mary Ainsworth's original conception (Meins et al., 2001). We were the first group to establish a longitudinal connection between security of attachment in infancy and children's later mentalising abilities (Fernyhough et al., 1995; Meins et al., 1998). To date we have published findings from two separate longitudinal studies linking maternal mind-mindedness to children's mentalising development (Meins et al., 1998; Meins & Fernyhough, 1999; Meins et al., 2002; 2003). In both samples we have found that mind-mindedness accounts for the observed relation between attachment security and children's later theory of mind performance. We have also found that maternal mind-mindedness at 6 months predicts security of attachment at 12 months more strongly than typical measures of maternal sensitivity (Meins et al., 2001). Recently we have begun to study individual differences in mind-mindedness in children, finding that such differences are unrelated to children's mentalising abilities (Meins et al., 2006). Coupled with findings of temporal stability in mothers' mind-mindedness (Meins et al., 1998; 2003), this suggests that mind-mindedness is a trait-like measure of individuals' motivation to deploy their mentalising abilities, rather than a measure of those abilities themselves (Meins et al., 2006).

I am involved in the ESRC-funded Tees Valley Baby Study, a longitudinal study based in Stockton-on-Tees, in which we are examining developmental relations among a range of variables including child and adult attachment behaviours, mind-mindedness, and internal working models. In recent outputs from this study, we have investigated the origins of individual differences in mind-mindedness, and relations with joint attention in infancy.

Other research topics

In addition to the above-mentioned research topics, I have published research into imaginary companions, specific language impairment, autism, childhood anxiety, delusions, attachment and schizotypy, stress in psychosis, working memory, and literary models of mind.