Charles Fernyhough is a writer and psychologist at Durham University. He directs Hearing the Voice (hearingthevoice.org), a project on voice-hearing and inner speech funded by the Wellcome Trust.
In his study, conducted in 2011 at Durham University, UK, Dr. Fernyhough and his colleague Simon McCarthy-Jones found that 60 per cent of people report that their inner speech has the same quality of a conversation. Inner speech has some very special properties. Much of modern research has been inspired by the long-neglected theories of L. S. Vygotsky, a Russian psychologist whose career unfolded in the early days of the Soviet Union.
Starting with observations of children talking to themselves while playing, Vygotsky hypothesised that this “private speech” develops out of social dialogue with parents and caregivers. Over time, these private mutterings become further internalised to form inner speech.
Vygotsky proposed that inner speech undergoes some important transformations as it becomes internalised, such as becoming abbreviated or condensed relative to external speech. For instance, when hearing a loud metallic sound outside at night and realising that the cat is to blame, you probably wouldn’t say to yourself, “The cat has knocked the dustbin over.” Instead, you might just say, “The cat,” since that utterance contains all the information you need to express to yourself.
Because it develops from social interactions, self talk takes on some of the qualities of a dialogue, an exchange between different points of view.
Vygotsky’s theory also suggests some possibilities about the way inner speech is created in the brain. If it is derived from external speech, as he proposed, both might be expected to activate the same neural networks.
One of Vygotsky’s most important finding was that private and inner speech give us a way of taking control of our own behaviour, by using words to direct our actions. While driving up to a roundabout in busy traffic, for example says Dr. Fernyhough, I’ll still tell myself, “Give way to the right”.
Therefore, improving our inner speech means improving our behaviour.
Inner speech can foster our personal growth when used to make plans and improve self awareness.
People with autism, meanwhile, who often have problems with linguistic communication, seem not to use inner speech for planning, although they do use it for other purposes such as short-term memory. A more dramatic difficulty comes from damage to the language areas of the brain, which can silence some people’s inner voices. One such individual, neuroanatomist Jill Bolte Taylor, reported a lack of self-awareness after a stroke that damaged her language system – supporting the view that verbal thinking may be important for self-understanding and self control.
Adapted by Life in the chatter box, New Scientist, June 2013