For each of us the first vocal communication is the (infant’s) cry. With this spontaneous gesture the infant powerfully enters the world of human communicational interaction. From an evolutionary perspective the central behavioural patterns that distinguish mammals from other animals are 1) maternal / parental care of the newborn; 2) the “separation” call; and 3) play. In humans these developments are highly developed and reflected in human brain development. Human brain development provides a complex interface with the environment. It is clear that each of these patterns as well as language itself can only emerge in an interpersonal context. An intersubjective understanding of evolution recognizes not just the “call” of the infant (self) but also the “response” of the other as necessary to any notion of selective advantage for the species.
Language as it is spoken and heard cannot be separated from affective vocalization although these two dimensions of speech are subserved by different neural networks. From the perspective of psychotherapy the interpersonal / affective dimension of language has a particular resonance and salience. While humans may share some basic emotional responses with other mammals, crying as a complex emotional expression is thought to be unique to humans. Cultural attitudes to this and other emotional forms of expression have a profound influence on expressive behaviours. Language, as one of the central carriers of culture, also reciprocally modifies both affective vocal expression and the understanding of emotional life. The development of language in humans depends on an enculturation process that is affectively and relationally motivated. The human neo-cortex is a necessary but not sufficient condition for this development. Both language and human evolution need to be understood as having an intersubjective basis to be “meaningful”.