In the first lecture, we reviewed the various hypotheses that have been proposed about the cognitive functions that form the core of the language faculty. Starting with the systematic but already long-standing proposals of linguist James Hockett, and the more recent ideas of the key article by Mark Hauser, Noam Chomsky and W. Tecumseh Fitch (2002), we have retained two essential hypotheses:
- firstly, that the human brain possesses a singular capacity to forge a " system of symbolic links ", arbitrary, bidirectional, linking signifiers and signifieds (in Saussurean terminology);
- secondly, the human brain is equipped with one or more " Combinatorics systems ", enabling it to compose these symbols to produce an infinite number of expressions capable of evoking an infinite number of meanings.
These two hypotheses place the human singularity at a high cognitive level: the ability to manipulate and combine symbols. In this first lecture, we also discussed another, lower-level, sensory-motor hypothesis, according to which the language faculty of the human species has its origins in the anatomy and biomechanics of the vocal apparatus. Recent research suggests that changes in the anatomy of the larynx may not play as essential a role as previously thought, since two studies indicate that the vocal apparatus of macaques and baboons is already capable of producing many phonemes. On the other hand, in the brain circuits controlling the vocal apparatus, we can clearly see adaptations specific to Homo sapiens : the existence of a specific laryngeal motor cortex and direct axonal projections to motor neurons in the brainstem.
