6 research outputs found
The self-organization of combinatoriality and phonotactics in vocalization systems
This paper shows how a society of agents can self-organize a shared vocalization system that is
discrete, combinatorial and has a form of primitive phonotactics, starting from holistic inarticulate
vocalizations. The originality of the system is that: (1) it does not include any explicit pressure for
communication; (2) agents do not possess capabilities of coordinated interactions, in particular they
do not play language games; (3) agents possess no specific linguistic capacities; and (4) initially
there exists no convention that agents can use. As a consequence, the system shows how a primitive
speech code may bootstrap in the absence of a communication system between agents, i.e. before the
appearance of language
Discovering Communication
What kind of motivation drives child language development? This
article presents a computational model and a robotic experiment to articulate
the hypothesis that children discover communication as a result
of exploring and playing with their environment. The considered
robotic agent is intrinsically motivated towards situations in which
it optimally progresses in learning. To experience optimal learning
progress, it must avoid situations already familiar but also situations
where nothing can be learnt. The robot is placed in an environment in
which both communicating and non-communicating objects are present.
As a consequence of its intrinsic motivation, the robot explores this environment
in an organized manner focusing first on non-communicative
activities and then discovering the learning potential of certain types of
interactive behaviour. In this experiment, the agent ends up being interested
by communication through vocal interactions without having
a specific drive for communication
Nicotinic receptors in the ventral tegmental area promote uncertainty-seeking.
International audienceCholinergic neurotransmission affects decision-making, notably through the modulation of perceptual processing in the cortex. In addition, acetylcholine acts on value-based decisions through as yet unknown mechanisms. We found that nicotinic acetylcholine receptors (nAChRs) expressed in the ventral tegmental area (VTA) are involved in the translation of expected uncertainty into motivational value. We developed a multi-armed bandit task for mice with three locations, each associated with a different reward probability. We found that mice lacking the nAChR β2 subunit showed less uncertainty-seeking than their wild-type counterparts. Using model-based analysis, we found that reward uncertainty motivated wild-type mice, but not mice lacking the nAChR β2 subunit. Selective re-expression of the β2 subunit in the VTA was sufficient to restore spontaneous bursting activity in dopamine neurons and uncertainty-seeking. Our results reveal an unanticipated role for subcortical nAChRs in motivation induced by expected uncertainty and provide a parsimonious account for a wealth of behaviors related to nAChRs in the VTA expressing the β2 subunit
Towards a neuroscience of active sampling and curiosity
International audienc