Sensorimotor learning and the ontogeny of the mirror neuron system

Hebbian learning and predictive mirror neurons for actions, sensations and emotions

“…For instance, each time a person gives something to baby, the sight of the placing hand will just precede the execution of grasping and could lead to some degree of association between STS neurons for placing and PM neurons for grasping. Indeed, so-called 'logically related mirror neurons' seem to exist [2], and laboratory experiments suggest that repeatedly experiencing non-matching contingencies can temporarily link motor programmes to non-matching action observations (see section 4 of [39] for a review). Additionally, an object that can be grasped in a particular way will always be systematically present when baby grasps that object in that way, predicting Hebbian connections between shape neurons in the visual system and PM neurons that code the affordances of this object.…”

Associative (not Hebbian) learning and the mirror neuron system

“…[1]) and Hebbian [20] accounts of the development of the MNS. 2 Full details of all model parameters are given in the supplementary materials. The complete model, which is written in the C programming language, is available for download from http://www.ccnl.bbk.ac.uk/models.html 3 Thus, if w ij (t) is the weight of the association to node j from node i at time t, then for each learning trial w ij (t+1) = w ij (t) + λ.∆w ji 4 The one parameter that was not held at its value from previous work was the habituation threshold of sensory nodes.…”

“…Catmur [2] has reviewed the evidence that sensorimotor experience makes a distinctive contribution to the development of the MNS. Behavioural, electrophysiological and neuroimaging studies with adult humans have shown that, when the potential contributions of sensory experience and motor experience are controlled, a relatively brief period of novel sensorimotor experience can change MNS responsivity in a variety of ways.…”

The role of handedness-dependent sensorimotor experience in the development of mirroring

“…The process for imitating actions requires us to map an observed action onto a motor program used to perform that action. This mapping process could be mediated by the human mirror system, a neural network of brain regions that directly matches observed actions onto the observer's motor programs [1][2][3][4]. The mirror system is considered to match observed-effector actions onto the identical and similar motor programs to be performed [5][6][7].…”

“…Recently, it is argued that the mirror system is forged by domaingeneral processes of associative learning in the course of individual development, and not an innate endowment [10,11]. Supporting this view, a number of studies suggested that the property of matching observed actions with motor programs (mirror property) is not fixed, but is rather flexibly modified through sensorimotor associative experience [3,4,[12][13][14][15]. For example, after the training of performing one action while observing another action, the mirror system begins to match this observed action onto the motor program of the simultaneously performed action [13].…”