Data for: Multimodal convergence in the pedunculopontine tegmental nucleus: motor, sensory, and theta-frequency inputs influence the activity of single neurons

The pedunculopontine tegmental nucleus of the brainstem (PPTg) has
extensive interconnections and neuronal-behavioural correlates. It is
implicated in movement control and sensorimotor integration. We
investigated whether single neuron activity in freely moving rats is
correlated with components of skilled forelimb movement and whether
individual neurons respond to both motor and sensory events. We found that
individual PPTg neurons showed changes in firing rate at different times
during the reach. This type of temporally specific modulation is like
activity seen elsewhere in voluntary movement control circuits, such as
the motor cortex, and suggests that PPTg neural activity is related to
different specific events occurring during the reach. In particular, many
neuronal modulations were time-locked to the end of the extension phase of
the reach, when fine distal movements related to food grasping occur,
indicating strong engagement of PPTg in this phase of skilled individual
forelimb movements. In addition, some neurons showed brief periods of
apparent oscillatory firing in the theta range at specific phases of the
reach-to-grasp movement. When movement-related neurons were tested with
tone stimuli, many also responded to this auditory input, allowing for
sensorimotor integration at the cellular level. Together, these data
extend the concept of the PPTg as an integrative structure in the
generation of complex movements, by showing that this function extends to
the highly coordinated control of the forelimb during skilled reach to
grasp movement and that sensory and motor-related information converges on
a single neuron, allowing for direct integration at the cellular level.