Learning to tie the knot: The acquisition of functional object representations by physical and observational experience.

Here we examined neural substrates for physically and observationally learning to construct novel objects, and characterized brain regions associated with each kind of learning using fMRI. Each participant was assigned a training partner, and for five consecutive days practiced tying one group of knots ("tied" condition) or watched their partner tie different knots ("watched" condition) while a third set of knots remained untrained. Functional MRI was obtained prior to and immediately following the week of training while participants performed a visual knot-matching task.

Physical experience leads to enhanced object perception in parietal cortex: insights from knot tying.

What does it mean to "know" what an object is? Viewing objects from different categories (e.g., tools vs.

Chunking and compound cueing of movement sequences: learning, retention, and transfer.

When teaching a complex sequence, the sequence is often chunked into components; however, this strategy may not always benefit learning, but may be detrimental. The hypothesis is that this occurs because chunking deprives learners of compound cues that could aid recall. To test this, participants learned 9-item movement sequences, either as three 3-item chunks or as one 9-item series.

Sex differences in the acquisition of complex skilled movements.

The praxis system comprises a network of brain regions dedicated to complex skilled movements. Following suggestions of a female advantage on learned movements (Chipman and Hampson in Neuropsychologia 44(12):2315-2329, 2006), we investigated how males and females acquire skilled movements. Subjects viewed and imitated sequences of hand movements, which were repeated ten times.

Transient disruption of M1 during response planning impairs subsequent offline consolidation.

Transcranial magnetic stimulation (TMS) was used to probe the involvement of the left primary motor cortex (M1) in the consolidation of a sequencing skill. In particular we asked: (1) if M1 is involved in consolidation of planning processes prior to response execution (2) whether movement preparation and movement execution can undergo consolidation independently and (3) whether sequence consolidation can occur in a stimulus specific manner. TMS was applied to left M1 while subjects prepared left hand sequential finger responses for three different movement sequences, presented in an interleaved fashion.

Ventral and dorsal stream contributions to the online control of immediate and delayed grasping: a TMS approach.

According to Milner and Goodale's theory of the two visual streams, the dorsal (action) stream controls actions in real-time, whereas the ventral (perceptual) stream stores longer-term information for object identification. By this account, the dorsal stream subserves actions carried out immediately. However, when a delay is required before the response, the ventral (perceptual) stream is recruited.