Decoded: How brain creates sequences
Posted on Jan 27 2014 | IANS
London, Jan 27 : Neuroscientists have discovered how the brain efficiently organises memories and actions by connecting separate small elements to become a unique and meaningful sequence.
"A specific area of the brain - the basal ganglia - is involved in a mechanism called chunking - that signals neurons to connect individual elements into a behavioural sequence, says a study published in the journal Nature Neuroscience.
"We trained mice to perform gradually faster sequences of lever presses - similar to a person who is learning to play a piano piece at an increasingly fast pace," explained Rui Costa from the Champalimaud Neuroscience Programme (CNP) in Lisbon, Portugal.
"By recording the neural activity in the basal ganglia during this task, we found neurons that seem to treat a whole sequence of actions as a single behaviour," he added.
The basal ganglia encompass two major pathways, the direct and the indirect.
The authors found that although activity in these pathways was similar during the initiation of movement, it was rather different during the execution of a behavioural sequence.
"The basal ganglia and these pathways are absolutely crucial for the execution of actions. These circuits are affected in neural disorders, such as Parkinson or Huntington's disease, in which learning of action sequences is impaired," added Xin Jin, an investigator at the Salk Institute in San Diego, US.
"We would further study the functional organisation of the basal ganglia during learning and execution of action sequences," Rui Costa said.