draganski et al (2004)

Neural pruning

• Neural pruning is the process by which extra neurons and synaptic connections are eliminated to increase the efficiency of neuronal transmissions, occurring when the synaptic connections aren’t used.

• It typically occurs during childhood and adolescence but can continue into adulthood, shaping brain plasticity based on experience.

• Neural pruning is influenced by factors such as environmental demands, learning, and synaptic activity, meaning that frequently used connections are strengthened while unused connections are removed.

Aim

Find out whether the human brain can change structure in response to environmental demands

Procedure

Random sampling design, self-selected sample

Randomly allocated a sample of volunteers into 2 groups

One : jugglers

Two : non-jugglers

Made sure that both groups had no experience of juggling before the start of the experiment

First MRI performed

Participants in the juggler group subsequently spent three months learning a classic juggling routine with three balls

Second MRI performed

Participants in the juggler group spent three months where they were instructed not to practice juggling

Third MRI performed

Results

Prior to the start of the experiment there was no difference in brain structure

Second scan the juggler had more gray matter in some areas of the cortex mostly the mid-temporal area

Third scan differences decreased but jugglers denser gray matter

Conclusion

If we practice something then our brain will increase and when we stop practicing then it will decrease again, but often not to its original state

Strengths

No researcher bias - random sampling

Replicable

Cause/Effect relationship

Limitations

Low ecological validity

Participant bias - self-selected