PSYCHOLOGY - Draganski study

Method

The participants were 21 females and 3 males between the ages of 20 and 24. All participants were non jugglers and they had an MRI scan at the start of the study to serve as a base rate for grey matter and brain structure.

Participants were allocated to one of two conditions - jugglers and non-jugglers. Those in the juggling category were taught a routine and asked to practice it and notify the researchers when they had mastered it.

They then did a second MRI scan and were told not to juggle anymore. A third scan was then carried out three months later.

The non-juggling group served as a control.

This study can be used for

Neuroplasticity - neural pruning, (techniques, and localisation of function)

Carried out by

Draganski et al. 2006

Research method

Experiment

Independent variable

The amount of juggling they learnt

Dependent variable

The amount of grey matter/density of dendritic branches

Aim

To see whether learning a new skill, juggling, would have an effect on the brains of the participants.

Results

The jugglers showed a significant increase in gray matter and neural density in the mid-temporal area in both hemispheres - a place associated with visual memory.

In the third scan, after many were no longer able to carry out the juggling routine, the amount of grey matter had decreased.

There was no change in te non-juggling sample.

Evaluation

The study used a pre-test, post-test design to show differences in neural density over time.

It was experimental, thus helping argue for a cause and effect relationship

There was a control group

The sample size was very small - so it is possible that by using averages of growth, the data may not be reliable.

There are possible problems of internal validity as participants were in their home environments for most of the study.

Neural pruning

Neural pruning is an aspect of neuroplasticity in which unnecessary neurones are eliminated.

There is regulatory pruning that occurs in the early stages if life, between childhood and the mid-twenties, and there is pruning in the matured brain. This pruning follows the "use it or lose it" principle. Frequently used synapses have strong Connections while rarely used synapses have weak connections and are therefore eliminated.

Mental illness that start to emerge in adolescence E.g schizophrenia may be as a result of abnormal neural pruning.

Advantages of neural pruning

It ensures that the neural networks are effective and functional by getting rid of unnecessary cells.

Neurones compete for resources and so it is important that only those that are necessary survive, hence why after the jugglers stoped practicing the neurones were pounced as they were deemed unnecessary due to lack of repetition of the activity.