AQA Psychology for A Level Year 2: Rev Guide

@ookx hs @ookx hs Michael Schumacher won the world Formula One racing championship seven times. In 2013 he suffered a serious head injury during a skiing accident. He was in a medically-induced coma for several months. Schumacher’s condition slowly improved and he showed some signs of recovery. He began to learn to walk and speak again, but continued to have memory problems. Using Michael Schumacher’s experience as an example, explain what psychologists have discovered about plasticity of the brain and its functional recovery after trauma. Chapter 2: Biopsychology Spec spotlight Plasticity and functional recovery of the brain after trauma. The brain is plastic, not rubber. Plasticity and functional recovery of the brain AO1 Description On these AO1 pages, there are nearly always six key points for each topic. This easily covers the descriptive content you would need for any essay – because description is worth 6 marks. Don’t be tempted to over-describe. Revision booster Brain plasticity The brain is ‘plastic’ – synaptic connections form and are pruned. During infancy, the brain experiences a rapid growth in synaptic connections, peaking at about 15,000 at age 2–3 years (Gopnick et al. 1999). As we age, rarely used connections are deleted and frequently used connections are strengthened – synaptic pruning . It was once thought these changes were limited to childhood. But recent research suggests neural connections can change or be formed at any time, due to learning and experience. The concept of plasticity is supported by studies. Maguire et al . (2000) found significantly more volume of grey matter in the posterior hippocampus in London taxi drivers than in a matched control group . This part of the brain is linked with the development of spatial and navigational skills. As part of their training, London cabbies take a complex test called ‘The Knowledge’ to assess their recall of city streets and possible routes. This learning experience appears to alter the structure of the taxi drivers’ brains! The longer they had been in the job, the more pronounced was the structural difference. Plasticity is also supported by other research. Draganski et al . (2006) imaged the brains of medical students three months before and after final exams. Learning-induced changes were seen in the posterior hippocampus and the parietal cortex, presumably as a result of the exam. Functional recovery of the brain after trauma Following trauma unaffected areas of the brain take over lost functions . Functional recovery of the brain after trauma is an important example of neural plasticity – healthy brain areas take over functions of areas damaged, destroyed or even missing. Neuroscientists suggest this process occurs quickly after trauma (spontaneous recovery) and then slows down – at which point the person may require rehabilitative therapy. The brain ‘rewires’ itself by forming new synaptic connections. The brain is able to rewire and reorganise itself by forming new synaptic connections close to the area of damage. Secondary neural pathways that would not typically be used to carry out certain functions are activated or ‘unmasked’ to enable functioning to continue. Structural changes in the brain (e.g. axonal sprouting ). Further structural changes may include: • Axonal sprouting – growth of new nerve endings which connect with other undamaged cells to form new neuronal pathways. • Reformation of blood vessels . • Recruitment of homologous (similar) areas on the opposite side of the brain to perform specific tasks. 32