AQA Psychology for A Level Year 2 - Student Bk

1. Define what is meant by plasticity in the brain. [3 marks] 2. Briefly outline research into functional recovery of the brain after injury. [5 marks] 3. Discuss research into plasticity of the brain including functional recovery. [16 marks] Check It Methods: The case of Gabby Giffords Gabby Giffords is a former US Democratic politician who survived an assassination attempt in 2011 when she was shot in the head from point blank range. Doctors placed Giffords into a waking coma such was the critical nature of her condition. Within months, however, she had made staggering progress. With the aid of physical rehabilitation, Giffords was able to walk under supervision with perfect control of her left arm and leg, and able to write with her left hand. She could read, understand and speak in short phrases. Doctors suggested that Giffords’ progress would place her in the top 5% of people recovering from serious brain injury – a remarkable example of the brain’s ability to heal itself. Question With reference to the example of Gabby Giffords above, briefly discuss strengths and limitations of the case study approach. ( 6 marks ) @ookx hs @ookx hs Support from animal studies Early evidence of neuroplasticity and functional recovery was derived from animal studies. A pioneering study by David Hubel and Torten Wiesel (1963) involved sewing one eye of a kitten shut and analysing the brain’s cortical responses. It was found that the area of the visual cortex associated with the shut eye was not idle (as had been predicted) but continued to process information from the open eye. Consider: Early studies such as this paved the way for modern research into neuroplasticity and functional recovery. Does what we learn from early studies such as these justify the procedures that were used which caused permanent damage to the animals? Conduct a cost-benefits analysis and decide. The concept of cognitive reserve Evidence suggests that a person’s educational attainment may influence how well the brain functionally adapts after injury. Eric Schneider et al . (2014) discovered that the more time brain injury patients had spent in education – which was taken as an indication of their ‘cognitive reserve’ – the greater their chances of a disability-free recovery (DFR). Two-fifths of patients studied who achieved DFR had more than 16 years’ education compared to about 10% of patients who had less than 12 years’ education. Consider: What other factors may influence how well a person recovers from a brain injury? Evaluation e X tra Evaluation Practical application Understanding the processes involved in plasticity has contributed to the field of neurorehabilitation . Following illness or injury to the brain, spontaneous recovery tends to slow down after a number of weeks so forms of physical therapy may be required to maintain improvements in functioning. Techniques may include movement therapy and electrical stimulation of the brain to counter the deficits in motor and/or cognitive functioning that may be experienced following a stroke, for instance. This shows that, although the brain may have the capacity to ‘fix itself’ to a point, this process requires further intervention if it is to be completely successful. Negative plasticity The brain’s ability to rewire itself can sometimes have maladaptive behavioural consequences. Prolonged drug use, for instance, has been shown to result in poorer cognitive functioning as well as an increased risk of dementia later in life (Medina et al . 2007). Also, 60–80% of amputees have been known to develop phantom limb syndrome – the continued experience of sensations in the missing limb as if it were still there. These sensations are usually unpleasant, painful and are thought to be due to cortical reorganisation in the somatosensory cortex that occurs as a result of limb loss (Ramachandran and Hirstein 1998). Age and plasticity Functional plasticity tends to reduce with age. The brain has a greater propensity for reorganisation in childhood as it is constantly adapting to new experiences and learning. That said, Ladina Bezzola et al . (2012) demonstrated how 40 hours of golf training produced changes in the neural representation of movement in participants aged 40–60. Using fMRI , the researchers observed reduced motor cortex activity in the novice golfers compared to a control group , suggesting more efficient neural representations after training. This shows that neural plasticity does continue throughout the lifespan. Concepts: Meditation and mindfulness A number of recent neuroscientific studies have examined the effects of prolonged periods of meditation on the brain. Some of these studies have more specifically explored the concept of mindfulness – an ancient Buddhist practice defined as ‘an intentional and non-judgemental focus on one’s own emotions, thoughts and sensations occurring in the present moment’ (www.anniegurton.com , 2015). As well being linked to reduced everyday tension and stress, meditation and mindfulness may alter the structure and function of the brain. Lazar et al . (2005), using MRI scans , demonstrated how experienced meditators had a thicker cortex than non-meditators, particularly in areas related to attention and sensory processing. Individuals who took part in an 8-week Mindfulness-Based Stress Reduction course showed an increase in grey matter in the left hippocampus, a part of the brain strongly associated with learning and memory (Holzel et al. 2011). Finally, Tang et al. (2012) found that four weeks of meditation resulted in an increase in white matter in the anterior cingulate cortex , a part of the brain that contributes to self- regulation and control (a key aspect of meditational practice). Question Can you think of examples of other everyday behaviours that could alter the structure and/or function of the brain? @ookx hs plasticity and functional recovery of the brain after trauma 41 •