The Cambridge Handbook of Communication Disorders examines the full range of developmental and acquired communication disorders and provides the most up-to-date and comprehensive guide to the epidemiology, aetiology and clinical features of these disorders.
AUTHOR: Blakemore, Sarah-Jayne and Uta Frith TITLE: The Learning Brain. Lessons for Education YEAR: 2005. PUBLISHER: Blackwell Publishing Dr. Alona Soschen, Department of Linguistics and Philosophy and the Department of Brain and Cognitive Sciences, MIT. ''The Learning Brain'' is written by two leading authorities in the field. Sarah-Jayne Blakemore is engaged in neuroscience research, for which she obtained the 2001 British Psychological Society Award. Uta Frith is the author of well-known books on autism and Asperger syndrome. The present work provides a detailed account of how our brain learns during the whole of development including adulthood, and discusses the implications of this knowledge for educational policy and practice. It aims to demonstrate, with examples, how brain research on learning at different ages could influence and improve our understanding of teaching. Cognitive psychology is viewed as tailor-made for the role of a mediator between brain science and education. 1. Introduction In the introduction, the authors discuss the importance of interactions between brain scientists and educators, nature and nurture factors, misconceptions about neuroscience, genetics, disorders of the developing brain, and the brain's aging. In addition, basic information on neuronal organization is provided, accompanied by illustrations. Modern techniques used to study the brain are addressed in a concise form; a more detailed overview of these techniques can be found in the Appendix at the back of the book. 2. The Developing Brain What changes in the brain during development? Is it too late for change after the age of three? The authors contend that synaptogenesis is considerably longer. The process of adding myelin to axons - which acts as an insulator speeding up movement of impulses down the neuron - continues well into teens and twenties. Synaptogenesis may be linked to the initial emergence of some skills and capacities, but their refinement continues after synaptic densities are cut back through pruning (1). The chapter addresses the important question of whether knowledge about the world arises from formal education, or develops better without any explicit teaching, through exploration and communication. Would children develop better mathematical, language, and musical abilities through intensive instruction such as 'hot-housing'? Aren't these important abilities based mostly on everyday experiences such as social interaction and sharing? The discussion focuses on several closely related issues, such as sensitive periods in learning and the importance of enriched environments. 3. Words and Numbers in Early Childhood This part concentrates on the development of language and arithmetic skills in children. The authors provide examples of experimental work showing that abstract rules for learning a natural language are innate, while language-specific parameters are not. In the process of learning, some features such as certain phonological differences either become more prominent or lose their significance, depending on the language being acquired (2)(3). The authors address a foreign accent problem, babbling in babies, fast-mapping and dyspraxia (difficulties in motor coordination), and raise the question whether infants can be taught to write before the age of five, given the under-developed fine finger coordination at that age. Another important issue under consideration in Chapter 3 is whether very young children have a concept of number. 4. The Mathematical Brain The parietal lobe involved in spatial orientation is also associated with mathematical abilities. Calculation abilities depend on the hemisphere responsible for different components of mathematics. The focus of this part is on the studies of patients with brain damage and dyscalculia (4). As a continuation of the discussion of mathematical abilities, the authors introduce two controversial topics: the left brain/right brain theory, and gender differences in the brain. 5. The Literate Brain Brain research has shown that literacy has an effect on spoken language processing. Chapter 5 concentrates on the experiments that demonstrate differences between literate and illiterate brains and expose the brain's reading system. Interestingly, the differences in the weighting of certain regions of the reading system in different languages show that more work is done either by the region responsible for whole word recognition (English) or by the region responsible for letter-sound translation (Italian). 6. Learning to Read and its Difficulties The studies showed that even in the youngest readers, reading induced neural activity in left hemisphere areas and a switch of activity from right to left: activity declined in right hemisphere areas during the same time period. The development of reading skills, reading impairments such as dyslexia, teaching dyslexic people to read, and the effects of remedial teaching are the main focus of the experimental work under discussion. The studies suggest that dyslexics can boost integration of the sight and sound of words by recruiting their right parietal lobe, in contrast with unimpaired readers who are automatically given this integration through the specialized areas of the reading system in the left hemisphere. 7. Disorders of Social-Emotional Development The authors look at developmental disorders that affect social and emotional experience, in particular the attention deficit hyperactivity disorder ADHD, conduct, empathy and moral sensitivity disorders, Asperger syndrome, and autism. A question that needs to be answered is whether it is the existence of different modules in the brain that accounts for the unusual talents in autism, showing that in this case, only some but not all brain systems are disrupted. Is it possible that instead of some kind of pre-programming inherent in the brain, experience itself will lead to the gradual development of modules in adults (5)? Theories of developmental disorders may have effects on remedial teaching and help find the ways to overcome problems such as mind blindness – the ability to relate to other minds - in autism. 8. The Adolescent Brain The brain undergoes a second wave of development during adolescence. How does puberty affect it? As neurons develop, the transmission speed gets faster, and vigorous synaptic pruning occurs after puberty in the frontal lobes. The researchers concluded that a decrease in synaptic density and a simultaneous increase in axonal myelination are evidenced by the loss of gray matter and constant increase in white matter. In behavior, social awareness seems to show a massive change: fear might become rewarding, and peer pressure can start to determine actions. Decision making and the ability to carry out multiple tasks at once are abilities that might improve during adolescence; however, the studies show that there is a dip of performance on tasks that require decision making. The frontal cortex develops in a nonlinear fashion; the teen frontal lobes undergo a phase of waxing and waning. 9. Life Long Learning Recent research has revealed that the adult brain is able to change in size and activity, thus allowing it to continue learning. Plasticity occurs as a compensatory mechanism in people who have lost some function. The visual cortex takes over the job of processing tactile information in blind people who read Braille, which attests to the adaptive capacity of the brain. Adult brains can grow new cells: the important implication is that exercise boosts both learning and brain development, releasing the hidden powers of the human mind. 10. Learning and Remembering Neuroscience is beginning to understand the brain mechanisms underlying learning. The aim of this part is to reveal the nature of learning itself, which can be achieved by studying the neural structures involved in learning and memory processes. This research will answer the questions of how learning can be enhanced, and how we can learn without even being aware of it. In this chapter, the authors discuss learning and remembering skills, different types of memory and its disorders. We know hardly anything about what goes on in the brain when we teach; the authors view theory of mind as a prerequisite for purposeful teaching. 11. Different Ways of Learning The older one gets, the harder rote learning – i.e. by repeating words over and over – seems to become. Brain science provides further evidence for other effective methods of learning, such as visual and emotional imagery. It was discovered that certain neurons in the premotor cortex of a monkey's brain 'fire' when the monkey observes someone grasping an object. Interestingly, it is a goal directed action performed by a hand that grasps the object that interests those cells, not the object itself. Imitation is important for learning: inhibition occurs gradually, allowing children to imitate more, thus learning more. Experimental psychology has long established that mental exercise is important for learning various skills: it can be exploited in training of physical skills such as sport and dancing. Cognitive therapy that retrains people in the way they think about a particular issue is often successful in treating problems such as phobias, obsessive-compulsive behavior, and anorexia. 12. Harnessing the Learning Powers of the Brain In the final chapter, the authors speculate about how various lines of research are shedding light on biological and sociological aspects of learning. This part provides a discussion of sleep, hypnosis, emotion, reward, risk taking, and nutrients that change the brain processes. For example, the brain, although fast asleep, is still taking in salient information. Sleep deprivation has detrimental effects on memory, while sufficient sleep facilitates insight. Hypnosis may increase productivity in some individuals, while emotionally charged events are always remembered better than neutral events. Certain substances and foods are especially beneficial for mental ability. Last but not least, the effect of social and other rewards cannot be underestimated (6). In their conclusion, the authors stress the importance of interdisciplinary approaches to the study of learning mechanisms, a new science of learning that draws from neurophysiology, psychology, and education (7). The book also provides an Appendix, Glossary, References, Further Reading Suggestions, and an Index. EVALUATION I enjoyed reading this highly informative book, written in a way that makes it accessible not only to specialists but to anyone interested in the study of learning. The range of experimental work is particularly impressive. Many of the experiments described are most interesting as they are the ones that have not yet been widely reported. The chapters are well-organized and accompanied by illustrations, many of which will make you smile. Humor is definitely a powerful tool in bringing a point across. I recommend this book to educators and others who wish to know more about memory, learning, and cognition. In this review, I have provided a brief summary of chapters, followed by endnotes and references. In the endnotes, I offer some observations and suggestions as to how the investigation of learning mechanisms could be further developed and incorporated within the interdisciplinary field that studies the human mind from a broader perspective. ENDNOTES 1) Gallistel's The Organization of Learning challenges commonly held beliefs about memory as consisting of changes in the synaptic connections between neurons, and contends that the only plausible elementary mechanisms common to learning in general are the ones involved in the storing of the computed values of variables and carrying out computation. This process is worthy of intensive study at the neurobiological level and it ought to be of interest to scientists who seek to discover the mechanisms that make learning and higher cognitive function possible. Furthermore, Gallistel suggests that the concept of a gradual learning curve is inaccurate. Learning is more than the strengthening of associative bonds between synapses - the reason why the rate of learning can vary greatly from one subject to the next. 2) In the development of visual perception, children born with cataracts after eye surgery could distinguish between different faces but failed to distinguish the ones that differed only in the arrangement of their features (discussed on pp. 28-29). It shows that a human cognitive system treats the significance of space as a parameter that has to be set during a certain period of time. The example of children born with visual defects can be regarded as parallel to certain cases of individuals with language impairments. Those patients have their vocabulary intact but their syntax - the dynamic part of language responsible for the organization of lexical items – is deficient. 3) See Kenneth Wexler's important work on the development of language in children, syntax in particular. 4) The observation that patients with an impaired system of calculation (summation, subtraction) still preserve the ability to estimate quantities confirms the idea that basic mental representations are continuous rather than discrete. Gallistel et al. (to appear) arrive at a conclusion that 'the non-verbal system for arithmetic reasoning with mental magnitudes precedes the verbal system both phylogenetically and ontogenetically...The special role of the natural numbers in the cultural history of arithmetic is a consequence of the discrete character of human language, which picks out of the system of real numbers in the brain the discretely ordered subset generated by the nonverbal counting process, and makes these the foundation of the linguistically mediated conception of number.' 5) Cognitive dissociations in autism may be caused by either limited growth or excessive pruning of long-range connections early in development (Brock et al. 2002). It is possible that excessive brain size in autism is linked to the development of extra short-range connections as a compensatory mechanism. 6) Certain ways of provoking enthusiasm in learners can be close to manipulation, as in advertising and politics (p.184). Establishing which context is healthy and which is not should be one of the priorities in teaching. Importantly, education exceeds school boundaries by far. While teaching science to children is beneficial, the media's focus on promoting consumer goods without any reference to the role of science and research involved in their production is not. Education in any form should be enriching; this goal is a challenge to all educators and the consumer-oriented society itself. 7) How can we use our brain power more effectively? (p. 187). Theoretical studies of the human mind such as biolinguistics, a science that sees language as a part of a more general system, cannot be underestimated. If Hauser et al. are right and the only species-specific part of human language is recursion, then finding out more about syntax - a unique type of recursive system - might reveal the principled organization in the brain. This research will lead to a better understanding of how our mind works and eventually show ways to optimize learning and improve the development of the brain. REFERENCES Brock, J., Brown, C. C., Boucher, J., & Rippon, G. (2002). The temporal binding deficit hypothesis of autism. Development and Psychopathology, 14, 209-224. Gallistel, C.R. 1990. The organization of learning. Cambridge, MA: MIT Press. Gallistel, C.R., Gelman, R., and S. Cordes (to appear). The cultural and evolutionary history of the real numbers. S. Levinson and P. Jaisson (eds). Culture and evolution. Cambridge, MA: MIT Press. Hauser, Marc D., Chomsky, N., and W. T. Fitch. 2002. The Faculty of Language: What Is It, Who Has It, and How Did It Evolve? Science 22 November 2002: Vol. 298. No. 5598, 1569 – 1579.
ABOUT THE REVIEWER:
ABOUT THE REVIEWER
Dr. Alona Soschen is a scholar at the Department of Linguistics and Philosophy and the Department of Brain and Cognitive Sciences, MIT, a leading center for research on formal models of human language and the interrelations between linguistics, psychology, philosophy, and mathematics. Her interests include syntactic theories, comparative syntax (not limited to Slavic, Germanic, Romance, Semitic language groups), language acquisition, mathematical modeling of language, and modern studies of cognition. Her present work focuses on the Chomskyan Minimalist Program, while developing a biolinguistic approach to the core syntactic units and combining it with analyses implemented by means of formal logic. Her recent article "Natural Law: The dynamics of Syntactic Representations in MP" investigates the principles of argument structure and syntactic phase formation as a part of a more general model present in all biological systems of efficient growth, in an attempt to establish the criteria that single out these particular species-specific components of the Faculty of Language. The article can be found at http://www.ling.uni-potsdam.de/lip/