By utilizing brain scanning, cognitive neuroscientists can:
History of Cognitive NeuroscienceCognitive neuroscience is an interdisciplinary area of study that has emerged from neuroscience and psychology. There were several stages in these disciplines that changed the way researchers approached their investigations and that led to the field becoming fully established. Show Although the task of it is to describe how the brain creates the mind, historically it has progressed by investigating how a certain area of the brain supports a given mental faculty. The phrenologist movement failed to supply a scientific basis for its theories and has since been rejected. The aggregate field view, meaning all areas of the brain participated in all behavior, was also rejected as a result of brain mapping. Perhaps the first serious attempt to localize mental functions to specific areas in the human brain was by Broca and Wernicke. This was mostly achieved by studying the effects of injuries on different parts of the brain on psychological functions. These studies formed the basis for neuropsychology, one of the central areas of research, which began to establish links between behavior and its neural substrates. Brain mapping began with Hitzig and Fritsch’s experiments published in 1870. These studies formed the research that was further developed through methods such as positron emission tomography (PET) and functional magnetic resonance imaging (fMRI). The Nobel Prize of 1906 recognized Golgi and Cajal’s essential work on the neuron doctrine. Several findings in the 20th century continued to advance the field. Findings like the discovery of ocular dominance columns, recording of single nerve cells in animals, and coordination of eye and head movements were major contributions. Experimental psychology was significant in the foundation of cognitive neuroscience. Findings include the demonstration that some tasks are accomplished via discrete processing stages, the study of attention, and the notion that behavioral data do not provide enough information by themselves to explain mental processes. As a result, some experimental psychologists began to investigate the neural bases of behavior. A 1967 book named Cognitive Psychology by Ulric Neisser reported the discussion of a 1956 meeting at the Massachusetts Institute of Technology, where George A. Miller, Noam Chomsky, and Newell & Simon presented important papers. Around this time, the term “psychology” was falling out of fashion, and researchers were more likely to refer to “cognitive science.” The term cognitive neuroscience itself was coined by Michael Gazzaniga and cognitive psychologist George Armitage Miller, interestingly, while sharing a taxi in 1976. Cognitive neuroscience began to integrate the newly-laid theoretical ground in cognitive science, that emerged between the 1950s and 1960s, with approaches in experimental psychology, neuropsychology, and neuroscience. Neuroscience was formally recognized as a unified discipline in 1971. In the 20th century, new technologies evolved that are now the mainstay of the methodology of cognitive neuroscience, including EEG (human EEG 1920), MEG (1968), TMS (1985) and fMRI (1991). Recently the focus of research has expanded from the localization of brain area(s) for specific functions in the adult brain using a single technology. Studies explore the interactions between different brain areas, using multiple technologies and approaches to understand brain functions, and using computational approaches. Advances in non-invasive functional neuroimaging and associated data analysis methods have made it possible to use highly naturalistic stimuli and tasks in cognitive neuroscience studies.
Researchers shouldn’t fear papers that test and find flaws in methods. Such work contributes to better experimental designs and better science.
Some types of brain-imaging study need sample sizes in the thousands to reach reliable conclusions on how variations in brain structure affect behaviour.Credit: Mark Harmel/Alamy In 2008, Craig Bennett put a dead salmon in an magnetic resonance imaging (MRI) scanner. Bennett, a postgraduate psychology student at the University of California, Santa Barbara, then studied how the fish’s brain lit up in ‘response’ to photographs of humans in different emotional states1. That this experiment discerned any brain activity at all — it was intended purely as an exercise to calibrate the scanner — served as an early warning sign that care should be taken in interpreting the statistical significance of findings from brain-imaging experiments. Fast forward to today, and some think the field of cognitive neuroscience has a full-blown reproducibility problem. Conversely, others think that the salmon study, along with subsequent work identifying methodological weaknesses, has moved the field forwards, inspiring researchers to make better decisions about experimental design and data interpretation.  Read the paper: Reproducible brain-wide association studies require thousands of individuals In March, Nature published a paper2 by Scott Marek at Washington University School of Medicine in St. Louis, Missouri, and his colleagues that investigated the reproducibility of brain-wide association studies. Such studies use neuroimaging techniques to explore how variations in brain structure or function affect behaviour, cognition or mental health. Marek et al. found that sample sizes in the thousands are needed to reliably characterize such relationships, although the authors note that they did not investigate all possible techniques or populations. The paper prompted some soul-searching that will hopefully move the field towards more robust work. Predictive puzzlesThis week, Abigail Greene at Yale University School of Medicine in New Haven, Connecticut, and her colleagues tackle the reliability of predictive modelling in cognitive neuroscience3. The method, which is used widely in the biological sciences, uses existing data sets to forecast future outcomes. It has been applied to cognitive neuroscience in an effort to determine the relationship between patterns of brain activity and various cognitive and behavioural traits. Unlike brain-wide association studies, predictive-modelling studies can be reliable with smaller sample sizes. Read the paper: Brain–phenotype models fail for individuals who defy sample stereotypes Greene and her co-workers systematically characterized the cases for which predictive models fail to generate accurate predictions in cognitive neuroscience, and show that this failure is not random. Rather, it tends to occur for certain groups of people regardless of the data set — groups that aren’t average. This might be interpreted as showing that, in cognitive neuroscience, predictive models lack methodological robustness, fuelling wider concerns about the field. Some researchers have told Nature that, since the publication of Marek and colleagues’ work, reviewers of papers and grants have had a more negative view of neuroimaging studies with small sample sizes — even if they are not brain-wide association studies. The implication is that grants need to get larger, involving consortia that can collect data from thousands, which could crowd out small research groups and researchers in low-resource settings. Others fear that the findings will contribute to a perception among scientists outside the field that cognitive neuroscience is statistically underpowered and based on models that systematically fail. However, these studies provide the opportunity for significant growth in the field, as they have done in others. Can brain scans reveal behaviour? Bombshell study says not yet Around 20 years ago, the genetics community needed to confront the reality that studies looking to determine the genetic basis of traits using candidate-gene approaches were not producing results that said meaningful things about genes and diseases. Genetics was much more complex than they had originally realized and, among other things, needed greater statistical firepower. Researchers turned to genome-wide association studies, which scan the genomes of many people in an effort to determine whether and how variations are associated with particular diseases, such as heart disease or cancer. One of the earliest such studies, of 96 people with age-related macular degeneration — a major cause of blindness in older people — and 50 control participants, revealed more about the hereditary nature of the condition4. Studies involving much larger numbers of people soon followed, and researchers have since confirmed that larger sample sizes are better for reproducibility5. As a result, genetics has been transformed. It is both more robust and more collaborative, with statisticians working alongside life scientists. The field of cognitive neuroscience has been experiencing a growth spurt similar to the one genetics went through two decades ago. Growth requires a lot of energy and can be painful, but it is an integral part of life and evolution. The findings of Greene et al. and Marek et al. should not be seen as a criticism of the field or its methods, nor be interpreted as evidence of a reproducibility crisis. By presenting clear analyses to guide researchers in choosing their experimental designs and interpreting their results when using two important methods, they provide the sort of self-reflection necessary to move cognitive neuroscience to the next level. For a discipline to progress, we must not only appreciate its strengths, but also understand its weaknesses. References
Download references What techniques does cognitive neuroscience use?EEG (ERP), MEG (ERF), fMRI, and PET are the 4 techniques currently most used to record neural data in humans.
What is the impact of neuroscience on cognitive psychology?Neuroscience studies the brain's structure and what areas get activated when an individual does certain tasks. Cognitive psychology looks at behaviour. Changes in the brain may or may not impact behaviour. Neuroscience at best is helping to confirm what cognitive psychology has produced in behaviour.
Why is cognitive neuroscience useful?Cognitive neuroscience deepens the understanding of the nature of scientific knowledge. Cognitive neuroscience contributes to the solution of problems found in contemporary philosophy of science.
What does a cognitive neuroscientist study quizlet?The study of the relationships between neuroscience and cognitive psychology, especially those theories of the mind dealing with memory, sensation and perception, problem solving, language processing, motor functions, and cognition.
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