Dear Students!
Our last speaker for this semester on the 11th of April will be Detlef Heck who will talk
about: "Conducting the neuronal symphony: The special role of the cerebellum in cognitive function".
You
will need to read the papers titled:"The Cerebellum and Cognitive Function: 25 Years of Insight from Anatomy and Neuroimaging"
Please post your comments not later than Tuesday (10th) afternoon!
During the last 25 years, there has been a great deal of change in the view of the cerebellum and its role in cognition. These changes were the result of advances in neuroimaging techniques. Buckner (2013) reviews two of the major anatomical works that led to better understanding of the cerebellum. Previous research assumed that motor areas of the brain were the primary target for the cerebellum; however, these studies showed that the cerebellum does send and receive information from non-motor areas of the brain. I found the discussion of the potential selection pressures for increased cerebellum size interesting. The paper raises the question as to whether the selection pressure is directly on increasing the size of the cerebellum or if the increased size is simply a result of an overall increase in brain size. Buckner seems to lean toward the overall increase in brain size as part of the explanation but is it also possible that there is a selection pressure directly on the cerebellum as well? The cerebal cortex scales at the largest rate of growth as overall brain size increases and the cerebellum scales at a rate second to this. What does this all really mean from an evolutionary standpoint? Is it that as cognitive functioning increased in a common ancestor the cerebellum became utilized by more than just sensory-motor function?
ReplyDeleteBuckner presents an overview of recent research that shows that the cerebellum plays an important role in cognitive function and is not just involved in sensorimotor functioning. This evidence comes from imaging studies that show distinct patterns of cerebellar activity in response to increased cognitive load that is not attributable to known motor areas. Furthermore, recent advances in anatomical techniques have shown that major areas of the cerebellar cortex are topographically connected to pre-frontal areas in the cerebral cortex.
ReplyDeleteQuestions:
* I have a personal interest in sensorimotor integration and self-monitoring during speech production. Given the role of the cerebellum in sensorimotor integration and coordination of skilled movements (e.g. speech) and its connection to pre-frontal areas associated with executive functioning and planning (important for self-monitoring), have there been any cerebellum specific studies that have looked at continuous performance self-monitoring and speech errors under varying degrees of cognitive load?
* What are some the most common behavioral paradigms used to measure cognitive function of the cerebellum?
Research within the last 25 years has shifted from focusing on the cerebellum as serving a role strictly in the planning and execution of motor movements to incorporating its interconnectedness to association areas with the cortex and its role in higher cognitive function. More recent neuroimaging techniques have revealed activations within distinct cerebellar regions (different than those activated during motor tasks) during cognitive tasks suggesting that the cerebellum is involved in both feedforward and feedback loops to the prefrontal areas. Further study has revealed that the functional asymmetry of the cortex appears to be preserved in contralateral cerebellar representations. Furthermore, these findings have led to the hypothesis that disruptions within the cerebellar and cerebral network may lead to neuropsychiatric conditions.
ReplyDeleteThe article notes that there is a lack of representation of visual and auditory cortex in the cerebellum. What might this suggest about these sensory systems?
The cerebellum was originally thought to be used for motor-related functions only. The discovery of a polysynaptic circuitry has led researchers to believe that the cerebellum plays a larger role in more higher cognition systems, including the prefrontal cortex, supported by the discovery that the association cortex is larger in humans relative to apes and other species. It is believed that the cerebellum’s feedback loop for regulating the motor system may be similarly organized in its connection to the association cortex for the regulation of higher cognitive functions. In the same way that one can over or undershoot a motor plan, it is then possible to conceive of the relevance to psychiatric disorders as a disorder in cerebellar function relating to the disequilibrium of thought processes.
ReplyDeleteQuestion: How strong of a connection is the motor/prefrontal cortex circuitry that leads from the cerebellum? Could an intervention that works to habilitate one connection potentially also improve the other? For example, if a client is working on a therapy to improve ataxic movements, could this generalize to an improvement in disrupted higher cognitive functioning, and vice versa?
Until recently, the cerebellum was believed to primarily be involved in the planning and execution of movements. However, the last 25 years have seen a radical shift in this view where the cerebellum has been associated with several cerebral networks involved in cognition. This article reviews evidence that the cerebellum responds to cognitive task demands, likely related to projections with the prefrontal cortex and cerebral association regions. Consistent with the idea of cerebellar involvement of motor planning and execution, body maps in the cerebellum mirror what is observed in the cortex, including preservation of functional asymmetries. Despite these links between cognitive functions and the cerebellum, cerebellar lesions do not typically produce marked cognitive deficits. Future research will hopefully clarify this apparent discrepancy in the literature.
ReplyDeleteJessica Yoo
ReplyDeleteThe cerebellum and cognitive function: 25 years of insight from anatomy and neuroimaging (Buckner, 2013)
The article discusses the role of the cerebellum and how the views of it have been changed since the past years. Through the neuroimaging studies with monkeys (Schmahmann and Strick), Buckner shows that cerebellum is involved in cognitive regions integrating incoming information rather than strictly sensory-motor areas. Moreover, cerebellum may be studied for its role in mental processes like in neuropsychiatric disease. Schmahmann believes that because cerebellum control factors such as the rate and accuracy of motor behaviors, it may also influence similar factors in mental disorders. Buckner offers a thought on evolution of brain structures such as the increased cerebellum size in humans and apes. What may have been the factors that drove this “direct selection”?
This paper is a general review about the research and discovery about the cerebellum and its role in our human brain. The development of the technology greatly improve the method of scientists to study the cerebellum. The understanding of the cerebellum is improved from only motor function to cognition and process. It is a good review to have a general map about the study of cerebllum. I don't have many comments.
ReplyDeleteIn page 812, Jeremy Schahmann pointed out that cerebellum may play a role in mental illness. Can we have some examples about this statement? I would like to know is there anything thing related to mental disorder like autism.