Dance+&+the+Brain

Dance & the Brain


 * INTRODUCTION **

Dance is an art form that requires the coordination of the entire body. More specifically, as described by two authors for the Scientific American Magazine, it is “a confluence of movement, rhythm, and gestural representations” that require complex mental coordination (Brown et al. 2008). Many people enjoy dance for its aesthetic appeal, but studies have implicated significant findings not just for passive observors of dance, such as audience members who don't hold any intention to learn what is being performed, or active observors who are being shown the example of movememnt so that they can later mimic it, but for the actual dancer themself. Whether amateur or professional, there is a lot occurring on the neurological level which explains how the integration of clues from the environment are translated into actual executed movements.

Neuroscientists had paid little to no consideration to dance, until relatively recently when they realized how significant the connection betweem the two were. Thus they began to conduct some of the first brain-imaging studies looking at the neural basis of dance.

 Through this scanner, neuroscientists were able to further investigate what specific brain structures are involved in different aspects.
 * Positron Emission Tomography [|(PET)] **

While there are localized areas of the brain that are activated when performing sensorimotor activities, there is also an overlap in neural activity, which demonstrates the integration of the individual aspects of dance such as spatial pattern, rhythm, synchronization to external stimuli, and ultimately whole-body coordination. This can be read in further detail in the section below: **the integration of brain areas to allow for dance. **

The figure to the left is an illustration of a subject demonstrating the dance task whilelying suping in the PET scanner. Prior to the scan, subjects were trained to perform simple bipedal dance movements. This was to limit the occurrence of any motor learning during the time that scans were taken.


 * ANATOMY AND FUNCTION OF BRAIN STRUCTURES INVOLVED IN DANCE **

The scans revealed activations in many regions of the brain contributing to dance learning and performance. Knowing the location and function of these specific brain structures and regions will provide helpful in understanding the unique role that they play both individually, and as a system.


 * Motor cortex, specifically the primary motor cortex (M1), the premotor cortex (PMA), and the supplementary cortex (SMA)
 * Somatosensory cortex
 * Basal ganglia
 * <span style="font-family: Georgia,serif;">Cerebellum, with a focus on the v<span style="font-family: Georgia,serif;">ermis, lobules IV and VIII, and lobule III
 * <span style="font-family: Georgia,serif;">Parietal lobule
 * <span style="font-family: Georgia,serif;">Right frontal operculum – involved in motor sequencing
 * <span style="font-family: Georgia,serif;">Cingulate motor area (right) – processes aspects of movement intention, and allocation of motor resources

<span style="font-family: Georgia,serif;">The motor cortex is a part of of the cerebral cortex that is invovled in many different aspects of voluntary motor functions including the planning, control, and execution of voluntary movement. It is composed of four different parts. The **primary motor cortex (M1)** is located in the posterior aspect of the frontal lobe. Its role is to control the simple features of movement, which it does with the help of Betz cells, large neurons located in grey matter of M1. These neurons descend to the spinal cord and ultimately have direct synapses with their target muscles. The **premotor cortex (PMA)** rests in the frontal lobe, and received inputs from motor nuclei in the ventro -anterior and -lateral thalamus, the primary somatosensory cortex, along with the prefrontal association cortex. Neurons located in the PMA, which include mirror neurons, are activated during the preparation of movement. In addition, the premotor cortex has roles in the control of both proximal muscles and trunk muscles. The **posterior parietal cortex** is located has a role in the production of planned movements, as it produces motor commands from the visual, auditory, and somatosensory input that it receives from those systems. The last section of the motor cortex is the **supplementary motor area (SMA)**, which is located in front of the primary motor cortex. Its responsibilities are in motor action planning and coordination for complex movements, including movement arising from interal sources, such as memory.
 * <span style="font-family: Georgia,serif;">Motor Cortex **

<span style="font-family: Georgia,serif;">The somatosensory cortex is located in the postcentral gyrus of the parietal lobe. As this region is the primary sensory receptive area for touch, it is responsible for motor control, and eye-hand coordination related to tactile information from touch and experience through memory. Also located in this area is the sensory homunculus.
 * <span style="font-family: Georgia,serif;">Somatosensory Cortex **

<span style="font-family: Georgia,serif;">The basal ganglia are composed of a group of four nuclei which all play a role in voluntary movement. While they don<span style="font-family: Georgia,serif;"> 't have direct inputs or projections with the spinal cord, they receive their input from the cerebral cortex and send their output through the thalamus to the brainstem, as well as to the prefrontal, premotor and motor cortices. The group of nuclei include the **striatum**, the **globus pallidus** (which is located medial to the putamen, consists of both an internal and external segment), the **substantia nigra** (which consists of the pars compacta), and the **subthalamic nucleus** (which rests above portios of the substantia nigra). The straitum is composed of the **caudate** and **putamen**, which are responsible for learning and memory, and regulating movements, respectively. These two nuclei are responsible for the most projections to the basal ganglia.
 * <span style="font-family: Georgia,serif;">Basal Ganglia **



<span style="font-family: Georgia,serif;">The cerebellum integrates inputs coming from the brain and spinal cord to play roles in movement-related functions, specifically fine-tuning motor activity (ie: coordination, precision). It consists of three distinct regions. The **vestibulocerebellum**, which is composed of the floculonodular lobe, is responsible for the control of balance and eye movements. The **spinocerebellum**, consisting of the intermediate hemispheres and the **vermis**, is responsibile for the control of proximal muscles and limbs, and of distal limbs and digits, respectively. The **cerebrocerebellum** is made up of the lateral hemispheres. Its projectins to motor, premotor, and prefrontal cortices help to explain its functions, which include its involvement in the planning of complex motor actions, and the evaluation of sensory information from errors for movement.
 * <span style="font-family: Georgia,serif;">Cerebellum **


 * RESEARCH **

<span style="font-family: Georgia,serif;">The localized brain regions involved in three core aspects of dance (including entratinment, meter, and patterned movement) as outlined by the study The Neural Basis of Human Dance have been localized and suggested as the following.

<span style="font-family: Georgia,serif;">Entrainment <span style="font-family: Georgia,serif;">This entrainment is specific to that of movement to external timekeepers, such as music. <span style="font-family: Georgia,serif;">The regions of the brain that are activated include the <span style="color: #008000; font-family: Georgia,serif;">anterior vermis of the anterior cerebellar lobule III <span style="font-family: Georgia,serif;">, along with the <span style="color: #008000; font-family: Georgia,serif;">right medial geniculate nucleus <span style="font-family: Georgia,serif;">. Figure 2 to the right is an image that reflects activation in the aforementioned brain regions when a study participant performed learned dance step movements to music being played while they were lying in the PET scanner.

<span style="font-family: Georgia,serif;">Patterned movement <span style="font-family: Georgia,serif;">This aspect of dance refers to the spatial navigation of lower-limb (leg) movement, causing the activation of several brain structures, including the <span style="color: #008000; font-family: Georgia,serif;">primary motor and somatosensory cortices, the premotor cortex, the supplementary motor area, and the somatotopic leg areas of the cerebellum (lobules IV and VIII) <span style="font-family: Georgia,serif;">. Specifically relating to the movement of limbs is activation in the inferior parietal lobule (IPL) during the observation, preparation or simulation of actions. The activity in this region is the most when dancers simulate actions that they have had prior experience to. <span style="font-family: Georgia,serif;">Also, specific to physical learning, activity in the premotor cortex is related to both the competency and learning aspsects of dance, as the right premotor cortex is specifically involved in being able to embody an action after it is rehearsed. In addition, activation which has also been seen in the cingulate motor area has been suggested to reflect that this region contains a somatotopic map.

<span style="font-family: Georgia,serif;">Meter <span style="font-family: Georgia,serif;">This aspect of dance is used to refer to the movement to rhythm that is regular and metric (as opposed to that which is irregular and non-metric). When metered movements are are carried out, the b <span style="font-family: Georgia,serif;">asal ganglia is seen to be activated. More specifically, a strong bilateral signal in the <span style="color: #008000; font-family: Georgia,serif;">putamen <span style="font-family: Georgia,serif;"> is seen.


 * <span style="font-family: Georgia,serif;">NEURONAL CONNECTIONS **


 * <span style="font-family: Georgia,serif;">Action Observation Network (AON) **

<span style="font-family: Georgia,serif;">Most likely linked to [|mirror neurons], which may help explain why and how we can copy an action that we see, is the AON. This is a network, which suggests an overall relationship between action and observation. The network itself includes neural connections shared by both physical rehearsal (action) and observational learning (observation) which is evidenced by similarities in neural activity. This activity is seen in premotor and inferior parietal regions, however specifically in regards to training (whether or not through passive observation or physical rehearsal). An interesting thing to note is that the AON is sensitive to these different types of training. In addition, although there are siginificant increases in learning when a dancer is told to study the movement for a time later on, such as a performance, even if the focus isn't of learning from observing, observational learning can still take place.


 * <span style="font-family: Georgia,serif;">The integration of brain areas to allow for dance **

<span style="font-family: Georgia,serif;">Despite different regions of the brain being activated for different aspects of dance, in order for dance to be performed, there is a coordination among these various areas that allow for the “bipedal, cyclically repeated dance steps entrained to a musical rhythm” (Brown et al. 2005).

<span style="font-family: Georgia,serif;">The following findings come directly from Brown et al. study, although other studies that have been performed appear to have similar results. <span style="font-family: Georgia,serif;">The melodic and harmonic aspects of the music that is listented to is represented by both the superior temporal gyrus and the superior temporal pole. Regarding the beat of the music, the medial geniculate nucleus seems to send inputs, via brainstem nuclei, to the anterior cerebellar vermis and lobules V and VI in order to support the entrainment of movement to the beat of the music. The basal ganglia, especially the putamen within it, is involved in the metric aspects of movement, whereas the thalamus plays a role to connect the somatosensory to the motor parameters, especially in regards to rhythms which are not-metric. Motion that is bipedal and repeated cyclically, requires coordination between the two limbs, which is supported by the supplementary motor area (SMA), the cingulated motor area, and the cerebellum. Lastly, the spatial guidance of leg movement is provided by the medial aspects of the superior parietal lobule.


 * <span style="font-family: Georgia,serif;">SUGGESTED IMPLICATIONS **

<span style="font-family: Georgia,serif;">The beneficial findings from studies exploring the connection between dance and the brain has led to the incorporation of dance in other aspects. This can be seen through the use of [|dance as therapy for individuals with Parkinson's Disease], whose benefits are explored through the study.


 * <span style="font-family: Georgia,serif;">SUMMARY **

<span style="font-family: Georgia,serif;">Research has revealed a lot about the regions and specific structures of the brain which are activated during dance. Much of these findings speak a lot about how a dancer of any level can transform what they observe into movements of their own, also giving an observor a deeper appreciation and understanding for dancing such as seen [|here] (This video is a representaion of the different aspects of ballet, but to an extreme, such as balance, patterned movement, and coordination in just one performance). In addition, they provide meaningful insights that can be applied to a population of non-dancers, who may benefit.


 * GLOSSARY OF TERMS **

<span style="font-family: Georgia,serif;">a network including neural connections shared by both physical rehearsal (action) and observational learning (observation), suggesting a relationship between action and observation <span style="font-family: Georgia,serif;">**Entrainment** (specific to movement) <span style="font-family: Georgia,serif;">a synchronization of movement to external timekeepers, such as music <span style="font-family: Georgia,serif;">a neuron that "mirrors" the behavior of the observed action as though it were carrying out that action itself <span style="font-family: Georgia,serif;">a nuclear medicine imaging technique which produces a 3-D image of the body's functional processes <span style="font-family: Georgia,serif;">an image representation of the parts of the primary somatosensory cortex responsible for the exchange of sensory information
 * <span style="font-family: Georgia,serif;">Action Observation Network (AON) **
 * <span style="font-family: Georgia,serif;">Mirror neurons **
 * <span style="font-family: Georgia,serif;">Positron Emitron Topography (PET) **
 * <span style="font-family: Georgia,serif;">Sensory homunculus **


 * <span style="font-family: Georgia,serif;">QUIZ **

<span style="font-family: Georgia,serif;">Multiple Choice <span style="font-family: Georgia,serif;">1. Which region of the brain integrates inputs coming from the brain and spinal cord to play roles in movement-related function? <span style="font-family: Georgia,serif;">a. basal ganglia <span style="font-family: Georgia,serif;">b. right supplementary motor area <span style="font-family: Georgia,serif;">c. cerebellum <span style="font-family: Georgia,serif;">d. posterior parietal cortex

<span style="font-family: Georgia,serif;">2. <span style="font-family: Georgia,serif;">Which nuclei of the basal ganglia is the most activated during regular and metric movement? <span style="font-family: Georgia,serif;">a. subthalamic nucleus <span style="font-family: Georgia,serif;">b. putamen <span style="font-family: Georgia,serif;">c. substantia nigra <span style="font-family: Georgia,serif;">d. striatum

3. Which structure plays a role to connect the somatosensory to the motor parameters? a. somatosensory cortex b. basal ganglia c. cerebellum d. thalamus

<span style="font-family: Georgia,serif;">﻿﻿True/ False <span style="font-family: Georgia,serif;">4. The 3 core aspects of dance include entrainments of movement to internal timekeepers, patterned movement, and irregular and non-metric movement.

<span style="font-family: Georgia,serif;">5. Training cannot occur through both passive observation and physical rehearsal.

<span style="font-family: Georgia,serif;">6. Mirror neurons are the name of the neurons located in the PMA which are activated during the preparation of movement.

<span style="font-family: Georgia,serif;">﻿Short Answer/Essay <span style="font-family: Georgia,serif;">From what you already know about dance, along with something new that you just learned, provide your own definiton of dance that incorporates its different components.

<span style="font-family: Georgia,serif;">How specifically can the findings of research translate to being helpful in populations outside of the dance community, such as seen with individuals with Parkinson's Disease?

<span style="font-family: Georgia,serif;">Answers <span style="font-family: Georgia,serif;">1. C <span style="font-family: Georgia,serif;">2. B <span style="font-family: Georgia,serif;">3. D <span style="font-family: Georgia,serif;">4. F <span style="font-family: Georgia,serif;">5. F <span style="font-family: Georgia,serif;">6. T


 * <span style="font-family: Georgia,serif;">FURTHER SUGGESTED READINGS **

<span style="font-family: Georgia,serif;">Badets, A., Y. Blandin, and C. H. Shea. (2006) Intention in motor learning through observation. Quarterly Journal of Experimental Psychology. 59:377-386 <span style="font-family: Georgia,serif;">This study attempts to answer the question of whether observational learning is enhanced when reproduction of the observed behavior is the intended goal.

<span style="font-family: Georgia,serif;">Calvo-Merino, B., D. E. Glaser, J. Grezes, R. E. Passingham, and P. Haggard. (2005) Action observation and acquired motor skills: an FMRI study with expert dancers. Cerebral Cortex 15:1243-1249. <span style="font-family: Georgia,serif;">[|Study available here:] <span style="font-family: Georgia,serif;">For more information on the 'mirror system', through this study performed on dancers, it answers the question of if and how our brain simulate the observed actions of someone else performing.

<span style="font-family: Georgia,serif;">Ehrsson, H. H., E. Naito, S. Geyer, K. Amunts, K. Zilles, H. Forssberg, and P.E. Roland. (2000) Simultaneous movements of upper and lower limbs are coordinated by motor representations that are shared by both limbs: a PET study. European Journal of Neuroscience 12:3385-3398 <span style="font-family: Georgia,serif;">[|Study available here] <span style="font-family: Georgia,serif;">This study specifically examines how limb movement is coordinated.

<span style="font-family: Georgia,serif;">[] <span style="font-family: Georgia,serif;">This is the link to Ivar Hagendoorn's website who as a choreographer, photographer, and researcher has contributed a significant amount to the research that looks at dance and the brain. <span style="font-family: Georgia,serif;">Brown, S., M. J. Martinez, and L. M. Parsons. (2006) The neural basis of human dance. Cerebral Cortex 16:1157-1167.
 * <span style="font-family: Georgia,serif;">References **

<span style="font-family: Georgia,serif;">Brown, S., and L. Parsons. (2008) So you think you can dance?:PET scans reveal your brain's inner choreography. Scientific American Magazine

<span style="font-family: Georgia,serif;">Cross, E. S., A. F. de C. Hamilton, and S. T. Grafton. (2006) Building a motor simulation de novo: observation of dance by dancers. Neuroimage 31:1257-1267

<span style="font-family: Georgia,serif;">Cross, E. S., D. J. M. Kraemer, A. F. de C. Hamilton, W. M. Kelley, and S. T. Grafton. (2009) Sensitivity of the action observation network to physical and observational learning. Cerebral Cortex 19:315-326

<span style="font-family: Georgia,serif;">NOVA. Mirror Neurons. Available from: []. Accessed: 16 December 2010.