The organization of the human cerebellum estimated by intrinsic functional connectivity

Abstract

The organization of the human cerebellum estimated by intrinsic functional connectivity. J Neurophysiol 106: 2322-2345. First published July 27, 2011 doi:10.1152/jn.00339.2011The cerebral cortex communicates with the cerebellum via polysynaptic circuits. Separate regions of the cerebellum are connected to distinct cerebral areas, forming a complex topography. In this study we explored the organization of cerebrocerebellar circuits in the human using restingstate functional connectivity MRI (fcMRI). Data from 1,000 subjects were registered using nonlinear deformation of the cerebellum in combination with surface-based alignment of the cerebral cortex. The foot, hand, and tongue representations were localized in subjects performing movements. fcMRI maps derived from seed regions placed in different parts of the motor body representation yielded the expected inverted map of somatomotor topography in the anterior lobe and the upright map in the posterior lobe. Next, we mapped the complete topography of the cerebellum by estimating the principal cerebral target for each point in the cerebellum in a discovery sample of 500 subjects and replicated the topography in 500 independent subjects. The majority of the human cerebellum maps to association areas. Quantitative analysis of 17 distinct cerebral networks revealed that the extent of the cerebellum dedicated to each network is proportional to the network's extent in the cerebrum with a few exceptions, including primary visual cortex, which is not represented in the cerebellum. Like somatomotor representations, cerebellar regions linked to association cortex have separate anterior and posterior representations that are oriented as mirror images of one another. The orderly topography of the representations suggests that the cerebellum possesses at least two large, homotopic maps of the full cerebrum and possibly a smaller third map. somatotopy; motor control; prefrontal; functional magnetic resonance imaging; default network; connectome THE ORGANIZATION OF THE CEREBELLUM has been the topic of debate for more than a century (Manni and Petrosini 2004). Although there is agreement that the cerebellum contains multiple somatomotor representations, a challenging feature of cerebellar anatomy prevents resolving its complete organization: the cerebellum is connected to the cerebral cortex only by way of polysynaptic circuits (Evarts and Thach 1969;Kemp and Powell 1971;Schmahmann and Pandya 1997a;Strick 1985). Efferent projections from the cerebrum synapse initially in the pontine nuclei and then project primarily to the contralateral cerebellar cortex (the pontocerebellar tract). Afferent projections first synapse in the deep cerebellar nuclei (e.g., dentate nucleus) and then project to a second synapse in the contralateral thalamus that in turn serves as a relay to the cerebral cortex (the dentatothalamocortical tract). There are no monosynaptic connections between the cerebrum and cerebellum. As a result, traditional anterograde and retrograde tracing techniques cannot be u...

Temperature and CO2additively regulate physiology, morphology and genomic responses of larval sea urchins,Strongylocentrotus purpuratus

“…13°C, 400 matm 13°C, 1100 matm 18°C, 400 matm 18°C, 1100 matm rspb.royalsocietypublishing.org Proc R Soc B 280: 20130155 pCO 2 is a strong indicator that skeletogenesis is impaired in high pCO 2 sea water and provides a mechanistic explanation for reductions in larval size at elevated pCO 2 [62]. Our results indicate that simultaneous exposure to warmer and more acidic environments can trigger metabolic depression in S. purpuratus.…”

‘O’ blood type is associated with larger grey-matter volumes in the cerebellum

“…This finding emerged from both Model 1 and Model 2, suggesting that this region might be the preferential regional locus of an 'O' endophenotype. The two outcome clusters overlapped with good accuracy with the cerebellar regions known to be part of a cerebro-cerebellar network responsible for sustaining sensorimotor integration (Buckner et al, 2011). Although this is not a functional circuit primarily involved in the most common forms of dementia of major aetiology (Seeley et al, 2011), a significantly smaller ABO-related GM volume in these areas might concur in fostering vulnerability for cognitive decline in old age.…”

High‐angular resolution diffusion imaging tractography of cerebellar pathways from newborns to young adults

“…MCP mot is predominantly associated with motor‐sensory function, originates in the caudal pons and runs superior‐medially toward the anterior cerebellum. Past studies have found evidence of a rostral pons to posterior cerebellum and caudal pons to anterior cerebellum connection (Schmahmann, Rosene, & Pandya, 2004; Spitzer & Karplus, 1907; Sunderland, 1940; Von Bechterew, 1885), which is further supported by evidence that points to a caudal pons anterior lobe of cerebellum sensorimotor representation (Buckner, Krienen, Castellanos, Diaz, & Yeo, 2011; Schmahmann, MacMore, & Vangel, 2009; Schmahmann & Pandya, 1997; Schmahmann & Sherman, 1998; Stoodley & Schmahmann, 2010). The superior cerebellar peduncle pathway (SCP) consists primarily of efferent output neurons traveling from the cerebellum to higher brain centers via the mid‐brain (Hüttlova et al., 2014; Mittal et al., 2014; Ojemann et al., 2013; Schmahmann et al., 2004; Takahashi, Song, Folkerth, Grant, & Schmahmann, 2013; Von Bechterew, 1885; Wang et al., 2003).…”