1. Reflexive covert attention: Voluntary covert attention:
Cerebellar contributions to reflexive and voluntary covert visual attention: Preliminary findings
Christopher Striemer1,2, Brandon Craig1, Britt Anderson3, & James Danckert3
Department of Psychology, MacEwan University, Edmonton, Alberta, Canada
Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
Department of Psychology, University of Waterloo, Waterloo, Ontario, Canada
Introduction Methods Results
Reflexive covert attention
The cerebellum is known for its important role in motor control (ref 1); however, more recent research suggests that the cerebellum is also involved in cognitive functions such as working memory, language, and attention (refs 2 & 3).
A recent fMRI study indicated that the left cerebellum is involved in covert attention; and may be more engaged during reflexive compared to voluntary attention tasks (ref 4)
10 patients with cerebellar stroke and 10 age-appropriate controls were recruited as part of an on-going study examining the effects of cerebellar lesions on cognition
Each patient and control completed reflexive and voluntary covert attention tasks:
Reflexive covert attention:
Cerebellar patients demonstrated a larger cueing effect at longer SOAs reflecting a slowed initiation of inhibition of return (IOR) (ref 6)
This may be related to damage to overlapping neural circuits that control attention and eye movements in the cerebellum (ref 4)
(ref 5)
(ref 4)
Voluntary covert attention:
Voluntary covert attention
Furthermore, damage to the oculomotor vermis, lobules V, VI, and Crus I/II result in deficits in covert attention (refs 6-8)
Patients are slower to orient attention at short SOAs (i.e., <100ms) but are unimpaired at longer SOAs (refs 6,8)
In addition, cerebellar patients may be slower to initiate inhibition of return (IOR) (ref 6)
Lesion Analysis L 1 2 3
There were no significant differences between cerebellar patients and controls for voluntary covert attention
Images of a normal cerebellum (1), left cerebellar lesion (2), and right cerebellar lesion (3).
Implications
Lesions (n=6) were manually traced in MRIcron using high resolution T1 anatomical images (1mm ISO voxels)
Lesion overlap analysis was performed using the SUIT toolbox in SPM 12 (ref 9)
Area of greatest overlap (currently n=6): left Crus II
Our preliminary results support the notion that damage to the lateral cerebellum slows the initiation of inhibition of IOR (ref 6)
Our preliminary data also suggest that the cerebellum may be more involved in reflexive compared to voluntary covert attention (ref 4) L R
References/Acknowledgements
1. Glickstein et al. (2009). Neuroscience, 162,
2. Stoodley and Schamahmann (2009). NeuroImage, 44,
3. Buckner (2013). Neuron, 80,
4. Striemer et al. (2015). Neuropsychologia, 69, 9-21.
5. Wang et al. (2013). Journal of Neurophysiology, 109,
6. Striemer et al. (2015). Frontiers in Human Neuroscience, 9, 1-10.
7. Baier et al., (2010). Journal of Neuroscience, 30,
8. Townsend et al. (1999). Journal of Neuroscience, 19,
9. Diedrichsen (2006). Neuroimage, 33,
Acknowledgments:
The authors would like to thank Nadine Quehl for her assistance with recruiting and testing the patients, and Drs. Joern Diedrichsen and Carlos Hernandez for their assistance with the lesion analysis.
In the current study we are comparing the effects of cerebellar lesions (currently n=10) on reflexive and voluntary covert visual attention
We are also performing a lesion analysis to examine which regions of the cerebellum are involved in reflexive and voluntary covert attention