PMID-20855421[0] Mapping Go-No-Go performance within the subthalamic nucleus region.
- Support the dorsal-ventral motor-cognitive model.
- Only ventral subthalamic stimulation effected Go-No-Go accuracy.
- Both ventral and dorsal stimulation showed positive motor effects.
- On inhibition in the STN: (Aron and Poldrack 2006; Frank et al 2007).
- Thought: if methamphetamine and L-Dopa have similar impulsivity / punding / hobbyism effects, why do they think that the function is localized exclusively in the STN? These behaviors seem a more general problem of dopamine disregulation. Meth heads presumably have intact STN. The pausing hypothesis (e.g. STN controls pausing in conflict situations) seems better to me (maybe); have to check rat results.
- Such is the problem with taking one thing out of a feedback loop and assuming the resultant deficit corresponds with the original 'function' insofar as one can be assigned. Think if you adjust the coefficients on a filter -- it gets all F'ed, with minor projection onto the frequency response.
- Low-order systems are less sensitive to drastic parameter adjustment, but still purpose is obscured in feedback systems.
- See {1082}
- STN DBS can lead to impaired withholding strong prepotent responses with strong response conflict
- Such as the Stroop task (Jahanshahi et al 2000; Schroeder et al 2002; Witt et al 2004)
- Stop signal task (Ray et al 2009)
- Go-nogo tasks (Hershey et al 2004; Ballanger et al 2009).
- Rats show the same deficit in inhibiting responses in strong conflict cases (Baunex et al 1995, 2001; Baunez and Robbins 1997).
- Suggest that significant variability in treatment responses could be from the exact location of stimulation.
- Ventral STN closer to SNr, and dorsal is closer to the ZI and thalamus.
____References____
[0] Hershey T, Campbell MC, Videen TO, Lugar HM, Weaver PM, Hartlein J, Karimi M, Tabbal SD, Perlmutter JS, Mapping Go-No-Go performance within the subthalamic nucleus region.Brain 133:Pt 12, 3625-34 (2010 Dec) |
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