Its been said by some "experts" all people will infact develop parkinson if they live long enough. Thats one of the few know health benfits of smoking. Smokers seem to develop parkinson less often than other groups. Though they also tend to die younger to so I'm not sure if that was factored in the data. African Americans are less likley to develop parkinson compared to whites. Oh back to smoking nicotine has an effect on dopamine plus tobacco also has a MAO-B inhibitor. Smokers typically have 40% inhibition of MAO-B which means they are on a anti-parkinson drug. Selegiline is known to be neuroprotective. It prevents/reduces that unavoidable parkinson that we
will all theoretically develop if we live long enough. So its possible tobacco has the same mechanism of action.
I would not be so quick to discount the realtionship between earily onset parkinson and autism the OP is suggesting. If a person had less dopamine neuron density from the beginning of their life in a number of areas of their brains such as one that control motor functions and other location related to social cogntion . Then one could theorise
a single genetic factor could put a person at risk of both autism and earily onset parkinson. I remember one study in with dopamine activity was less in social phobics.
As Rdos would suggest there is some strong overlap between social phobia and aspergers.
Quote:
Striatal Function in Generalized Social Phobia: A Functional Magnetic Resonance Imaging Study.
Sareen J, Campbell DW, Leslie WD, Malisza KL, Stein MB, Paulus MP, Kravetsky LB, Kjernisted KD, Walker JR, Reiss JP.
Department of Psychiatry.
BACKGROUND: Although evidence suggests the involvement of the amygdala in generalized social phobia (GSP), few studies have examined other neural regions. Clinical, preclinical, and dopamine receptor imaging studies demonstrating altered dopaminergic functioning in GSP suggest an association with striatal dysfunction. This is the first functional magnetic resonance imaging (fMRI) study to use a cognitive task known to involve the striatum to examine the neural correlates of GSP. We examined whether subjects with GSP had differential activation in striatal regions compared with healthy control subjects while engaged in a cognitive task that has been shown to activate striatal regions reliably. METHODS: Ten adult, unmedicated subjects with a primary DSM-IV diagnosis of GSP and 10 age-, gender-, and education-matched healthy comparison subjects underwent fMRI while performing the implicit sequence learning task. RESULTS: The GSP and healthy comparison subjects did not differ significantly on the behavioral performance of the task. Subjects with GSP, however, had significantly reduced neural activation related to implicit learning compared with healthy comparison subjects in the left caudate head, left inferior parietal lobe, and bilateral insula. CONCLUSIONS: These findings support the hypothesis that GSP is associated with striatal dysfunction and further the neurobiological understanding of this complex anxiety disorder.
PMID: 17097072 [PubMed - as supplied by publisher]
Quote:
Am J Psychiatry. 1997 Feb;154(2):239-42.
Links
Comment in:
Am J Psychiatry. 2001 Feb;158(2):327-8.
Dopamine reuptake site densities in patients with social phobia.
Tiihonen J, Kuikka J, Bergstrom K, Lepola U, Koponen H, Leinonen E.
Department of Forensic Psychiatry, University of Kuopio, Finland.
OBJECTIVE: It has been suggested that social phobia is associated with dysfunction of the noradrenergic and dopaminergic systems, but there are no published anatomic data on the monoaminergic abnormalities found in the brains of phobic patients. The authors studied the density of dopamine reuptake sites in patients with social phobia. METHOD: The study included 11 patients with social phobia and 28 healthy comparison subjects, 11 of whom were age- and gender-matched to the patients for the analyses. Measurement of the density of dopamine reuptake sites was performed by using a 123I-labeled cocaine analogue, [123I]beta-CIT, with single photon emission computed tomography (SPECT). RESULTS: Blind quantitative analysis revealed that striatal dopamine reuptake site densities were markedly lower in the patients with social phobia than in the age- and gender-matched comparison subjects. CONCLUSIONS: The results indicate that social phobia may be associated with a dysfunction of the striatal dopaminergic system.
PMID: 9016274 [PubMed - indexed for MEDLINE]
11 Jan 2007, 4:00 pm
