Posted by desolationrower on May 24, 2009, at 20:21:49
In reply to Re: Am I bipolar? Someone please....advice, posted by garnet71 on April 27, 2009, at 17:26:35
hm i'm visiting parents so i got out my laptop. heres this thread open, finially going to respond:
> Oh I'll tell you about the procrastination later. Yeah-I only took 1/2 dose of dextro, but it was odd that by the 3rd day, I didn't really feel it after a noticable affect on days 1 and 2. I'm trying to conserve my pills...no pdoc appt. for 2 mos.
>
> I want to know your thoughts on this (about the tonic and phasic DA..in relation to ADD (so I can think more about meds)) (except for swrings.lol):
>well, lol, remember this post? http://www.dr-bob.org/babble/20090313/msgs/886351.html
> > > "there is too much up and down in enjoyment level (ie, DA swrings, too little tonic DA).."
> > >
>
> I never read ADD/ADHD scientific lit, but just websites..but I think I've learned more about it from you than from anywhere else.me knowing things is just 'drug seeking behavior' though, 'talk to your doctor' lol.
here are two abstracts which summarise it
Afferent modulation of dopamine neuron firing differentially regulates tonic and phasic dopamine transmission., Floresco 2003
The mesolimbic dopamine system is centrally involved in reward and goal-directed behavior, and it has been implicated in multiple psychiatric disorders. Understanding the mechanism by which dopamine participates in these activities requires comprehension of the dynamics of dopamine release. Here we report dissociable regulation of dopamine neuron discharge by two separate afferent systems in rats; inhibition of pallidal afferents selectively increased the population activity of dopamine neurons, whereas activation of pedunculopontine inputs increased burst firing. Only the increase in population activity increased ventral striatal dopamine efflux. After blockade of dopamine reuptake, however, enhanced bursting increased dopamine efflux three times more than did enhanced population activity. These results provide insight into multiple regulatory systems that modulate dopamine system function: burst firing induces massive synaptic dopamine release, which is rapidly removed by reuptake before escaping the synaptic cleft, whereas increased population activity modulates tonic extrasynaptic dopamine levels that are less influenced by reuptake.Phasic versus tonic dopamine release and the modulation of dopamine system responsivity: a hypothesis for the etiology of schizophrenia., Grace 1991
A novel mechanism for regulating dopamine activity in subcortical sites and its possible relevance to schizophrenia is proposed. This hypothesis is based on the regulation of dopamine release into subcortical regions occurring via two independent mechanisms: (1) transient or phasic dopamine release caused by dopamine neuron firing, and (2) sustained, "background" tonic dopamine release regulated by prefrontal cortical afferents. Behaviorally relevant stimuli are proposed to cause short-term activation of dopamine cell firing to trigger the phasic component of dopamine release. In contrast, tonic dopamine release is proposed to regulate the intensity of the phasic dopamine response through its effect on extracellular dopamine levels. In this way, tonic dopamine release would set the background level of dopamine receptor stimulation (both autoreceptor and postsynaptic) and, through homeostatic mechanisms, the responsivity of the system to dopamine in these sites. In schizophrenics, a prolonged decrease in prefrontal cortical activity is proposed to reduce tonic dopamine release. Over time, this would elicit homeostatic compensations that would increase overall dopamine responsivity and thereby cause subsequent phasic dopamine release to elicit abnormally large responses.i'm not exactly sure how schizophrenia and adhd overlap. adhdi and negative symptoms seem to be similar, and probably relate to low catecholamines in the pfc, but there are probably differences in the developemental path and genetic causes, and in the adult limbic system. there are probably additional problems in large-scale connection in schizophrenia that cause the specific cognitive symptoms.
here are a few other studies:
http://www.csbmb.princeton.edu/ncc/publications/2002/CohenBraverBrown2002.pdf
http://amysantamaria.googlepages.com/NPP-pub.pdf <-i think the best one on catecholamines and computational models. i might have a different one on my other computer. i need to organize between the two eventually.
http://www.csbmb.princeton.edu/ncc/publications/2005/AstonJonesAnnRev2005.pdf <-review of noradrenaline/LC system. even has eye dilation graph.
also relevent:
In CNS dopamine is a slow-acting molecule; however,
the pattern of DA firing is functionally significant. It is
possible to differentiate single-spike firing (which can be
divided into regular and random types [58,59]), burst type
firing, which releases a higher amount of DA [60] and
colocalized peptides [61], and is able to activate early
immediate genes in target regions [62], and tonic activity.
The phasic component has been subdivided into a fast
(100300 ms) and slow (smin) components, the first being
involved in reward prediction error, the second in
reinforcement, sex, movement, punishment and stress
[63]. An increased DA release has been shown in the
nucleus accumbens during behavioural activation [64] and a
previous study investigated the involvement of the MCL
and MS DA systems in the control of activity, orienting,
scanning times towards environmental stimuli and emotional
reactivity in mouse model systems.
http://www.bnl.gov/thanoslab/Thanos%20PDF/DR%20review.pdf> Yeah, that sure makes sense...stuck w/unproductiivty and not being busy and excited.yeah, functioning and overwhelming.. that's sound exactly what it is right now.
>
> After I read this earlier today--I thought, well my life has been quite different over the past year--and I have gotten worse. No traveling for one year, no dating, change in types of course material to less appealing subjects (less contextual-more mathematical/scientific--and I am a creative person), less going out with friends, nothing exciting going on w/my life anymore compared to how I've lived in the past.
>
> I really learned a lot from this whole thread, about myself. I love this forum. :-) Hey, do you have ADD-I, or ADHD, or ADD mixed, or whatever..which one do/did you have? I never had ADHD, but my son did; he grew out of the H in ADD...but I've only had ADD-but do all that squirming and fidgeting in class stuff...lol
>i've never been hyperactive, or at least not much. i think i was mildly disruptive in school, but more of a 'asking questions i knew would flummox the teacher" not the usual sort of thing. and i fidget. not sure what role anxiety plays in that tho.
-d/r
poster:desolationrower
thread:891704
URL: http://www.dr-bob.org/babble/20090524/msgs/897506.html