On Mon, 30 Jan 1995, Freddie wrote:
>> > The second mechanism is much more heavily studied and involves storing
> > information within the synapses by adjusting their strength. This is
> > thought to occur by increasing the amount of transmitter released from the
> > presynaptic terminal or by increasing the postsynaptic response to a given
> > amount of transmitter, or through both mechanisms (see Churchland and
> > Sejnowski, The Computational Brain).
>> Neuromodulators affect the PSP of a given amount of neurotransmitter.
> Are neuromodulators know to have an effect on memory? If
> neuromodulator were administered to a human subject would it not have a
> tremendous impact on memory for the time it is active?
>Freddie,
There's quite an extensive literature on the effect of neuromodulators on
memory. The most interesting recent work comes from McGaugh, who has
studied the effect of the adrenergic system on memory retention. As I
remember the data, beta blockers in the amygdala block the retention of
shock-conditioned contextual learning (a presumptively hippocampally
mediated spatial learning assay). Interestingly, beta blockers also
blocked the improved memory for unrelated events in a story with a
horrifying event recounted (a boy having his legs by a car on the way to
visit someone in a hospital) compared to memory for the same peripheral
events in an ordinary visit without this event.
Mark Barad
