PSYCHEDELICS - Sciencemadness.org

209___________
____________________________________________________ Psychedelics
Figure 4. Effect of LSD-25 on synaptic transmission in the cerebral
cortex of the cat. The response, recorded from the visual
projection area, was produced by electrical shock to optic radiation.
This response shows several typical deflections, the discussion
of whose origin is beyond the scope of this paper. A: control,
B: after injecting 1.5 mg of LSD-25 into the carotid artery.
Note particularly the increase of late components after the drug
(from Evarts et al., 1955).
It seems that more work is needed to clarify this and other
questions arising from experimental data obtained so far.
Still, of interest in view of Evarts' results are the observations
of Blough (1957). This author, using a rather intricate
behavioral test arrangement, was able to measure the "absolute
visual threshold" in pigeons. When the birds were given