To this cannabinoids strongly inhibit ejection of glutamate and certainly everyone in this forum can confirm that cannabinoids significantly sharpen the senses
The objective studies can confirm that cannabinoids are bad for short term memory specifically because of the issues with not receiving enough stimulation to remove the magnesium block - from wiki "
[18]NMDA receptors are believed to be involved in cellular hippocampal LTP and LTD processes, in respect to memory consolidation and forgetting factors.
[2][16] For these process to occur on the cellular level, a high enough excitatory postsynaptic potential must occur to
depolarize the CA1 hippocampal postsynaptic membranes and remove the magnesium blockade on NMDA receptors.
[19][20] Glutamate plays the role in activating NMDA receptors, allowing hippocampal
calcium to flow through NMDA receptor channels—calcium NMDA receptor transmission is critical in inducing both LTP and LTD.
[16][19] Optical imaging evidence that monitors synaptic activity on
in vitro hippocampal neurons, demonstrates that CB1 agonists (including THC) reduce glutamate release.
[21] Since glutamate release is required for NMDA receptor activation, and removing the magnesium blockade, a reduction of glutamate release causes a reduction of excitatory postsynaptic potential, suggesting an impairment of LTP and LTD is mediated via hippocampal NMDA receptors.
[16][19][20] This finding not only suggests that memory impairment affects long-term
synaptic plasticity, but is also supported via experimental data.
[16] In fact, research shows that CB1 agonists in the hippocampus do not impair LTP and LTD,
when the NMDA magnesium blockade is instrumentally removed on hippocampal CA1 neurons.
[22] Ultimately, with the consistency of scientific inference and experimental data, cannabinoid effects on memory are compellingly supported via the modulation of glutamate release.
[2][16][17]"