In Collaboration with Several Carnegie Mellon University Faculty, Dr Quinlan is Published in PNAS
The Effect of Midazolam on Visual Search:
Implications for Understanding Amnesia
Proc Natl Acad Sci U S A. 2004 Dec 21;101(51):17879-83.
Epub 2004 Dec 13
"The notion of multiple memory systems based on conscious accessibility
has been supported largely by neuropsychological patient studies.
Specifically, it was widely held that amnesic patients have impaired
explicit memory performance but spared implicit memory performance.
However, recent patient studies have called the implicit/explicit
memory distinction into question. In this study, normal participants
were tested on a visual search task, once after an injection
of midazolam, an anesthetic that induces temporary amnesia, and
once after an injection of saline. Under the influence of midazolam,
participants did not show facilitation in search times for repeated
configurations (contextual cuing), although there was a general
speed-up in performance across blocks in both the midazolam and
saline conditions. Neither the contextual-cuing effect nor the
procedural-learning effect was available to subjective experience,
yet only one of these was affected by midazolam-induced amnesia.
These data call into question the notion that memory systems
divide on the basis of subjective experience of consciousness
or reportability. Rather, the findings support the contention
that anterograde amnesia affects learning that depends on building
novel associations in memory and that this deficit does not hinge
upon accessibility to consciousness." [more]