Perirhinal cortex (PR) is part of the cerebral cortex in the mammalian medial temporal lobe. Though it has been implicated in a variety of behaviors and exhibits pathology in many clinically ...important disorders (such as Alzheimer's disease, schizophrenia, and aging-related cognitive decline), little is known about the cellular neurobiology of the region. Whole-cell electrical recordings from individual neurons in PR in living slices of rat brain revealed an extraordinary abundance of late-spiking (LS) neurons, which typically delay for several seconds after the onset of stimulation before beginning their spike train. Layer VI of PR was found to be composed almost entirely of LS neurons, and to contain virtually no regular- or burst-spiking neurons, which are the primary cell type in other cortical regions. A series of theoretical studies were conducted to evaluate the potential function of this remarkable cortical specialization, in particular the role that this region might play in classical fear conditioning, which requires seconds-range temporal processing and is PR-dependent. In fear conditioning, the subject is presented with a conditioned stimulus (CS), typically an auditory tone, followed several seconds or tens of seconds later by an aversive unconditioned stimulus (US), typically an electric shock. A computational model based on the observed neurobiology of PR and the neighboring amygdala found that the LS neurons in PR could provide a sufficient mechanism for the representation of the CS during the CS-US interstimulus interval (ISI), as well as encoding the time elapsed since CS onset. Testing of this model revealed that it predicted conditioned responses with appropriate temporal form, including the independent learning of CS-US dependencies at different ISIs and decreasing temporal precision at longer latencies. In addition, the inclusion of intra-amygdalar circuitry causes the observed dependence of overall conditioning effectiveness on the training ISI to emerge naturally from random fluctuations in synaptic amplitude and intrinsic neuronal biophysics.
I examine how academic discourse has historically been foundational in its orientation, meaning that it originated with the search for truth apart from human experience, which has resulted in the ...subordination of personal writing in composition and rhetoric. This subordination has created what feminists call the private-public dichotomy. Drawing on the work of feminists who have incorporated personal storytelling into their academic writing, I argue for a reformulation of the standards of academic discourse to include both personal and public forms of writing in scholarly work. Such a reformulation would dissolve the private-public dichotomy by placing the personal within political, cultural perspectives, moving us away from the individualization of experience. I attempt to join both personal and public forms of discourse by connecting my academic work with stories of my personal struggle between my public self--the Critic, who assumes male authority--and a more private, vulnerable self dominated by the Critic--the Idiot.
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