Publications by authors named "Alexandra L Sommer"
Objective: Status epilepticus (SE) significantly increases the risk for the development of unprovoked seizures, memory loss, and temporal lobe epilepsy. Our prior studies showed that SE increases complement C3 signaling in the hippocampus, which parallels memory deficits. Additionally, C3 knockout (KO) mice were protected against SE-induced memory impairments, suggesting a mechanistic role for C3 in this pathophysiology.
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- Episodic memories are structured around event boundaries, which are times of environmental change, requiring the brain to rapidly reset for effective information encoding.
- Norepinephrine (NE) is believed to help reorganize neuronal networks during these changes, but its role in the hippocampus during event boundaries is still being explored.
- Research using a new sensor to measure NE in mice showed that NE release coincides with these environmental transitions, affecting hippocampal neural spiking patterns and potentially aiding long-term memory formation.
Article Synopsis
- Events of status epilepticus (SE) can lead to the development of temporal lobe epilepsy (TLE), which often results in cognitive impairments and memory defects due to hippocampal injury.
- A study suggests that the proliferation of reactive microglia after SE plays a role in these cognitive deficits, and treatment with the CSF1R inhibitor PLX3397 could potentially alleviate these issues.
- In their experiments, both control and SE rats receiving PLX3397 showed reduced microglial numbers and improved memory function; however, SE rats still displayed significant memory deficits compared to controls, indicating that while microglial targeting may help, it doesn't fully resolve the cognitive impairments associated with SE.
Article Synopsis
- Status epilepticus (SE) is a serious condition where prolonged seizures can lead to brain damage and cognitive decline, potentially due to overactivation of the classical complement pathway.
- Researchers hypothesized that blocking this pathway with a drug called C1 inhibitor (C1-INH) immediately after SE could prevent related learning and memory issues.
- Experimental results showed that rats treated with C1-INH after SE regained weight and mobility better than those that did not receive the treatment, suggesting a protective effect on cognitive functions following seizures.
Previous work has debated about the comparisons of hearing abilities faced with alterations in hearing thresholds and evoked potentials between groups following acoustic trauma- or age-related changes. This study compares envelope-following responses (EFRs) of young and aged rats when sound levels were matched according to (1) wave I amplitudes of auditory brainstem responses (ABRs) elicited by 8-kHz tones or (2) EFR amplitudes evoked by sinusoidally amplitude-modulated (SAM) tones at 100% depth. Matched wave I amplitudes across age corresponded to approximately 20-dB sound level differences.
View Article and Find Full Text PDFParticle swarm optimization (PSO) has gained widespread use as a general mathematical programming paradigm and seen use in a wide variety of optimization and machine learning problems. In this work, we introduce a new variant on the PSO social network and apply this method to the inverse problem of input parameter selection from recorded auditory neuron tuning curves. The topology of a PSO social network is a major contributor to optimization success.
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