Auditory processing assessment suggests that Wistar audiogenic rat neural networks are prone to entrainment

Seizure Susceptibility Corrupts Inferior Colliculus Acoustic Integration

“…Conversely, PTZ for Wistars seemed to have had the same effect (Figure 3F); however, if one considers its effect on Total Energy as well (Figures 3H–K), it is likely due to non-specific increased excitability within the 30 Hz spectral range. The 90 Hz modulation frequency of WARs has a clear increase in energy, particularly when normalized by baseline EEG (graph not shown—90 Hz normalized energy: t (17) = 2.2, p = 0.03—Unpaired t -test, Wistar-Saline, and WAR-Saline) corroborating results from the transient response (Figure 3C) and previous work from our group (Pinto et al, 2017). In addition, DZP promoted a significant increase in coherence (Figure 3D) for both strains, suggesting that gabaergic system enhancement facilitates the network entrainment by external stimuli, possibly by compromising IC top-down modulation.…”

“…The ASSR was used to evaluate network integration by entraining a distinct spectral signature on circuits processing auditory information. The WAR’s elevated power (ASSR frequency) in the preconditioning and test phases (paired and unpaired protocols), suggests an increased recruitment of neural networks processing the sound stimuli (Figures 2D,F); which could also be explained by higher synchronicity in neuronal population discharge (Kudela et al, 2003; Medeiros and Moraes, 2014) and confirms previous findings from our laboratory (Pinto et al, 2017). Nevertheless, the coherence data does not show significantly enhanced (Figures 2E,G) when comparing Wistar and WARs.…”

Top Common Differentially Expressed Genes in the Epileptogenic Nucleus of Two Strains of Rodents Susceptible to Audiogenic Seizures: WAR and GASH/Sal

“…The inferior colliculus (IC) is the main structure involved in the development of seizures in the audiogenic models, considered the epileptogenic nucleus (8)(9)(10)(11). Experiments in the WAR model demonstrated the importance of this structure in the initiation of the audiogenic seizures (12,13), and the immunoreactivity of the neural activity marker, c-Fos, was observed in the IC of WAR and GASH/Sal animals following seizures (8,14). In addition to the behavioral similarities, it is believed that other aspects are shared between the two audiogenic models.…”

A Custom Microcontrolled and Wireless-Operated Chamber for Auditory Fear Conditioning

“…The CS used in the CFC was a 10 kHz pure tone with its amplitude modulated by a sine wave of 53.7 Hz. These specific tone features were chosen based on previous results (Lockmann et al, 2017; Pinto et al, 2017).…”

“…Although the laboratory equipments designed to perform such associative learning protocols are supposedly fairly simple, the price can be prohibitive for small budget projects and they are usually quite inflexible in terms of controlling and programing the stimuli. The latter may constitute a drawback for the design of customized behavioral paradigms which may use pure tones to investigate the coding of sensory information (Liu et al, 2006; Tsytsarev et al, 2009) or even amplitude modulated stimuli tones in order to isolate neural circuitry involved in the sensory processing by means of steady state evoked responses (Lockmann et al, 2017; Pinto et al, 2017). In addition, the study of more complex cognitive and behavioral processes becomes impracticable, since they require more sophisticated and robust means of controlling contextual parameters and interacting with the animals (Cushman et al, 2013).…”