Bilateral Multi-Electrode Neurophysiological Recordings Coupled to Local Pharmacology in Awake Songbirds

Here we describe a protocol for bilateral multielectrode neurophysiological recordings during intracerebral pharmacological manipulations in awake songbirds. This protocol encompasses fitting adult animals with head-posts and recording chambers, and acclimating them to periods of restraint. The adaptation period is followed by bilateral penetrations of multiple electrodes to obtain acute, sensory-driven neurophysiological responses before versus during the application of pharmacological agents of interest. These local manipulations are achieved by simultaneous and restricted drug infusions carried out independently for each hemisphere. We have used this protocol to elucidate how neurotransmitter and neuroendocrine systems shape the auditory and perceptual processing of natural, learned communication signals. However, this protocol can be used to explore the neurochemical basis of sensory processing in other small vertebrates. Representative results and troubleshooting of key steps of this protocol are presented. Following the animal\u27s recovery from head-post and recording chamber implantation surgery, the length of the procedure is 2 d

Trauman monet kasvot : trauman kuvaamista kuvataiteen keinoilla

Taiteellinen produktio kuvasi ja tutki voiko trauman nähdä ja miltä se voisi näyttää kasvoilla. Päämateriaali oli väritön lasi, josta tehtiin pienikokoisia lasikasvoja 52 kappaletta kiventyöstön menetelmillä. Lasipalojen pintaan luonnosteltiin kasvonpiirteitä. Teos esitettiin installaationa käyttäen ilmaisuun valoa, jonka avulla teoksesta syntyi heijastuksia ja varjoja näyttelytilaan

State and neuronal class-dependent reconfiguration in the avian song system

Sensory systems may adapt to behavioral requirements through state-dependent changes. In the forebrain song-system nucleus HVc of zebra finches, state-dependent auditory responses have been described in multiunit recordings. Here we report on behavioral state-dependent changes in the activity of distinct HVc neuronal classes. HVc projection neurons were identified by electrically stimulating HVc's target nuclei, the robust nucleus of the archistriatum and Area X, in anesthetized zebra finches. Projection neurons and two classes of putative interneurons could be distinguished on the basis of extracellular spike waveforms, with the first two factors of a principal components analysis accounting for 81% of the variance in spike morphometric values. Spike width was the best single variable for distinguishing among the neuronal classes. Putative interneurons had much higher firing rates spontaneously and in response to song than did projection neurons, which had extremely low spontaneous rates and phasic responses to song. Recordings from HVc in behaving animals were dominated by the two classes of putative interneurons. Both classes showed strong, selective, and temporally similar auditory responses during sleep, but only one class of interneurons reliably maintained auditory responses on waking. These responses were weaker and less selective than those seen during sleep. The observation that HVc auditory responsiveness in awake zebra finches is restricted to some classes of neurons may help explain prior multiunit results that suggested nearly complete suppression of HVc auditory responses in awake birds. We propose that the heterogeneous effects of behavioral state on distinct subpopulations of HVc neurons allow HVc to participate in multiple roles during song production, conspecific song recognition, and possibly memory consolidation during sleep