Activity of brainstem cholinergic neurons during 22 kHz ultrasonic vocalization in rats /

Adult rats emit 22 kHz ultrasonic alann calls in aversive situations. This type of call IS a component of defensive behaviour and it functions predominantly to warn conspecifics about predators. Production of these calls is dependent on the central cholinergic system. The laterodorsal tegmental nucleus (LDT) and pedunculopontine tegmental nucleus (PPT) contain largely cholinergic neurons, which create a continuous column in the brainstem. The LDT projects to structures in the forebrain, and it has been implicated in the initiation of 22 kHz alarm calls. It was hypothesized that release of acetylcholine from the ascending LDT terminals in mesencephalic and diencephalic areas initiates 22 kHz alarm vocalization. Therefore, the tegmental cholinergic neurons should be more active during emission of alarm calls. The aim of this study was to demonstrate increased activity of LDT cholinergic neurons during emission of 22 kHz calls induced by air puff stimuli. Immunohistochemical staining of the enzyme choline acetyltransferase identified cell bodies of cholinergic neurons, and c-Fos immunolabeling identified active cells. Double labeled cells were regarded as active cholinergic cells. There were significantly more (p

Motivation and psychological need salience in the experiences of initiating and maintaining exercise as an older female adult

Objectives: The primary objective ofthis study was to explore motivation and psychological need salience in the initiatory and maintenance experiences of older female exercIsers. Methods: Female initiates (n = 3) and reflective maintainers (n = 3) 65 years of age or older (M = 76 years; SD = 5.37) participated in semi-structured interviews. Data were analyzed holistically and categorically, following a hermeneutic approach to inquiry. Results: Perceived importance of exercise benefits appeared to be the strongest motive for initiates at this stage of life and connections to others were perceived as valued, but less important in exercise contexts. Also, listening to one's body over instructions from the exercise leader emerged as a key factor to success. Conclusions: Overall, the results ofthis study implicate more self-determined than controlled motives as sources of regulation in older females' exercise initiation experiences. Evidence for psychological needs was more heterogeneous and less conclusive.