Alice Schade Powers

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Fear conditioning represents the process by which a neutral stimulus comes to evoke fear following its repeated pairing with an aversive stimulus. Although fear conditioning has long been considered a central pathogenic mechanism in anxiety disorders, studies employing lab-based conditioning paradigms provide inconsistent support for this idea. A(More)
The standard nomenclature that has been used for many telencephalic and related brainstem structures in birds is based on flawed assumptions of homology to mammals. In particular, the outdated terminology implies that most of the avian telencephalon is a hypertrophied basal ganglia, when it is now clear that most of the avian telencephalon is(More)
We believe that names have a powerful influence on the experiments we do and the way in which we think. For this reason, and in the light of new evidence about the function and evolution of the vertebrate brain, an international consortium of neuroscientists has reconsidered the traditional, 100-year-old terminology that is used to describe the avian(More)
Hyperexcitable reflex blinks are a cardinal sign of Parkinson's disease. We investigated the neural circuit through which a loss of dopamine in the substantia nigra pars compacta (SNc) leads to increased reflex blink excitability. Through its inhibitory inputs to the thalamus, the basal ganglia could modulate the brainstem reflex blink circuits via(More)
Many vertebrates generate blinks as a component of saccadic gaze shifts. We investigated the nature of this linkage between saccades and blinking in normal humans. Activation of the orbicularis oculi, the lid closing muscle, EMG occurred with 97% of saccadic gaze shifts larger than 33°. The blinks typically began simultaneously with the initiation of head(More)
The distribution of cholinergic neurons was studied in painted and red-eared turtles using antisera against choline acetyltransferase (ChAT). The results showed that the organization of cholinergic systems in the central nervous system of turtles was remarkably similar to that previously described in diverse other species. For example, the present studies(More)
A stereotaxic atlas of the telencephalon, diencephalon and mesencephalon of a turtle (Chrysemys picta picta) is presented. A description is given of the procedures employed in the construction of the atlas and a few suggestions are offered as to possible uses. The importance of the study of the turtle in the comparative approach is emphasized.
Although spontaneous blinking is one of the most frequent human movements, little is known about its neural basis. We developed a rat model of spontaneous blinking to identify and better characterize the spontaneous blink generator. We monitored spontaneous blinking for 55 min periods in normal conditions and after the induction of mild dry eye or(More)
The ability to taste 6-n-propylthiouracil (PROP) as bitter is determined genetically. The present study investigated whether this genetic ability was correlated with alcoholism and/or depression. Four groups of community college students (n = 25 each) were constituted based on the presence or absence of alcoholism and/or depression in themselves or their(More)
Pelchat and Danowski found a significantly higher proportion of nontasters of 6-n-propylthiouracil (PROP) among children of alcoholics than among children of nonalcohlics, suggesting a possible genetic association between alcoholism and PROP tasting ability. They suggested that nontasters may not find alcohol as bitter as tasters do and may be at greater(More)