We provide evidence that the locus coeruleus-norephinephrine (LC-NE) system is the neurophysiological basis of the attentional blink. The attentional blink refers to decreased accuracy for reporting the second of two targets in a rapid serial visual presentation of distractors. The LC-NE account of the attentional blink posits that targets elicit a facilitative LC-NE system response that is ava...

A current theory of attention posits that several micro-indices of attentional vigilance are dependent on activation of the locus coeruleus, a brainstem nucleus that regulates cortical norepinephrine activity (Aston-Jones et al., 1999). This theory may account for many findings in the infant literature, while highlighting important new areas for research and theory on infant attention. We exami...

We have examined the effects of the highly selective alpha 2-adrenoceptor agonist, dexmedetomidine, on noradrenaline release and cell firing in isolated, superfused slices of rat locus coeruleus. Dexmedetomidine decreased both noradrenaline release and cell firing rate in a concentration-dependent fashion, with an EC50 of 3.97 (SEM 0.97) x 10(-9) mol litre-1 for noradrenaline release and 0.92 (...

Many psychophysiologists have noted the striking similarities between the antecedent conditions for the P3 component of the event-related potential and the orienting response: both are typically elicited by salient, unexpected, novel, task-relevant, and other motivationally significant stimuli. Although the close coupling of the P3 and orienting response has been well documented, the neural bas...

Research on cognitive aging has focused on how decline in various cortical and hippocampal regions influence cognition. However, brainstem regions play essential modulatory roles, and new evidence suggests that, among these, the integrity of the locus coeruleus (LC)-norepinephrine (NE) system plays a key role in determining late-life cognitive abilities. The LC is especially vulnerable to toxin...

To characterize the electrophysiological properties of neurons in the medial agranular frontal cortex (Fr2) with respect to arousal level and locus coeruleus (LC) activity, we recorded spontaneous and auditory-evoked single unit activity in these areas simultaneously during different states of arousal in the rat. In the low-arousal state, as determined by EEG, 14/56 Fr2 neurons showed a tonic i...

The nucleus paragigantocellularis (PGI) is located in the rostral ventrolateral medulla and has noticeable connections with some other brain nuclei, such as locus ceruleus, nucleus raphe magnus and periaqueductal gray. In rats it is 3 mm in rostrocaudal and 1 mm in mediolateral and 1 mm in the dorsolateral aspect. Anatomically and functionally, PGI has been divided into two subnuclei, retrofaci...

Single unit recording has been used as a well-known technique to study the electrical behavior of neurons. In this respect, the classical methods are rather expensive. In this study a simple and inexpensive method for single unit recording studies has been introduced. Computer sound card was used for data acquisition. Neural responses were saved via simple sound applicable packages and then ana...