Behavioral and neural biology
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Behav. Neural Biol. · Jul 1994
Comparative Study Clinical Trial Controlled Clinical TrialElectrophysiological correlates to cued attentional shifts in the visual and auditory modalities.
Reaction time (RT) is usually speeded and slowed to correctly and incorrectly cued target stimuli, respectively, in experiments on attention shift (Posner, 1988). When targets occur in a spatial location different from the cue, shifting attention from the cued location to the target location involves interrupt of ongoing activity, move attention to the new location, and reengage attention. The present study investigated whether the cognitive operations involved in cued vs uncued attentional shifts also were detectable in the event-related potentials (ERPs). ⋯ The auditory experiment showed P3 enhancement frontally and reduced amplitudes at temporal and parietal leads. No RT differences were seen to Valid and Invalid trials. The existence of an anterior attention system involved in interrupt and disengage of attention, and a posterior attention facilitation system related to cue presentation is discussed.
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Behav. Neural Biol. · Nov 1987
Motor control of the appetitive phase of feeding behavior in Aplysia.
The appetitive phase of feeding behavior, in the gastropod, Aplysia, consists of head lifting, head waving, orientation of the head to food, and locomotion. We have initiated studies of the neural control of head waving using three methods: (i) anatomical description of the nerves innervating muscles that are involved in head movement, (ii) electrical stimulation of nerves in a semi-intact preparation, and (iii) recording from nerves in free-moving animals. The muscles controlling head movements, located in the dorsal and lateral neck region, are innervated primarily by pleural nerve 1 and pedal nerves 2, 3, and 5. ⋯ Cobalt and nickel backfills of pleural nerve 1 and pedal nerve 5 revealed cell bodies in the cerebral, pedal, and pleural ganglia. The neurons are therefore putative motor neurons for the neck muscles involved in appetitive behavior. This evidence suggests that appetitive control of feeding may involve the coordinated activity of several different ganglia.