Evoked Responses and Changes During Attentive Factors in Man

Effects of Hypnotic Instructions on P300Event-Related-Potential Amplitudes: Research and Clinical Implications

“…Some have shown reduction in the amplitude of the evoked response during a hypnotic instruction that the stimulus be perceived as attenuated (Clynes, Kohn, & Lifshitz, 1964;Galbraith, Cooper, & London, 1972;Guerrero-Figueroa & Heath, 1964;Hernandez-Peon & Donoso, 1959;Wilson, 1968), but a number of other studies have failed to demonstrate any differences (Amadeo & Yanovski, 1975;Andreassi, Balinsky, Gallichio, DeSimone, & Mellers, 1976;Beck & Barolin, 1965;Beck, Dustman, & Beier, 1966;Halliday & Mason, 1964;Serafetinides, 1968;Zakrzewski & Szelenberger, 1981). Possible explanations for this SPIEGEL AND BARABASZ variation in findings include small sample sizes, the use of patients with severe neurological or psychiatric disorders, semiquantitative analysis of event-related potentials, and hypnotic instructions which require the subject to attend to the stimulus rather than ignore it (e.g., 'the stimulus will appear less bright than usual).…”

Hypnotic hallucination alters evoked potentials.

“…The nature of these controls suggests that they operate much as does a zoom lens in providing a trade-off between a wide-angle view (ambience) and resolution (focus; Marg & Adams, 1970; Pribram, 1966, 1967). Individuals vary in hypnotizability, and there is some evidence that in hypnotizable individuals the amplitude of the evoked response (ERP) is diminished in response to hypnotic suggestion that the stimulus is attenuated (Clynes, Kohn, & Lifshitz, 1964; Galbraith, Cooper, & London, 1972; Guerrero-Figueroa & Heath, 1964; Hernandez-Peon & Donoso, 1959; Wilson, 1968), but others have not confirmed this relation (Amadeo & Yanovski, 1975; Andreassi, Balinsky, Gallichio, De Simone, & Mellers, 1976; Beck & Barolin, 1965; Beck, Dustman, & Beier, 1966; Halliday & Mason, 1964; Serafetinides, 1968; Zakrzewski & Szelenberger, 1981). In contrast to these earlier studies, Barabasz and Lonsdale (1983) recently demonstrated significant amplitude increases rather than decreases of the P300 component of olfactory-evoked potentials among high-hypnotizable subjects experiencing anosmia.…”

Effects of Reaction Time Task Upon Human Visual Evoked Response Under Conditions of Fixed and Variable Foreperiods

“…The evoked responses have also been shown to be influenced by several psychological factors such as stimulus meaning (Begleiter, Gross, & Kissin, 1967;Begleiter & Platz, 1969), and attention directed by counting stimuli (Garcia-Austt, 1963;Garcia-Austt, Bogacz, & V%anzulli, 1964;Jouvet & Courjon, 1958), by sensory discrimination (Davis, 1964;Satterfield, 1965), by reaction time task (Donchin & Lindsley, 1966;Dustman & Beck, 1965;Morrell & Morrel, 1965, and by hypnotic suggestion (Guerrero-Figueroa & Heath, 1964).…”