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W W Grings

Publications and source records attributed to W W Grings.

10 recordsLinked to original sources
PubMed1986

Brain responses to sine wave modulated light (SML): reliability and relationship to spontaneous EEG.

Brain activity elicited by sine wave modulated light and spontaneous EEGs were obtained from 11 healthy adult males on two separate occasions. Within-subject correlations (test-retest correlation coefficients) for SML responses were high, and comparable to reliability estimates of spontaneous EEG activity in this sample. Reliability of the spontaneous EEG was evaluated using two measures: absolute and relative power. Although their magnitudes were comparable, the test-retest correlation coefficients for the right occipital were consistently higher than those of the left using absolute measures; this pattern was not reflected by test-retest correlations based on relative EEG measures. Finally, the SML responses to 5, 15, 18 and 24 Hz stimulation frequency rates correlated most highly with absolute measures of spontaneous EEG beta, whereas the SML response to 10 Hz stimulation yielded the highest correlations with spontaneous alpha activity.

Adult↗
PubMed1979

Autonomic classical conditioning as a function of awareness of stimulus contingencies.

Two groups of 32 college students were presented compound CSs (lights and tones presented simultaneously) during a classical conditioning paradigm. By means of a masking task and verbal instructions, a partially informed group was made aware of only the visual CS's contingency with the UCS, while a fully informed group was made aware of both the visual and auditory contingencies. Autonomic indices of conditioning (electrodermal responses, heart rate, and digital pulse volume) were later measured to the individual component CSs and to various compound CSs. It was found that: (1) the partially informed group exhibited conditioning exclusively to the visual CS+ and to compounds which included the visual CS+, while (2) the fully informed group exhibited conditioning to both visual and auditory CS+s. The results confirm the importance of awareness in human autonomic discrimination classical conditioning. It is suggested that human autonomic conditioning may be usefully conceptualized as an information processing task with the autonomic indices of conditioning reflecting central cognitive processes.

Acoustic Stimulation↗
PubMed1979

Contingency contrast effects in discrimination conditioning.

Three experiments observed differential electrodermal responding to signal stimuli (CSs) by contrasting positive, random, and negative contingencies between the signals and strong stimuli (UCSs). Experimentation began as a test of the proposition that electrodermal response to a random signal (or CSR) would lie between the response to a reinforced or excitatory stimulus (CS+) and that to a nonreinforced or inhibitory stimulus (CS- or CSI). A clear intermediate position for CSR did not result. Instead it appeared that CSR was operating as a mildly excitatory signal. This led to a second experiment where response to pairs of stimuli with different contingent relations could be compared in independent samples. The pairs were CS+ and CS-, CS+ and CSR, and CSR and CS-. Differential responding was observed in all pairs and response to CSR was significantly larger in the group receiving CSR with CS- than it was in the group receiving CSR with CS+. A contingency contrast effect was suggested. A third experiment explored the implications of a contingency contrast effect by varying overall UCS density, the duration of "safety intervals," and the presence or absence of instructions about contingencies. The UCS density and instruction variables influenced the differential performance to CSR and CS-, a result that was interpreted as further evidence for a perceptual contingency-contrast effect. Some theoretical implications of such a contrast phenomenon are examined, as they apply to autonomic learning. The CS is interpreted as a signal supplying contingency information that is dependent upon a complex of factors in the stimulation environment.

Association Learning↗