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M McManis

Publications and source records attributed to M McManis.

3 recordsLinked to original sources

Functional neuroimaging with MEG: normative language profiles.

The reliability of language-specific brain activation profiles was assessed using Magnetoencephalography (MEG) in five experiments involving ninety-seven normal volunteers of both genders ranging in age from seven to eighty-four years. MEG data were analyzed with a fully automated method to eliminate subjective judgments in the process of deriving the activation profiles. Across all experiments, profiles were characterized by significant bilateral activity centered in the superior temporal gyrus, and in activity lateralized to the left middle temporal gyrus. These features were invariant across age, gender, variation in task characteristics, and mode of stimulus presentation. The absolute amount of activation, however, did decline with age in the auditory tasks. Moreover, contrary to the commonly held belief that left hemisphere dominance for language is greater in men than in women, our data revealed an opposite albeit a not consistently significant trend.

Adolescent↗

Temperamental contributions to the affect family of anxiety.

The discovery of pharmacologic interventions that mute the intensity of anxiety and guilt in some individuals has been a benevolent gift to those who suffer from these disabling states. Although some commentators have wondered about the social consequences of large numbers of asymptomatic persons taking these drugs, few have questioned the advantages for the smaller group of anguished patients. It is likely, however, that, during the next century, scientists will discover a drug that eliminates the feeling components of guilt and remorse while leaving intact the semantic knowledge that certain acts are ethically improper. An individual who took this drug regularly would continue to know that deceiving a friend, lying to a client, and stealing from an employer are morally wrong but would be protected from the uncomfortable feeling of guilt or remorse that accompanies a violation of a personal moral standard. It is reasonable to wonder, therefore, whether our society would be changed in a major way if many citizens were protected from guilt and remorse. Most Western philosophers, especially Kant, made reason the bedrock of conscience. People acted properly, Kant believed, because they knew that the behavior was morally right. All individuals wish to regard the self as virtuous and try to avoid the uncertainty that follows detection of the inconsistency that is created when they behave in ways that are not in accord with their view of the self's desirable attributes. Kant believed that, although the moral emotions restrain asocial acts, they were not necessary for the conduct of a moral life. On the other hand, some philosophers, such as Peirce and Dewey, argued that anticipation of anxiety, shame, and guilt motivate a continued loyalty to one's ethical standards. A person who was certain that he or she was protected from these uncomfortable emotions would find it easier to ignore the moral imperatives acquired during childhood and adolescence. It is not obvious that a drug that blocks remorse also will eliminate the mutual social obligations that make a society habitable; nonetheless, a posture of vigilance that is appropriate for--unlike gorillas--humans can hold representations of envy, anger, and dislike toward people they have never met for a very long time. While we wait for future inquiry to resolve this issue, it is useful to acknowledge that a satisfying analysis of this problem will require a deeper appreciation of the differences between the representations of the biological events that are the foundation of an emotion and the representations that define the semantic networks for the concepts good and bad.

Adult↗

Probing affective pictures: attended startle and tone probes.

Reflexive eyeblinks to a startle probe vary with the pleasantness of affective pictures, whereas the corresponding P300 varies with emotional arousal. The impact of attention to the probe on these effects was examined by varying task and probe type. Probes were either nonstartling tones or startling noises presented during affective picture viewing. Half the participants performed a task requiring attention to the probes; the other participants were told to ignore the probes. Blinks to the startle probe varied with picture pleasantness for both task and nontask conditions. In contrast, P300 magnitudes for both startle and tone probes were reduced during emotionally arousing pictures, irrespective of pleasantness, in task and nontask conditions. Further, attending to the startle probe prompted an augmentation of N100 during unpleasant pictures. The data suggest that affective modulation of probe responses reflects obligatory processes in picture perception.

Acoustic Stimulation↗