Psychopathic individuals' lack of responsiveness to punishment cues and poor self-regulation have been attributed to fearlessness (D. T. Lykken, 1957, 1982, 1995). Alternatively, deficient response modulation (RM) may hinder the psychopathic individual's processing of peripheral information and self-regulation when they are engaged in goal-directed behavior… (More)
A passive avoidance task was administered to 97 Caucasian and 110 African American offenders to (a) replicate prior research demonstrating poor passive avoidance in psychopathic individuals (Ps) with low anxiety, (b) compare the effects of anxiety, neuroticism, and fear in identifying subgroups of Ps and controls who differ in passive avoidance, and (c)… (More)
Selective attention among offenders with psychopathy was investigated using 3 Stroop paradigms: a standard color-word (CW) Stroop, a picture-word (PW) Stroop, and a color-word Stroop in which the word and color were spatially separated (separated CW). Consistent with "overselective" attention, offenders with psychopathy displayed reduced Stroop interference… (More)
In an eort to validate Levenson, Kiehl (PCL-R) and examined its relation to criminal activity and a passive avoidance task. Participants were 270 Caucasian and 279 African-American participants in a minimum security state prison. Con®rmatory factor analysis provided modest support for the original SRPS factor structure. Although diagnostic concordance of… (More)
Theorists commonly assume that true or primary psychopathic individuals experience little anxiety or neurotic conflict. This study examined the relationship between psychopathy and anxiety in 104 Caucasian and 113 African American incarcerated men using the Psychopathy Checklist--Revised (PCL-R; R. D. Hare, 1991) and multiple self-report measures to tap… (More)
Damasio and colleagues (A. R. Damasio, 1994; A. R. Damasio, D. Tranel, & H. Damasio, 1990) have theorized about a possible relationship between somatic markers and the behavior of psychopathic individuals (Ps), but, to date, there are no published data regarding the proposed relationship. The authors assessed 86 Caucasian and 71 African American male… (More)
This paper is an initial inquiry into the structure of the Hopf algebra of matroids with restriction-contraction coproduct. Using a family of matroids introduced by Crapo in 1965, we show that the subalgebra generated by a single point and a single loop in the dual of this Hopf algebra is free.
We introduce a noncommutative binary operation on matroids, called free product. We show that this operation respects matroid duality, and has the property that, given only the cardinalities, an ordered pair of matroids may be recovered, up to isomorphism, from its free product. We use these results to give a short proof of Welsh's 1969 conjecture, which… (More)