Adrenocortical Functioning in Boys with Attention-Deficit/Hyperactivity Disorder: Examining Subtypes of ADHD and Associated Comorbid Conditions

Disruptions to hypothalamic-pituitary-adrenal (HPA) axis function have been associated with varying forms of psychopathology in children. Studies suggesting children with ADHD have blunted HPA function have been complicated by the prevalence of comorbid diagnoses and heterogeneity of ADHD. The goals of this research were to assess the relations between waking and stress–response salivary cortisol levels and comorbid disruptive behavior (DBD) and anxiety (AnxD) disorders and problems in boys with ADHD, and to examine whether cortisol levels varied across ADHD subtypes. One hundred seventy elementary school-age boys with ADHD provided salivary cortisol at waking and in reaction to venipuncture. Parent reports were used to assess boys’ psychiatric diagnoses and severity of behavioral problems. Boys’ comorbid AnxD and anxiety problems were associated with greater cortisol reactivity, whereas boys’ comorbid DBD and oppositional problems predicted diminished adrenocortical activity. Reactive cortisol increases were greatest in boys with ADHD and comorbid AnxD, but without DBD. ADHD subtypes were not differentially associated with waking, pre-stress baseline, or reactive cortisol levels. However, comorbid DBD predicted decreased cortisol reactivity in boys with inattentive and hyperactive subtypes of ADHD, but not in boys with combined subtype of ADHD. The results clarify previous patterns of distinct and divergent dysregulations of HPA function associated with boys’ varying kinds of psychopathology.

A General Factor of Personality in the Millon Clinical Multiaxial Inventory-III, the Dimensional Assessment of Personality Pathology, and the Personality Assessment Inventory

A General Factor of Personality (GFP) occupies the apex of the hierarchy in three prominent personality disorder inventories. On the Millon Clinical Multiaxial Inventory-III, a GFP accounted for 41% of the variance in two second-order factors, 31% of the variance in five first-order factors, and 26% of the variance in all 24 scales. On the Dimensional Assessment of Personality Pathology, a GFP accounted for 61% of the variance in six first-order factors and 36% of the variance in all 18 scales. In a cross-validation study of the Personality Assessment Inventory, a GFP accounted for 65% of the variance in two second-order factors, 47% of the variance in five first-order factors, and 27% of the variance in all 18 scales.     

Measuring fluid intelligence on a ratio scale: Evidence from nonverbal classification problems and information entropy

Drawing on the g factor and information theory literatures, the relationship between the four subtests of the Culture-Fair Intelligence Test (CFIT) and the entropy of the Ruiz Absolute Scale of Complexity Management (R-ASCM) was investigated. In results based on data collected from 186 university students, the entropy of the R-ASCM mostly loads the first principal component extracted from the CFIT subtests and shows a corresponding strong relationship with the item difficulty of the R-ASCM. Because entropy is a ratio scale of complexity— with a true zero and units called bits—these findings suggest that entropy is the right vehicle for measuring the information contained in nonverbal intelligence tests.     

How to eliminate self-reference: a précis

We provide a systematic recipe for eliminating self-reference from a simple language in which semantic paradoxes (whether purely logical or empirical) can be expressed. We start from a non-quantificational language L which contains a truth predicate and sentence names, and we associate to each sentence F of L an infinite series of translations h ₀(F), h ₁(F), ..., stated in a quantificational language L ^*. Under certain conditions, we show that none of the translations is self-referential, but that any one of them perfectly mirrors the semantic behavior of the original. The result, which can be seen as a generalization of recent work by Yablo (1993, Analysis, 53, 251–252; 2004, Self-reference, CSLI) and Cook (2004, Journal of Symbolic Logic, 69(3), 767–774), shows that under certain conditions self-reference is not essential to any of the semantic phenomena that can be obtained in a simple language.     

The ventromedial hypothalamus and aggressive behaviour in rats

Male rats were given bilateral lesions in either the anterior or posterior ventromedial hypothalamus (VMH). The intermale aggressive behaviour of these animals within their own territory was observed before and after the surgical procedure and compared with the behaviour of sham-operated animals. The effects of anterior VMH lesions include an increased tendency to respond with frontal threatening upon approach of a conspecific male. This behaviour closely resembles the aggressive responses described in “shock-induced aggression” tests. Posterior VMH lesions facilitate territorial aggressive behaviour characterized by approaching the opponent followed by lateral threatening and fighting. It is suggested that 2 distinct neural substrates exist, which serve to inhibit defensive (anterior-VMH) and offensive (posterior-VMH) intermale aggression, respectively.