Discriminating malingered from genuine civilian posttraumatic stress disorder: a validation of three MMPI-2 Infrequency scales (F, Fp, and Fptsd)

The Infrequency-Posttraumatic Stress Disorder scale (Fptsd), recently created for the Minnesota Multiphasic Personality Inventory-2 (MMPI-2), has demonstrated incremental validity over other MMPI-2 scales in malingered posttraumatic stress disorder (PTSD) detection. Fptsd was developed with combat-exposed PTSD patients, potentially limiting its use with PTSD patients in general. The current study evaluated the MMPI-2's F, Infrequency-Psychopathology scale (Fp), and Fptsd scales in discriminating genuine civilian PTSD among 41 adult victims of child sexual abuse from a group of 39 students instructed to simulate PTSD. Analyses demonstrated Fptsd's incremental validity over F but not over Fp. Based on the two studies examining Fptsd, Fptsd may be more appropriate for combat trauma victims, and Fp may be more appropriate for civilian trauma victims.     

Cross-validation of the MMPI-2 in detecting malingered posttraumatic stress disorder

We attempted to cross-validate findings from a previous study (Elhai, Gold, Sellers, & Dorfman, in press) using a clinical sample of combat-related war veterans to distinguish genuine from malingered posttraumatic stress disorder (PTSD) on the MMPI-2 (Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989). The MMPI-2 scores of 124 male combat war veterans at the PTSD outpatient treatment program of a Veterans Affairs Medical Center were compared with those of 84 adult college students instructed and trained to malinger PTSD. MMPI-2 overreporting variables examined were F, F-Fb, F-K, F(p), Ds2, O-S, OT, and FBS. A stepwise discriminant analysis identified F. F-Fb, F-K, Ds2, O-S, and OT as the best malingering predictors. A predictive discriminant analysis yielded good hit rates for the model with impressive cross-validation results. We assessed cutting scores for the predictors of the model. We discuss clinical implications for using the MMPI-2 to distinguish malingered PTSD from combat-related PTSD.     

Preserved visual lexicosemantics in global aphasia: a right-hemisphere contribution?

Extensive testing of a patient, GP, who encountered large-scale destruction of left-hemisphere (LH) language regions was undertaken in order to address several issues concerning the ability of nonperisylvian areas to extract meaning from printed words. Testing revealed recognition of superordinate boundaries of animals, tools, vegetables, fruit, clothes, and furniture. GP was able to distinguish proper names from other nouns and from nonwords. GP was also able to differentiate words representing living things from those denoting nonliving things. The extent of LH infarct resulting in a global impairment to phonological and syntactic processing suggests LH specificity for these functions but considerable right-hemisphere (RH) participation in visual lexicosemantic processing. The relative preservation of visual lexicosemantic abilities despite severe impairment to all aspects of phonological coding demonstrates the importance of the direct route to the meaning of single printed words.     

The Psychodynamics of the Patient's Active Episodes

The phenomenon of the patient as active change agent is a critically important, but new and understudied one. This paper attempts to explore and to illustrate with clinical examples the psychodynamic foundations of the patient's activity. The concept of an active episode on the part of the patient is introduced and defined. The paper illustrates the ways that active episodes of self-change on the part of the patient can determine the outcome of psychoanalytic therapy.     

Epinephrine fails to enhance performance of food-deprived rats on a delayed spontaneous alternation task

Increases in blood glucose levels after epinephrine injection appear to contribute to the hormone's effects on learning and memory. The present experiment evaluated whether epinephrine-induced enhancement of spontaneous alternation performance would be attenuated in fasted rats that had blunted increases in circulating glucose levels after injections of epinephrine. Rats deprived of food for 24 h prior to injection of epinephrine exhibited significant attenuation of the increase in blood glucose levels seen in fed rats. When the rats were tested on a delayed spontaneous alternation task, epinephrine enhanced performance in fed rats but not in rats deprived of food for 24 h. These findings are consistent with the view that hyperglycemia subsequent to epinephrine injections contributes to the memory-enhancing effects of epinephrine.     

Impaired visual and odor recognition memory span in patients with hippocampal lesions

In a recent study, rats with hippocampal lesions performed as well as did unoperated rats on an olfactory memory span task, performing ~80% correct even when the span length reached 24 odors. This finding seems potentially at odds with demonstrations that memory-impaired patients typically fail tasks in which large amounts of information must be retained. Accordingly, we have assessed recognition memory span performance for line drawings of objects, designs, and odors in amnesic patients with damage thought to be limited to the hippocampal region. The patients were impaired on all three tasks. We consider possible explanations for the difference between the findings for humans and rats, including the fact that olfactory function is particularly well-developed in rodents.     

Acetylcholine modulation of neural systems involved in learning and memory

Extensive evidence supports the view that cholinergic mechanisms modulate learning and memory formation. This paper reviews evidence for cholinergic regulation of multiple memory systems, noting that manipulations of cholinergic functions in many neural systems can enhance or impair memory for tasks generally associated with those neural systems. While parallel memory systems can be identified by combining lesions with carefully crafted tasks, most—if not all—tasks require the combinatorial participation of multiple neural systems. This paper offers the hypothesis that the magnitude of acetylcholine (ACh) release in different neural systems may regulate the relative contributions of these systems to learning. Recent studies of ACh release, obtained with in vivo microdialysis samples during training, together with direct injections of cholinergic drugs into different neural systems, provide evidence that release of ACh is important in engaging these systems during learning, and that the extent to which the systems are engaged is associated with individual differences in learning and memory.     

Adolescents' emotion expectancies regarding aggressive and nonaggressive events: connections with behavior problems

A total of 50 behaviorally disruptive (conduct-disordered or oppositional defiant-disordered) adolescents and 50 comparison adolescents assessed how they expected to feel following both aggressive and nonaggressive situations. Compared with their peers, behaviorally disruptive adolescents expected fewer normative emotions and exhibited somewhat more of an anger emphasis in their nonaggressive emotion attributions, and they expected to feel happier following acts of instrumental/proactive aggression. These patterns of emotion expectancies were linked more closely with teacher ratings of adolescents' proactive aggression than with ratings of reactive aggression. Regression analyses indicated that both nonaggression emotion expectancies and proactive aggression happiness made independent contributions to predicting adolescents' externalizing tendencies. Discussion focused on the contributions of different types of self-attributed emotion expectancies to adolescents' social understanding and behavior.     

The neural circuitry supporting goal maintenance during cognitive control: a comparison of expectancy AX-CPT and dot probe expectancy paradigms

Goal maintenance is an aspect of cognitive control that has been identified as critical for understanding psychopathology according to criteria of the NIMH-sponsored CNTRICS (Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia) and Research Domain Criteria (RDoC) initiatives. CNTRICS proposed the expectancy AX-CPT, and its visual-spatial parallel the dot probe expectancy (DPX), as valid measures of the cognitive and neural processes thought to be relevant for goal maintenance. The goal of this study was to specifically examine the functional neural correlates and connectivity patterns of both goal maintenance tasks in the same subset of subjects to further validate their neural construct validity and clarify our understanding of the nature and function of the neural circuitry engaged by the tasks. Twenty-six healthy control subjects performed both the letter (AX) and dot pattern (DPX) variants of the CPT during fMRI. Behavioral performance was similar between tasks. The 2 tasks engaged the same brain networks including dorsolateral prefrontal cortex (DLPFC) and dorsal parietal regions, supporting their validity as complementary measures of the goal maintenance construct. Interestingly there was greater engagement of the frontal opercular insula region during the expectancy AX-CPT (letter) and greater functional connectivity between the PFC and medial temporal lobe in the DPX (dot pattern). These differences are consistent with differential recruitment of phonological and visual-spatial processes by the two tasks and suggest that additional long-term memory systems may be engaged by the dot probe version.