Evidence of anhedonia and differential reward processing in prefrontal cortex among post-withdrawal patients with prescription opiate dependence.

Anhedonia is an important but understudied element of a neuroadaptive model underlying vulnerability to relapse in opioid dependence. Previous research using fMRI has shown reduced activation to pleasant stimuli in rostral prefrontal cortex among heroin-dependent patients in early recovery. This study evaluated the presence of anhedonia among recently withdrawn prescription opiate dependent patients (PODP) in residential treatment compared to control subjects. Anhedonia was assessed using self-report, affect-modulated startle response (AMSR), and a cue reactivity task during which participant's rostral prefrontal cortex (RPFC) and ventrolateral prefrontal cortex (VLPFC) was monitored with functional near infrared spectroscopy (fNIRS). The cue reactivity task included three distinct categories of natural reward stimuli: highly palatable food, positive social situations, and intimate (non-erotic) interactions. PODP reported greater anhedonia on self-report (Snaith-Hamilton Pleasure Scale), and showed reduced hedonic response to positive stimuli in the AMSR task relative to controls. PODP also exhibited reduced neural activation in bilateral RPFC and left VLPFC in response to food images and reduced left VLPFC in response to images depicting positive social situations relative to controls. No differences were found for emotionally intimate stimuli. When patients were divided into groups based on the Snaith-Hamilton criteria for the presence or absence of anhedonia, patients endorsing anhedonia showed reduced neural responses to images depicting positive social stimuli and food relative to patients who did not endorse anhedonia. Activations were in areas of RPFC that support the retrieval of episodic memories. The results suggest the presence of anhedonia in a subsample of PODP.

Further evidence for unconscious learning: preliminary support for the conditioning of facial EMG to subliminal stimuli.

This study investigated the predictive validity of facial electromyograms (EMGs) in a subliminal conditioning paradigm. Two schematic faces (pleasant; CS- and unpleasant; CS+), were presented to eight right-handed males during supraliminal pre- and postconditioning phases. Subliminal conditioning consisted of 36 energy-masked presentations of each face pairing the CS+ with an aversive shock 800 ms poststimulus. A forced-choice recognition task established that the energy mask effectively precluded conscious recognition of stimuli. For the obicularis oculi and corrugator EMGs, significant face x condition interactions were found at 20-100 ms and 400-792 ms poststimulus. The results demonstrate the existence of an expressive motoric response related to affect operating in response to a learned but unconscious event. Subjects were not aware of a contingency between the CS+ and the US, suggesting emotional contingencies can be unconsciously acquired.

Factors differentiating personality-disordered individuals with and without a history of unipolar mood disorder.

The relationship between mood disorders and personality disorders has been of longstanding interest to clinicians. Despite theoretical reasons to do so, virtually no studies have examined factors that discriminate personality-disordered subjects with a history of mood disorder (PD/HMD) from personality-disordered subjects without a history of mood disorder (PD). This study examined demographic variables, patterns of comorbidity, measures of life functioning, personality traits, and early life experiences differentiating PD/HMD (n = 83) from PD (n = 214). Diagnoses were assigned using structured clinical interviews and a best-estimate procedure. The results suggest that subjects with borderline personality disorder are more likely to have a life history of mood disorder than are subjects with other personality disorders. In addition, PD/HMDs are more likely to receive a diagnosis of anxiety disorder or alcoholism, to have lower Global Assessment of Functioning (GAF) scores, and to have sought treatment than PDs. On self-report measures of personality, PD/HMDs endorse higher levels of trait anxiety and affective lability (e.g., Harm Avoidance, Neuroticism) than do PDs. PD/HMDs are also more likely to report childhood physical and emotional abuse than are PDs, and to describe their parents as using affectionless control. No differences were found between Axis II clusters as a function of mood disorder history. The discussion suggests a potential model in which early environmental stress interacts with constitutional vulnerabilities to put individuals at an increased risk for both mood and anxiety disorders as well as personality disorders.

Repressive coping style and the experience and recall of emotion: a naturalistic study of daily affect.

Research shows that people characterized as repressors display inhibited recall for unpleasant memories. In this study, the relationship between repressive coping style and the recall of affect near the time of the experience was compared to delayed recall. An experience sampling technique was used to collect affect data twice daily for 4 weeks. Repressive coping style was found to be related to low levels of average daily unpleasant affect and lowered delayed recall of unpleasant affect. Unlike repressors, high anxious individuals overestimated unpleasant affect during delayed recall. Repressors did not exhibit isolation of the dominant unpleasant affect from nondominant unpleasant affect in daily reporting. The overall pattern of results suggests that the effect of repressive coping style is to diminish the encoding of all unpleasant affect, whereas trait anxiety appears to promote overestimation in the recall of unpleasant affect.

Life after trauma: personality and daily life experiences of traumatized people.

In this study, we explored differences in personality and daily life experiences of traumatized (n = 26) versus nontraumatized (n = 30) college students. Study participants completed a variety of personality measures as well as a 28-day experience sampling study assessing daily activities, emotions, and physical health. Although not differing on general demographics, traumatized individuals reported more trait anxiety and lower self-esteem than nontraumatized individuals. They scored higher on Neuroticism, were more introverted, and were less emotionally stable than nontraumatized participants. Traumatized individuals also reported more cognitive disturbances, emotional blunting, and interpersonal withdrawal. They did not report being more depressed, but did endorse cognitive styles associated with heightened risk for depression. Earlier age of trauma was associated with more pathological outcomes: lower self-esteem and psychological well-being, more anxiety, more pessimism, and emotional constriction of positive mood. We compare this symptom profile to that of posttraumatic stress disorder.

Localization of polyamine enhancement of protein synthesis to subcellular components of Escherichia coli and Pseudomonas sp. strain Kim.

At 5 mM Mg2+, spermidine stimulation of polyphenylalanine synthesis by cell-free extracts of Escherichia coli was found to be about 30 times greater than that by extracts of Pseudomonas sp. strain Kim, a unique organism which lacks detectable levels of spermidine. By means of reconstitution experiments, the target of spermidine stimulation was localized to the protein fraction of the highspeed supernatant component (S-100) of E. coli and was absent from, or deficient in, the S-100 fraction of Pseudomonas sp. strain Kim. The spermidine stimulation did not appear to be due to the presence in the E. coli S-100 fraction of ribosomal protein S1, elongation factors, or E. coli aminoacyl-tRNA synthetases. The failure to observe spermidine stimulation by the Pseudomonas sp. strain Kim S-100 fraction was also not due to a spermidine-enhanced polyuridylic acid degradation. The synthesis of polyphenylalanine by Pseudomonas sp. strain Kim extracts was stimulated by putrescine and by S-(+)-2-hydroxyputrescine to a greater degree than was synthesis by E. coli extracts. The enhancement by putrescine and by S-(+)-2-hydroxyputrescine with Pseudomonas sp. strain Kim extracts was found to be due to effects on its ribosomes.

Newly discovered polyamine, 2-hydroxyspermidine, in Pseudomonas acidovorans.

A previously unknown hydroxylated polyamine has been recovered from Pseudomonas acidovorans 29. It has been identified as 2-hydroxyspermidine, N4-(3-aminopropyl)-1,4-diaminobutane-2-ol, by its chromatographic behavior, electrophoretic mobility, and reaction with metaperiodate. It can be synthesized enzymatically from 2-hydroxyputrescine by cell-free preparations from Escherichia coli or P. acidovorans 29 which contain propylamine transferase. It is interesting to note that the naturally occurring compound is the 2-hydroxyspermidine and not the 3-hydroxyspermidine, N1-(3-aminopropyl)-1,4-diaminobutane-2-ol, indicating that the propylamine transferase reacts preferentially with the amine distal to the hydroxyl group. A mixture of 2- and 3-hydroxyspermidines and hydroxyspermine was synthesized by reacting acrylonitrile with 2-hydroxyspermidine and catalytic reduction of the products with hydrogen. N-(gamma-aminopropyl)-beta-alanine, used to help identify the hydroxyspermidines, was synthesized from N-(3-aminopropyl)-3-aminopropanenitrile by hydrolysis with 10% NaOH.