Prior Sessions Research Articles

Use of gelatin puzzle phantoms to teach medical students isolated ultrasound transducer movements and fundamental concepts

BackgroundPsychomotor skills related to the use of medical ultrasound are a fundamental, but often overlooked component of this ubiquitous medical imaging technology. Although discussions of image production/orientation, sonographic planes, and imaging/scanning techniques are common in existing literature, these discussions rarely address practical skills related to these basic concepts. The cognitive load of transducer movements and machine operation, in conjunction with learning the ultrasound representation of anatomy, may overwhelm a novice learner. Our goal was to develop and evaluate a set of ultrasound puzzle phantoms for students to use as they learn isolated, specific transducer movements and sonographic concepts. We intentionally created phantoms that contain objects that are likely familiar to students to reduce the cognitive load associated with simultaneously learning the ultrasound interpretation of anatomy.MethodsThis preliminary evaluation of our novel, homemade, gelatin ultrasound puzzle phantoms was performed using pretests and posttests obtained by scanning an assessment phantom, and student questionnaires. Two phases of training and testing occurred with feedback from Phase 1 allowing for refinement of the puzzles and techniques for testing. Skills taught and evaluated included probe rotation, depth assessment, sliding, and tilting.ResultsTwenty-eight students attended the Phase 1 training session with positive trends in students’ abilities to use rotation, sliding, and tilting to answer questions, while only depth showed statistically significant improvements (p = 0.021). Overall students agreed the experience a productive use of time (86%), was beneficial (93%), and would recommend to others (93%). Fifteen (54%) students returned 3 months later. There was no significant decay in skills obtained from the prior training session. In Phase 2, 134 medical students participated, and 76 (57%) completed an online questionnaire. A majority of students agreed they had a better understanding of rotation (83%), depth (80%), sliding (88%) and tilting (55%). Similar to Phase 1, many students (75%) felt the experience was beneficial.ConclusionsThis preliminary study gave us insight into student opinions, as well as information to guide future scalability and development of additional ultrasound puzzle phantoms to aid in medical student education of isolated transducer movements and sonographic concepts prior to imaging human anatomy.

Gender Bias in Opinion Aggregation

Gender biases have been documented in areas including hiring, promotion or performance evaluations. Many of these decisions are made by committees. We experimentally investigate whether committee deliberation contributes to gender biases. In our experiments participants perform a real effort task with subjective performance and rate the task performance of other participants. In a 3 $\times$ 2 design we vary the extent to which communication among raters is possible and whether or not the experiment is gender-blind. There is little evidence of gender bias in the absence of communication or with minimal communication. By contrast, gender bias is strong and highly statistically significant under open communication. In the latter case 60 percent of ratings received by men are revised upwards after deliberation compared to only 25 percent of ratings received by women. As a consequence women are ranked on average three positions lower after deliberation. We then test two interventions for open deliberation. Randomizing the order of speaking does not reduce gender bias, but an information intervention where raters are informed of gender bias in prior sessions does.

Safety of Caplacizumab in Patients Without Documented Severe ADAMTS13 Deficiency During the HERCULES Study

Safety of Caplacizumab in Patients Without Documented Severe ADAMTS13 Deficiency During the HERCULES Study

P039: The iterative evaluation and development of a core and high-acuity low-occurrence simulation-based procedures training program for emergency medicine trainees

Introduction: Competency-based skills development has driven the evolution of medical education. Simulation-based education is established as an essential tool to supplement clinical encounters and it provides the opportunity for low-stakes practice of common and high-acuity low-occurrence (HALO) procedures and scenarios. This is particularly important for emergency medicine trainees working to build confidence, knowledge, and skills in the field. Methods: In the procedural training sessions, learners rotate through 6 small-group stations over a 3-hour period. Skills topics are determined from faculty input, prior session feedback, and literature reviews. Topics included chest tubes, airway intervention, lumbar punctures and trauma interventions. Online content and brief written materials are used for pre-session learning. The small groups use hands-on faculty-guided training, with real-time feedback. Printed materials supplement key learning points at the stations. A combination of low-fidelity task trainers and simulated patients are used for practice and demonstration. R3 EM residents have the opportunity to mentor junior learners. Brief participant surveys are distributed at each session to gather qualitative and quantitative feedback. Results: Feedback forms were completed by 79/85 (92.9%) learners over a period of 4 years (2015-2018). Participants included medical students (11.8%), EM residents (52.9%), and non-EM residents (35.3%). 84.8% (67/79) gave positive qualitative feedback on the sessions, citing points such as the beneficial practice opportunities, quality of instruction, and utility of the models. Updated surveys (N = 26) used a 5-point Likert scale (1 = disagree strongly; 5 strongly agree) in addition to qualitative feedback. Participants indicated that sessions were valuable, and informative (M = 4.692, SD = 0.462; M = 4.270, SD = 0.710). They reported increased understanding of procedures discussed, and they were likely to recommend the session (M = 4.301, SD = 0.606; M = 4.808, SD = 0.394). Conclusion: The ongoing evaluation of our mentor guided hands-on low-fidelity and hybrid simulation-based procedural skills sessions facilitates meaningful programmatic changes to best meet the needs of EM learners. Sessions also provide a forum for EM resident mentorship of junior learners. Feedback indicates learners enjoyed the sessions and found this to be an engaging and effective instructional modality.

TF-9 A Medical Humanities Curriculum for Emergency Medicine Residents

Humanities curricula for medical students have been shown to improve observation skills, empathy, wellness, and tolerance of uncertainty. Such attributes are all the more important in residency training; however, formal implementation and evaluation of similar curricula are lacking in graduate medical education (GME), especially in emergency medicine (EM). EM residency training demands excellent observation and communication skills, ability to practice patient-centered care, and development of skills to cope with stress and uncertainty; humanities curricula may therefore be of specific value for EM residents. This multimodal medical humanities curriculum incorporates themes relevant to EM and comprises museum visits, self-instructional modules, and classroom discussions. The goal of this curriculum is to use visual thinking strategies and narrative medicine to enhance resident observation and communication skills, patient-centeredness, empathy, and wellness. Upon curriculum completion, residents will improve their ability to 1) evaluate impact of personal biases and develop a patient-centered, empathetic approach, 2) demonstrate comfort with ambiguity, 3) make and communicate thoughtful and thorough observations, and 4) develop strategies to mitigate burn-out and address challenging situations. This longitudinal curriculum for EM residents in any year of training is to be implemented over 6 months during weekly protected conference time. In session 1, residents will be introduced to visual thinking strategies at a local museum and assigned a “portrait patient” to follow longitudinally during the curriculum. Three subsequent sessions will be small-group discussions using relevant extracts of novels, short stories, and nonfiction articles and residents’ written responses to the readings to focus on themes of 1) the patient experience, 2) medical conundrums and the art of diagnosis, and 3) the role of the physician in disaster settings. An additional classroom session on the clinical gaze and its correlations in visual arts will serve as a point of synthesis for prior sessions. The curriculum will conclude with a case study-based discussion of ethical dilemmas, which will permit residents to synthesize themes from previous sessions and practice consensus-building and communication skills. A pre- and post-course evaluation will use validated scales to assess curriculum impact on empathy (Jefferson Scale of Empathy), patient-centeredness (Patient-Practitioner Orientation Scale), tolerance of ambiguity (Tolerance of Ambiguity Scale) and burnout (Shirom-Melamed Burnout Measure). Residents will also provide written observations of a set of images, which will be scored for complexity and length. The post-survey will include an evaluation of resident satisfaction with the course and free-text response about potential strategies to mitigate burnout that they may have gleaned from this course. Residents’ ability to analyze, interpret, and communicate observations about visual and written data will be assessed via discussion participation and written responses to readings. If demonstrated to be feasible and if shown to have a positive impact on key resident attributes, this portable and adaptable curriculum could serve as a model not only for other EM residency programs, but for other GME specialties.

Self-administration of the synthetic cathinone MDPV enhances reward function via a nicotinic receptor dependent mechanism

Methylenedioxypyrovalerone (MDPV) is an addictive synthetic drug with severe side effects. Previous studies have shown that MDPV has positive reinforcing properties. However, little is known about the effect of MDPV self-administration on the state of the brain reward system and the neuronal mechanisms by which MDPV mediates its effects. The goal of the present studies was to determine the effect of MDPV self-administration on reward function and the role of cholinergic neurotransmission in the reinforcing effects of MDPV. To study the effect of MDPV self-administration on the brain reward system, rats were prepared with intravenous catheters and intracranial self-stimulation electrodes (ICSS). For 10 days, the reward thresholds were assessed immediately before (23 h post prior session) and after 1 h of MDPV self-administration. The reward thresholds were decreased immediately after MDPV self-administration, which is indicative of a potentiation of brain reward function. The reward thresholds 23 h after MDPV intake gradually increased over time, which is indicative of anhedonia. Pretreatment with the nicotinic acetylcholine receptor (nAChR) antagonist mecamylamine decreased the self-administration of MDPV and completely prevented the decrease in reward thresholds. A control study with palatable chocolate pellets showed that responding for a natural reinforcer does not affect the state of the brain reward system. Furthermore, mecamylamine did not affect responding for food pellets. In conclusion, the self-administration of MDPV potentiates reward function and nAChR blockade prevents the reward enhancing effects of MDPV self-administration. Preventing the MDPV-induced increase in cholinergic neurotransmission might be a safe approach to diminish MDPV abuse.

Moderate-intensity exercise boosts the N2 neural inhibition marker: A randomized and counterbalanced ERP study with precisely controlled exercise intensity

A prior session of moderate intensity continuous exercise (MCE) benefits performance during tasks requiring conflict resolution but the specific cognitive process that underlies this improvement remains unknown. Many studies postulate that MCE increases inhibition, but ERP evidence is ambiguous due to significant differences across past procedures. Most importantly, exercise intensity, which modulates the relationship between acute exercise and cognitive processes, might have varied across past ERP studies. Additionally, previous procedures may not have sufficiently engaged the inhibition process during tasks.The aim of this study was to assess the effects of an acute exercise session on behavioral (accuracy, RT) and ERP (N2, P3b) indices of cognitive processes engaged in conflict resolution. Contrary to most previous studies, we determined ventilatory thresholds (VTD) in order to precisely control exercise metabolism. Moreover, to ensure engagement of inhibition we used a flanker task in a version eliciting strong conflict. 18 male adults underwent three testing sessions in a randomized and counterbalanced order: moderate-intensity continuous exercise (MCE), high-intensity interval exercise (HIIE), and seated rest condition. After each session participants performed the flanker task, during which EEG data was collected.Compared with the control condition, exercise between the first (VT1) and the second (VT2) ventilatory threshold (MCE), but not exercise that exceeded VT2 (HIIE), improved performance in the task and increased the N2 component, which is a neural marker of inhibition. The study shows that MCE might directly benefit inhibition and shows the need for more precise measures of exercise intensity in future studies.

Technology Use for Non-Educational Purposes during Library Instruction: Effects on Students Learning and Retention of Information

ABSTRACTThe paper examines the impact of students’ use of technology for extracurricular purposes during instruction sessions and its effects on their learning and retention of information. It also reports on whether attendance at a previous library instruction session provided the students with the advantage of scoring higher in the assessment and whether the use of these technologies in class sessions was disruptive to other students. This study was conducted during the spring and summer of 2017 on students that attended twenty eight one-time library instructions session for three chemistry laboratory courses. Results indicate that students who used any devices to engage in non-educational activities during an instruction session on average earned lower points in the assessment. On average, the students who attended a prior library instruction session scored higher than those who did not. This result is true irrespective of the group the students were in (control or experimental), or if they used their devices for off-task purposes during the class.

Alliance Rupture and Resolution in Dialectical Behavior Therapy for Borderline Personality Disorder.

The aim of this exploratory study was to investigate alliance rupture and resolution processes in the early sessions of a sample of clients who underwent 1 year of standard dialectical behavior therapy (DBT) for borderline personality disorder (BPD). Participants were three recovered and three unrecovered clients drawn from the DBT arm of a randomized controlled trial that compared the clinical and cost-effectiveness of DBT and general psychiatric management. Alliance rupture and resolution processes were coded using the observer-based Rupture Resolution Rating Scale. Unrecovered clients evidenced a higher frequency of withdrawal ruptures than recovered clients. Withdrawal ruptures tended to persist for unrecovered clients despite the degree of resolution in the prior session, unlike for recovered clients, for whom the probability of withdrawal ruptures decreased as the degree of resolution increased. This study suggests that alliance rupture and resolution processes in early treatment differ between recovered and unrecovered clients in DBT for BPD.

Combat-related guilt and the mechanisms of exposure therapy

Exposure therapy (EXP) is one of the most widely used and empirically supported treatments for PTSD; however, some researchers have questioned its efficacy with specific populations and in targeting specific symptoms. One such symptom, guilt, has garnered increased attention in the PTSD treatment literature, as it is associated with worse symptomatology and outcomes. The current study examined cognitive changes in guilt in response to Intensive (3-week) and Standard (17-week) Trauma Management Therapy (TMT), and the potential mechanisms underlying TMT treatment. TMT is an exposure based intervention that does not include an emotional processing component after the imaginal exposure session. A portion of the sample completed measures of guilt. As a result, sample size for these analyses ranged from 39 to 102 and varied by the domain and measure. Of the 102 individuals that completed the PTSD Checklist- Military Version, 42 completed the Trauma Related Guilt Inventory, and 39 completed the Clinician Administered PTSD Scale supplemental guilt items. Participants reported significant reductions in trauma-related guilt symptoms over the course of the TMT interventions. Greater reductions in avoidance and prior session general arousal predicted the reduction of guilt symptoms. Exposure therapy may be effective in reducing trauma-related guilt even in the absence of the emotional processing component of treatment.

Low blood pressure is sustained during subsequent activities of daily living performed after power training in older women.

The present study aimed to examine the effects of a prior session of power training on blood pressure values during tasks that mimic the activities of daily living in hypertensive and normotensive older women. A randomized crossover experimental design was used for this study. Eleven older women (age, 66.1±1.2 years; body mass index, 26.7±4.8 kg/m2; systolic blood pressure, 133.9±23.4 mmHg) were recruited to participate. Volunteers were randomly underwent to a single session of physical exercise equalized by training volume, characterized by 3 sets of 8–10 repetitions in 8 different exercises. However, Power training session was performed at a higher intensity (moderate) than Sham session (rest/very, very easy ). Immediately after the end of the exercise session, subjects were assigned to perform five tasks that mimic the activities of daily living. Hemodynamic parameters were recorded before and immediately after the session of physical exercise, as well as in the end of each of the tasks. Results demonstrated significant elevations in systolic blood pressure and pulse pressure values during the performance of the tasks after the Sham session. However, values were not altered in the power training session. Data of the present study indicate that an acute session of power training can maintain blood pressure values lower during the subsequent performance of tasks that mimic activities of daily living in older women.

Then & Now: Beyond Turnover

Over the years, the management field has had many important contributors to its theoretical development and practical application of major concepts. As a relatively young academic discipline, we have the good fortune to have access to many of those pioneers who are responsible for its foundation, history, and evolution. The “Then and Now&x201D; program actively involves these people and provides a forum to engage with those who are following in their footsteps. “Then and Now&x201D; is an annual symposium that appeals to new and seasoned scholars across the Academy. Prior sessions have centered on goal setting (ft. Locke, Latham & Picollo, 2011), expectancy theory (ft. Vroom & Ellingson, 2012), leadership (ft. Schriesheim, Gardner & Antonakis, 2013), positive OB (ft. Luthans, Welsh & Peterson, 2014) organizational justice (ft. Folger, Bies & Rodell, 2015) and Trust (Sitkin, Gillespie & de Jong, 2016). This year's session focuses on Turnover. The symposium will begin with Tom Lee describing how he became interested in this topic, who collaborated/supported him, early findings, why he continued this research, challenges encountered, and long term outcomes he expected from that early work. Maria Kraimer will talk about her work and how it spans the generations and extends ideas of career shocks into ex/repatriation. The “Now&x201D; panelist Beni Halvorsen will describe how his recent research on client-employee and migrant workers has evolved from the original body of work, and where it is likely to go next. The symposium concludes with audience discussion.

Head impact exposure and time to recovery in youth american football players diagnosed with a concussion

ObjectiveTo compare head impact exposure (HIE) sustained by youth American football players on days of concussion with prior sessions, and to evaluate concussion resolution with objective assessments.DesignProspective,observational study.SettingYouth American football.ParticipantsYouth American football players (11-14 yr, n=57) who had head impact sensors embedded in their helmets; six were diagnosed with a concussion.InterventionsOver four consecutive seasons, baseline and post-injury concussion assessments were performed and HIE was monitored (Head Impact Telemetry system) for all practice/game sessions.Outcome measuresBaseline/Post-concussion assessments – symptoms, balance, reaction time, neurocognitive function (ImPACT), and oculomotor performance (King-Devick). HIE – location, frequency, and magnitude (linear acceleration [LA] and rotational acceleration [RA]).Main resultsFor concussive impacts, the average peak LA was 85.9g(39.7-156.8g) and average peak RA was 6918rad·sec-2(4508-8433rad·sec-2). On average, players sustained 21.3 impacts/session on days of concussion vs. 10.2 in previous sessions. Median LA and RA did not differ on days of concussion when compared to prior sessions (21.9 vs. 20.7g; 1480 vs. 1485 rad·sec-2). Average duration for a concussed player to have his assessment values return to baseline and be cleared for play was 32 days (17-53).ConclusionsConsiderable variation in magnitude existed between impacts that lead to concussion in this population. Players sustained more head impacts in sessions with a concussion compared to prior sessions. Frequency and magnitude of head impacts on the day of concussion did not correlate with time to recovery. Continued observation of a larger cohort is warranted.Competing interestsNone.

The persistence of and resistance to social norms regarding the appropriate amount to Eat: A preliminary investigation

We conducted a preliminary investigation on the resistance to, and persistence of, social influence regarding the appropriate amount to eat, defined in terms of eating an amount similar to that eaten by a confederate. Participants ate pizza both alone and in the presence of remote confederates presenting either a high or low eating norm. In the portion of the experiment examining resistance to social influence, participants given an initial opportunity to form a personal eating norm by eating alone for one session in the absence of social influence were no more resistant to low eating norms than were those who had no such opportunity; however, those who ate alone for two or three prior sessions did show resistance. For the high eating norm, it took three eating alone sessions to create resistance. In the portion of the experiment examining persistence of social influence, when participants ate alone following a session with norm-setting remote confederates, the effect of the social influence persisted. However, the persistence effect varied by norm and weakened over time. Participants modeled a low eating norm for only one additional session and the size of the effect was markedly weaker. By contrast, the high norm persisted for all of the remaining sessions. Thus, individuals’ social influence histories can affect their eating.

Optimizing engagement in goal pursuit with youth with physical disabilities attending life skills and transition programs: an exploratory study

Purpose: Identify strategies youth perceive will optimize their engagement in goal pursuit in life skills and transition programs using an engagement framework involving affective, cognitive, and behavioral components.Methods: A qualitative descriptive design was used. Two semi-structured interviews were conducted with seven youth. The first was informed by a prior observation session, and the second occurred after the program ended and explored youths’ perceptions of whether and how their engagement changed. Data were analyzed using thematic analysis.Results: The analysis generated eight strategies youth considered effective. These were categorized under the three components of engagement. Affective strategies: (1) building a relationship on familiarity and reciprocity; and (2) guiding the program using youths’ preferences and strengths. Cognitive strategies: (3) assisting youth to envision meaningful change; (4) utilizing youths’ learning styles; and (5) promoting awareness of goal progress. Behavioral strategies: (6) ensuring youth access to a resource network; (7) providing youth multiple decision opportunities; and (8) enabling youth to showcase capabilities.Conclusions: Service providers together with youth are encouraged to consider the role of context and self-determination needs in order to optimize youth engagement in goal pursuit. Systematic approaches to studying engagement are necessary to learn how to maximize rehabilitation potential.Implications for RehabilitationService providers are encouraged to be aware of the nature of engagement strategies identified by youth.Comprehensive frameworks of engagement are essential to generate knowledge on the range of strategies service providers can use to engage clients in rehabilitation services.Strategies perceived by youth to optimize their engagement in goal pursuit in life skills and transition programs have subtle yet significant differences with strategies used in other rehabilitation settings like mental health and adult healthcare services.Self-determination theory shows potential in guiding further research on exploring the role of engagement in maximizing rehabilitation outcomes.

Sudden gains in cognitive-behavior therapy for treatment-resistant depression: Processes of change.

Sudden gains were investigated in cognitive-behavioral therapy (CBT) for treatment-resistant depression (TRD). Client and therapist processes in sessions proximal to sudden gains were examined to better understand the antecedents of sudden gains and potential mechanisms linking them to outcome. Participants were 156 adults with TRD in a randomized controlled trial of CBT as an adjunct to pharmacotherapy (Wiles et al., 2013). Depression symptoms were assessed by the Beck Depression Inventory-II at each session. In a subsample of 50 clients, audio-recordings of 125 therapy sessions were rated for hope, emotional processing, and therapist competence in case-conceptualization. Sudden gains were experienced by 54% of participants. Those with gains reported significantly lower depression severity at 12-month follow-up and more remission of symptoms than those without gains. Sudden gains also predicted lower depression at follow-up, beyond the slope of linear change in symptoms across treatment. Therapists demonstrated greater competence in case conceptualization with clients who reported sudden gains, and those with gains expressed more hope in sessions prior to a gain. In addition, more hope and emotional processing in the pregain sessions predicted less depression at follow-up, controlling for depression scores in the prior session. Better therapist conceptualization skills and more client hope in the baseline and pregain sessions were also associated with more emotional processing in those same sessions. This study extends the phenomenon of sudden gains in CBT for depression to a treatment-resistant population and identified important therapy processes that predicted long-term outcomes: hope and emotional processing. (PsycINFO Database Record

Interaction with Shelter Dogs Reduces Negative Affect of Adolescents in Substance Use Disorder Treatment

ABSTRACTWe investigated the effectiveness of a human–animal interaction program, involving dogs from an animal shelter, in improving affect of adolescent males in inpatient treatment for substance use disorder (SUD). We hypothesized that adolescents would experience improvements in affect and attitudes toward activities when participating in human–dog interaction activities (dog-interaction condition) compared with “treatment-as-is” recreational activities (control condition). Participants were assigned to weekly 1-h-long condition activities for 8 weeks (4 weeks per condition). Due to attrition, only the participants’ first and second exposures to each condition were evaluated. Using a withinand between-subjects, repeated measures crossover design, we assessed effects of the two conditions on affective states as indexed by Positive and Negative Affect Scale-Expanded Form (PANAS-X) subscales (mixed linear model, n = 12). Attitudes toward doginteraction and control activities were assessed using a researcher-generated survey (ordered logistic regression, n = 14, mean age = 16.2 years). Condition impacted Hostility (F(1,31) = 6.55, p < 0.05) and Sadness (F(1,41) = 4.62, p < 0.05) subscale scores; scores were higher following the control condition and lower following the dog-interaction condition. There was a carryover effect of condition in the previous activity session on Sadness scores during the current activity session (F(1,41) = 4.32, p < 0.05), suggesting that the prior session experience affected current expectations. In the attitudes survey, the dog-interaction condition elicited more positive responses than the control condition (X2 ≥ 4.10, df = 1, p < 0.05). From this exploratory study, we conclude that the dog-interaction activities induced an improvement in affect, specifically within dimensions of negative affect, and participants had a more favorable attitude toward the dog activities than the treatment-as-is activities. Offering activities involving interaction with shelter dogs thus shows promise as a useful method for restoring responsiveness to naturally reinforcing (non-substance-related) affective stimuli in adolescents with SUD.

Temporal Sequencing of Change in Posttraumatic Cognitions and PTSD Symptom Reduction During Prolonged Exposure Therapy

Prolonged exposure (PE) effectively reduces negative cognitions about self, world, and self-blame associated with posttraumatic stress disorder (PTSD), with changes in posttraumatic cognitions being associated with reductions in PTSD symptoms (Foa & Rauch, 2004). Further, recent research has demonstrated that cognitive change is a likely mechanism for PTSD symptom reduction in PE (Zalta et al., 2014). The present study examines temporal sequencing of change in three domains of posttraumatic cognitions (i.e., negative cognitions about the self, negative cognitions about the world, and self-blame) and PTSD symptoms during the course of PE. Adult outpatients meeting diagnostic criteria for PTSD were recruited at 4 sites. Participants (N=46) received 8 sessions of PE over 4 to 6weeks. PTSD symptoms and posttraumatic cognitions were assessed at pretreatment and Sessions 2, 4, 6, and 8. PTSD symptom severity and negative cognitions about the self and the world each decreased significantly from pre- to posttreatment, while self-blame cognitions were unchanged. Examination of temporal sequencing of changes during the course of PE via time-lagged mixed effects regression modeling revealed that preceding levels of negative cognitions about the world drove successive severity levels of PTSD symptoms, whereas preceding PTSD symptom severity did not drive subsequent negative cognitions about the world. Reductions in negative cognitions about the self led to subsequent improvement in PTSD. Improvement in PTSD symptoms in prior sessions was related to later reduction in negative cognitions about the self, though the impact of negative cognitions in influencing subsequent symptom change demonstrated a stronger effect. Results support that reductions in negative cognitions about the self and world are mechanisms of change in PE, which may have valuable implications for maximizing treatment effectiveness.

The influence of multiple temporal memories in the peak-interval procedure.

Memories for when an event has occurred are used to anticipate future occurrences of the event, but what happens when the event is equally likely to occur at two different times? In this study, one group of rats was always reinforced at 21 s on the peak-interval procedure (21-only group), whereas another group of rats was reinforced at either 8 or 21 s, which varied daily (8-21 group). At the beginning of each session, the behavior of the 8-21 group largely lacked temporal control, but by the end of the session, temporal control was reestablished. When both groups were reinforced at 21 s, the patterns of responding were indistinguishable after subjects in the 8-21 group had experienced 13 reinforcement trials. Finally, the reinforcement times of previous sessions affected the 8-21 group, such that subjects were biased depending on the reinforcement time of the prior session. These results show that when the reinforcement time is initially ambiguous, rats respond in a way that combines their expectations of both possibilities; then they incrementally adjust their responding as they receive more information, but still information from prior sessions biases their initial expectation for the reinforcement time. Combined, these results imply that rats are sensitive to the age of encoded temporal memories in an environment in which the reinforcement time is variable. How these results inform the scalar expectancy theory, the currently accepted model of interval-timing behavior, is discussed.

My Beautiful Hair

Abstract Introduction This is a problem-base-learning (PBL) teaching case intended for first-year medical school human gross anatomy during the course of anatomical dissection and discussion sessio...