Chronic perchlorate exposure impairs stickleback reproductive behaviour and swimming performance

We describe behavioural changes in two generations of threespine stickleback (Gasterosteus aculeatus) exposed to environmentally relevant concentrations of perchlorate. The first generation (G(0,2002)) was exposed as two-year-old adults to perchlorate in experimental groups ranging in concentration from less than the method detection limit (<1.1 ppb) to 18.6 ppm for up to 22 days during their courtship, spawning, egg guarding, and first five days of fry guarding. No differences were noted in the behaviour or reproductive output of these fish that were exposed as adults. However, perchlorate exposure throughout development caused widespread effects in the second generation (G(1,2003)), which was spawned and raised through sexual maturity in one of four nominal experimental groups (0, 30 and 100 ppm, and a 'variable' treatment that progressively increased from <1.1 ppb to approximately 60 ppm perchlorate). Dose-dependent effects were found during the G(1,2003)'s swimming and behavioural evaluations, including higher mortality rates among treated fish following stressful events. Perchlorate-exposed fish had higher failure rates during swimming trials and failed at lower flow rates than control fish. A number of treated fish exhibited seizures. Progressively fewer males completed benchmark metrics, such as nest building, spawning, nursery formation, or fry production, in a dose-dependent manner. Fewer males from higher treatments courted females, and those that did initiated courtship later and had a reduced behavioural repertoire compared to fish from lower treatments. The lowest observed adverse effect level (LOAEL) for swimming performance, reproductive behaviour, survivorship and recruitment was 30 ppm perchlorate (our lowest G(1,2003) treatment), and near complete inhibition of reproductive activity was noted among males raised in 100 ppm perchlorate. A small number of treated G(1,2003) females were isolated in aquaria, and some performed reproductive behaviour typical of males, such as biting, leading and zig-zagging in the presence of gravid females. These findings have profound implications for recruitment in wild fish populations exposed to perchlorate, and suggest that perchlorate may disrupt behaviour in other vertebrates as well.     

Operationalizing the Reciprocal Engagement Model of Genetic Counseling Practice: a Framework for the Scalable Delivery of Genomic Counseling and Testing

With the advent of widespread genomic testing for diagnostic indications and disease risk assessment, there is increased need to optimize genetic counseling services to support the scalable delivery of precision medicine. Here, we describe how we operationalized the reciprocal engagement model of genetic counseling practice to develop a framework of counseling components and strategies for the delivery of genomic results. This framework was constructed based upon qualitative research with patients receiving genomic counseling following online receipt of potentially actionable complex disease and pharmacogenomics reports. Consultation with a transdisciplinary group of investigators, including practicing genetic counselors, was sought to ensure broad scope and applicability of these strategies for use with any large-scale genomic testing effort. We preserve the provision of pre-test education and informed consent as established in Mendelian/single-gene disease genetic counseling practice. Following receipt of genomic results, patients are afforded the opportunity to tailor the counseling agenda by selecting the specific test results they wish to discuss, specifying questions for discussion, and indicating their preference for counseling modality. The genetic counselor uses these patient preferences to set the genomic counseling session and to personalize result communication and risk reduction recommendations. Tailored visual aids and result summary reports divide areas of risk (genetic variant, family history, lifestyle) for each disease to facilitate discussion of multiple disease risks. Post-counseling, session summary reports are actively routed to both the patient and their physician team to encourage review and follow-up. Given the breadth of genomic information potentially resulting from genomic testing, this framework is put forth as a starting point to meet the need for scalable genetic counseling services in the delivery of precision medicine.     

Value-based decision-making battery: A Bayesian adaptive approach to assess impulsive and risky behavior

Using simple mathematical models of choice behavior, we present a Bayesian adaptive algorithm to assess measures of impulsive and risky decision making. Practically, these measures are characterized by discounting rates and are used to classify individuals or population groups, to distinguish unhealthy behavior, and to predict developmental courses. However, a constant demand for improved tools to assess these constructs remains unanswered. The algorithm is based on trial-by-trial observations. At each step, a choice is made between immediate (certain) and delayed (risky) options. Then the current parameter estimates are updated by the likelihood of observing the choice, and the next offers are provided from the indifference point, so that they will acquire the most informative data based on the current parameter estimates. The procedure continues for a certain number of trials in order to reach a stable estimation. The algorithm is discussed in detail for the delay discounting case, and results from decision making under risk for gains, losses, and mixed prospects are also provided. Simulated experiments using prescribed parameter values were performed to justify the algorithm in terms of the reproducibility of its parameters for individual assessments, and to test the reliability of the estimation procedure in a group-level analysis. The algorithm was implemented as an experimental battery to measure temporal and probability discounting rates together with loss aversion, and was tested on a healthy participant sample.     

“Not Tied Up Neatly with a Bow”: Professionals’ Challenging Cases in Informed Consent for Genomic Sequencing

As the use of genomic technology has expanded in research and clinical settings, issues surrounding informed consent for genome and exome sequencing have surfaced. Despite the importance of informed consent, little is known about the specific challenges that professionals encounter when consenting patients or research participants for genomic sequencing. We interviewed 29 genetic counselors and research coordinators with considerable experience obtaining informed consent for genomic sequencing to understand their experiences and perspectives. As part of this interview, 24 interviewees discussed an informed consent case they found particularly memorable or challenging. We analyzed these case examples to determine the primary issue or challenge represented by each case. Challenges fell into two domains: participant understanding, and facilitating decisions about testing or research participation. Challenges related to participant understanding included varying levels of general and genomic literacy, difficulty managing participant expectations, and contextual factors that impeded participant understanding. Challenges related to facilitating decision-making included complicated family dynamics such as disagreement or coercion, situations in which it was unclear whether sequencing research would be a good use of participant time or resources, and situations in which the professional experienced disagreement or discomfort with participant decisions. The issues highlighted in these case examples are instructive in preparing genetics professionals to obtain informed consent for genomic sequencing.     

Balancing Genetics (Science) and Counseling (Art) in Prenatal Chromosomal Microarray Testing

Genetic counselors frequently are called upon to assist patients in understanding the implications of prenatal testing information for their pregnancies and their family’s lives. The introduction of highly sensitive testing such as chromosomal microarray has generated additional kinds of uncertainty into the prenatal period. Counselors may feel uncomfortable or inadequately prepared to engage in discussions with prospective parents who are faced with making critical, and timely, decisions about a pregnancy based on uncertain information. As highly sensitive prenatal testing becomes routine in prenatal care, counselors may be in search of approaches to prenatal counseling, as well as specific skills to approach, engage with, and help families find resolution in such challenging circumstances. To assist genetic counselors, we describe practice skills and provide language for approaching conversations with prospective parents. When clinicians regularly provide care to patients and families making life-altering decisions under conditions of significant uncertainty, discomfort is common and compassion fatigue is likely. We make recommendations directly to the genetic counselor working in reproductive and perinatal settings to enhance training and self-care and to decrease discomfort in balancing the scientific- and art- demands of genetic counseling.     

Cognitive resource limitations during sentence comprehension in Parkinson's disease

We report a single-case study of peripherally acquired dyslexia that meets the clinical criteria of "alexia without agraphia." The patient, AA, has a large infarct involving the left posterior cerebral artery. The most striking feature is a severe impairment in recognizing single visually presented letters that precludes explicit or implicit access to reading, even in a letter-by-letter fashion. AA can, however, differentiate letters from similar nonsense characters and digits, and he is also able to identify alphanumeric signs when the visual channel is bypassed (through somesthesic or kinesthesic presentation). Spelling tasks are also well performed. Since there is a breakdown in mapping a visually presented letter to its abstract graphemic representation, we propose the term "visuographemic alexia" for this kind of reading disorder. The pattern of deficits is interpreted following theoretical models previously developed in cognitive neuropsychology. An alexia for arabic numerals with preserved comprehension lends additional support for the crucial processing of different notational systems (e.g., phonographic vs logographic). More general perceptive disorders do not seem to account for these patterns; they are material-specific. Finally, we attempt to specify functional correlations with the implied neural networks.     

Billing and Record-Keeping for Familial Cancer Risk Counseling: A National Survey

We surveyed 111 genetic counselors providing cancer risk counseling (CRC) in order to document their billing and record-keeping practices. Of the 75 respondents, billing was generally done under the supervising physician with a wide variation in charges. Follow-up telephone interviews with 28 counselors who charge patients revealed that billing was usually done using the CPT codes for consultations, and the ICD-9 diagnostic codes for cancer (if applicable), a medical complaint, or a family history of cancer code. Most counselors exclude some clinical information from the patient's medical record. In consultation notes, 81% of counselors document a discussion of genetic testing, but only 37% document the patient's actual testing decision, and only 19% document test results. In anticipation of increased referrals for CRC, data are needed on the components of a CRC visit, the amount of time required to provide CRC, patient outcomes measures, and charges and reimbursement. The feasibility and advisability of keeping results separate from the patient's medical record also needs to be addressed.     

A rule-based categorization deficit in Alzheimer's disease?

This study examined the categorization processes that Alzheimer's disease (AD) patients use during assessments of semantic memory. Rule-based categorization involves the careful, analytic processing of strict criteria to determine category membership, particularly for items from graded categories with ambiguous category membership; similarity-based categorization requires an overall comparison of a test stimulus with a prototype or remembered exemplar of the category and is relatively effective for the rapid categorization of items with unambiguous category membership. To assess these processes in AD, patients were asked to decide the category membership of test stimuli for categories with poorly defined or fuzzy boundaries (e.g., VEGETABLE) and for categories with well-defined boundaries (e.g., FEMALE) and then to judge the representativeness of the test stimulus for its chosen category. A subgroup of AD patients demonstrated a typical pattern of impaired semantic memory compared to healthy control subjects; that is, difficulty deciding the category membership of test items from fuzzy categories. Among these patients, we found no deficit in category membership decisions about items taken from well-defined categories. We also found that AD patients and healthy controls do not differ in their representativeness judgments of items within a correctly judged category. These findings are most consistent with the hypothesis that rule-based categorization difficulty limits semantic memory in AD.     

The Auction Value of Certain Risky Situations

This study evaluated the characteristics of emergent leaders of problem-solving groups with use of semantic differential scales. Subjects were 64 American university undergraduates. Each subject rated all subjects in his group, self included, at each of five sessions. Persons selected as leaders were found by a Q factor analytic technique to cluster on the basis of the following common characteristics: higher than nonleaders in giving directions, formulating goals, and being self-assured; lower than nonleaders in being more quarrelsome and less sensible.

The qualities characteristic of emergent leaders are assigned to them early, remain relatively consistent, and seem independent of personality characteristics. Whether they can be taught to participants who will subsequently be perceived as leaders is currently under investigation.