Schizophrenic subjects show aberrant fMRI activation of dorsolateral prefrontal cortex and basal ganglia during working memory performance.

BACKGROUND: Working memory (WM) deficits in schizophrenia have been associated with dorsolateral prefrontal cortex (DLPFC) dysfunction in neuroimaging studies. We previously found increased DLPFC activation in schizophrenic versus normal subjects during WM performance (Manoach et al 1999b). We now have investigated whether schizophrenic subjects recruit different brain regions, particularly the basal ganglia and thalamus, components of frontostriatal circuitry thought to mediate WM. METHODS: We examined regional brain activation in nine normal and nine schizophrenic subjects during WM performance using functional magnetic resonance imaging. Subjects performed a modified version of the Sternberg Item Recognition Paradigm that included a monetary reward for correct responses. We compared high and low WM load conditions to each other and to a non-WM baseline condition. We examined activation in both individual subjects and averaged group data. RESULTS: Relative to normal subjects, schizophrenic subjects exhibited deficient WM performance, at least an equal magnitude of right DLPFC activation, significantly greater left DLPFC activation, and increased spatial heterogeneity of DLPFC activation. Furthermore, only the schizophrenic group activated the basal ganglia and thalamus, even when matched for task performance with the normal group. CONCLUSIONS: Aberrant WM performance and brain activation in schizophrenia may reflect dysfunction of frontostriatal circuitry that subserves WM. Future studies will elucidate the contribution of the anatomical components of this circuitry to WM deficits.

Academic manpower survey of 1990: II. Kinetics in the United States (from the Joint Task Force on Pathology Manpower ASCP/CAP/APC).

Survey data obtained from chairmen of United States departments of pathology shows a continued shortage of faculty, especially those with the MD or MD/PhD degree. Losses of such faculty by responding departments during the 12 months prior to the survey were distributed as follows: retirement, 40 (15.6% of total); disability/death, 19 (7.4%); termination, 23 (8.9%); resignation, 172 (69.3%); and other, 3 (1.2%). Resignations were due primarily to decisions to join another university (41.4%) or to enter private practice (42.5%); a small proportion were due to individuals who left academe for a pathology position in government or industry, or left both academe and pathology for another field. Comparison with a similar survey performed in 1984 suggests that the manpower situation in academic pathology is worsening, especially with respect to physician faculty. An assessment of those factors known to influence manpower kinetics suggests that it will continue to deteriorate for the foreseeable future with an adverse impact on all sectors of pathology.

Academic manpower survey of 1990: I. Descriptors of departments of pathology in the United States (from the Joint Task Force on Pathology Manpower ASCP/CAP/APC).

A survey of chairmen of United States departments of pathology (97% response rate) augmented with data from the Association of American Medical Colleges shows that roughly two thirds (65%) of departmental faculty are physicians, the great majority of whom are pathologists. Most of the remainder are persons with solely the PhD degree (26.4% of faculty). The composition of departments of pathology in terms of age, gender, ethnic origin, academic rank, and tenure status is also reported. In contrast to a comparable survey performed 5 years previously, the present report shows that in 1989, departments of pathology contained (1) 20.6% more faculty positions, (2) a greater proportion of faculty members with a PhD degree, (3) greater numbers of open positions, and (4) a probable increase in the proportion of faculty that are female and that are of an ethnic minority.

National Pathology Manpower Survey of 1988. Manpower needs in community hospitals and private laboratory practice.

The survey of manpower in community hospital and private laboratory practice of pathology of 1988 presented herein verifies the conclusions of the 1986 survey that a growing deficit of manpower in this sphere of practice is highly likely in the next few years. It appears that the deficit will be even larger than that predicted by the 1986 survey. Steps are urgently needed to increase the flow of graduating medical students, especially those of top quality, into our specialty.

Some characteristics of the community practice of pathology in the United States. National Manpower Survey of 1987.

An evaluation of 629 pathologists engaged in community hospital and private laboratory practice and representing 601 pathology practices of varying size shows surprising uniformity in the distribution of professional effort. On average, pathologists in community practice distribute their effort as follows: surgical pathology, 34.6%; autopsy pathology, 6.7%; cytology, 8.8%; clinical pathology, 18.0%; teaching, 6.0%; research and development, 2.3%; laboratory administration, 17.5%; hospital administration, 2.9%; and other, 3.2%. The average community pathologist is male, 52 years of age, and a graduate of an American medical school (60%). When surveyed in 1986, community pathologists worked an average of 50 hours per week and retired at an average age of 62 years.

Special report--National Manpower Survey of 1987. Manpower needs in community hospital and private laboratory practice of pathology.

A new survey of manpower requirements in the community hospital and private laboratory practice of pathology has been completed and analyzed. The survey used a new instrument, the National Pathology Manpower Database, which will be useful in conducting longitudinal surveys. This instrument will permit organized pathology to monitor changes in pathology manpower needs in the years ahead, which are likely to be fraught with change. The results of this survey foretell a significant deficit of pathologists in community hospital and private laboratory practice within the next five years.

Some characteristics of academic departments of pathology in the United States. Implications for training of academic pathologists.

Data concerning the activities of faculty and various characteristics of academic departments of pathology were obtained from questionnaires returned by 94 chairmen and 1571 faculty members. Data concerning manpower that was the subject of a previous report indicated that the projected supply of MD pathologists for faculty positions was significantly less than the anticipated demand. This article describes the characteristics of academic departments, particularly the activities of faculty that have bearing on the training and expectations of pathologists who are seeking faculty positions.

The responsible use of the clinical laboratory.

Concern about spiralling health care costs is leading to a reexamination of the use of the clinical laboratory and other diagnostic technologies in patient care. Laboratory resources are viewed as limited and their use must be measured to meet real needs. Several observers have noted significant overutilization and inappropriate utilization of laboratory services by patient care physicians, especially at teaching hospitals. Efforts to modify physician behavior by use of educational programs, positive incentives and similar means have been largely disappointing. Several laboratory-based initiatives aimed at bringing about more responsible use of the laboratory are discussed. Improved education in the judicious use of the laboratory, beginning in medical school and carrying on through the early stages of a physician's career, is considered the most promising long-term approach. This, along with improved communication between the laboratory and the clinic, is the avenue most likely to bring about more responsible use of the clinical laboratory in health care.

Manpower needs and supply in academic pathology.

A survey of manpower supply and need in academic pathology departments was conducted by the Joint Task Force on Pathology Manpower of the College of American Pathologists, the American Society of Clinical Pathologists, and the Association of Pathology Chairmen by means of questionnaires distributed to chairmen and faculty of all departments of pathology and laboratory medicine in the United States. Of the 136 departments, responses were obtained from 131 (96%) chairmen and from 1,561 (45%) faculty members. The current total need for faculty members (funded vacant positions) is 272, and the projected aggregate need over the next five years is 693 members for new and replacement positions. The greatest needs are for research MD pathologists and surgical pathologists, followed by autopsy and chemical pathologists. Based on the estimate of current pathology trainees planning academic careers, there is a strong indication that the projected supply of MD pathologists is significantly less than the anticipated demand.

Manpower supply and demand in pathology.

Recently physicians, the federal government, and medical specialty societies have shown increasing interest in manpower needs in medicine and in the medical specialties. Since 1976 the Joint Task Force on Pathology Manpower of the American Society of Clinical Pathologists, the College of American Pathologists, and the Association of Pathology Chairmen has completed and published three reports on pathology manpower supply and demand. The results of these studies agree with a recently completed study by a federally mandated commission. These studies show pathology manpower in the early 1980s is in good balance between supply and demand. They also indicate this equilibrium will continue until 1990 unless unanticipated changes in supply and demand take place.

Third report of the ASCP/CAP/APC joint task force on pathology manpower.

This report concerns the results of pathology manpower surveys encompassing responses from four groups of pathologists: (1) solo and group practitioners; (2) training program directors; (3) house staff; (4) diplomates seeking positions. The rate of response by all four groups is judged highly satisfactory. The results show an approximate balance between supply and demand with respect to manpower in pathology. Comparison with the results of two similar surveys conducted by the Joint Task Force shows the following trends: (1) a continued marked reduction of foreign medical graduate (FMG) trainees; (2) continued increase in the proportion of women entering pathology; (3) an increase in the size of the average practice and a corresponding decrease in the proportion of pathologists in solo practice; (4) a decreased tendency of practicing pathologists to relocate; (5) an increase in pathologists lost to the profession because of death, disability and retirement; (6) a slight decrease (approximately 50) in the number of funded full-time positions and a slight increase in the number of part-time vacancies.

The use of the differential leukocyte count for inpatient casefinding.

The differential leukocyte count is a nonspecific, imprecise, error-prone, usually labor-intensive, and expensive test to perform. Although the differential count is frequently ordered in the absence of clinical suspicion in both inpatient and outpatient settings, its effectiveness as a screening test has been studied little. From a detailed chart review of 287 cases randomly drawn from a population of 2682 adult patients for whom a differential count was performed on admission, we found that 23 per cent of the cases met criteria for admission screening, that abnormal results were found in approximately one half of these screening differential examinations, and that one third of the abnormal examinations were acknowledged in the medical record by a physician. In no instance did a screening differential count appear to have had clinical significance. It may be medically prudent to consider discontinuing the differential leukocyte count as an inpatient screening test for adults.

The manpower situation in pathology: implications for the future.

With the exception of academic pathology and specific subspecialty areas, manpower in pathology is currently in a state of apparent equilibrium between supply and demand. Exogenous influences, and especially an influx of Americans who have attended foreign-chartered medical schools, could disturb this apparent equilibrium. Other key manpower issues with respect to pathology include mechanisms to determine optimal numbers of pathologists, the future productivity of pathologists, current and prospective needs in academic pathology and subspecialty areas, and the role of the federal government in the area of medical manpower. Recommendations to deal with these and related issues are presented.