Thomas Swales - Academia.edu (original) (raw)

Papers by Thomas Swales

Research paper thumbnail of Characterization of smooth pursuit performance in adolescent schizophrenics

Schizophrenia Research

cuitry to create a population of "memory cells", in this model maintenance of memory representati... more cuitry to create a population of "memory cells", in this model maintenance of memory representations is an emergent property from an interaction between the circuit architecture and the input dynamics.

Research paper thumbnail of Neuropsychological functioning in adolescent schizophrenia

Schizophrenia Research

Siblings and offspring of persons with schizophrenia carry elevated genetic risk for the illness ... more Siblings and offspring of persons with schizophrenia carry elevated genetic risk for the illness and manifest attentional and memory impairments. Because less is known about other neuropsychological functions and their specificity in adolescents, we conducted a genetic high-risk (HR) study ...

Research paper thumbnail of A magnetic resonance imaging study of thalamic area in adolescent patients with either schizophrenia or bipolar disorder as compared to healthy controls

Psychiatry Research: Neuroimaging, 1999

The purpose of this study was to compare thalamic size in adolescent patients with either schizop... more The purpose of this study was to compare thalamic size in adolescent patients with either schizophrenia or bipolar disorder and healthy controls. T2-weighted axial magnetic resonance images were used to manually define the area of the thalamus for 20 schizophrenia patients, 15 bipolar patients and 16 normal control subjects, all of whom were adolescents. Two orthogonal planned contrasts were tested: Contrast 1, patients with schizophrenia vs. patients with bipolar disorder; and Contrast 2, both patient groups taken as a single group compared to controls. Contrast 1 was not statistically significant for right or left thalamic area. Contrast 2 was statistically significant and indicated reductions in thalamic area in the patients as compared to controls. The same pattern of results emerged after adjustment for total brain volume. Our results indicate that thalamic abnormalities reported in adult schizophrenic and bipolar patients are also observed in adolescent patients. Our findings also add to the evidence implicating the thalamus in the pathophysiology of schizophrenia and bipolar disorder. ᮊ

Research paper thumbnail of Structural MRI and neuropsychological assessments in adolescent patients with either schizophrenia or affective disorders

Schizophrenia Research, 1996

Research paper thumbnail of Both schizophrenic and bipolar adolescents differ from controls on MRI measures

Schizophrenia Research, 1998

Research paper thumbnail of Medicare hospital utilization increasing for schizophrenia

Schizophrenia Research, 1997

The prevalence, geographic variation and charges to Medicare of hospitalizations among disabled a... more The prevalence, geographic variation and charges to Medicare of hospitalizations among disabled and elderly people in the United States diagnosed with schizophren ia was investigated . Data was obtained from the HCFA 's Medicare inpatient claims files database for all Medicare Part A beneficiaries and 1990 census data. Two studies were conducted. First, a 6 year cross-sectional study examined the frequency of total annual admissions for patients diagnosed with schizophrenia from 1984 to 1989. The number of patients hospitalized with schizophrenia increased 48.6% from 1984 to 1989, and the frequency of total annual admissions increased by 57% from 88,679 in 1984 to 139,354 in 1989. Second, an 8 year prospective cohort study examined hospital utilization from 1984 to 1991. The sample consisted of 57,356 patients with schizophrenia requiring hospitalization during 1984: 72.8% (41,749) were disabled; 27.2% (15,607) were age 65 or older. For the 1984 cohort, there was considerable geographic variation in the prevalence of age-adjusted median rate of re-hospitalizations among patients diagnosed with schizophrenia: Iowa had the highest rate (4.08), and Utah had the lowest (1.95) . The overall length of hospital utilization had a mean of 37.2 days and a median of 12.0 days. Schizophrenia-related hospitalizations among patients on Medicare would appear common, and are producing considerable increases in Medicare expenditures. It is necessary to examine the role of state and federal mental health systems and expenditures in the increasing Medicare fund ing of hospitalizations for patients diagnosed with schizophrenia.

Research paper thumbnail of A study of head size in adult patients with schizophrenia

Schizophrenia Research, 1997

Research paper thumbnail of MRI measurements in adolescents with schizophrenia and bipolar disorder

Schizophrenia Research, 1997

Research paper thumbnail of Six year mortality rates following hospitalization for schizophrenia

Schizophrenia Research, 1997

The prevalence, geographic variation and charges to Medicare of hospitalizations among disabled a... more The prevalence, geographic variation and charges to Medicare of hospitalizations among disabled and elderly people in the United States diagnosed with schizophren ia was investigated . Data was obtained from the HCFA 's Medicare inpatient claims files database for all Medicare Part A beneficiaries and 1990 census data. Two studies were conducted. First, a 6 year cross-sectional study examined the frequency of total annual admissions for patients diagnosed with schizophrenia from 1984 to 1989. The number of patients hospitalized with schizophrenia increased 48.6% from 1984 to 1989, and the frequency of total annual admissions increased by 57% from 88,679 in 1984 to 139,354 in 1989. Second, an 8 year prospective cohort study examined hospital utilization from 1984 to 1991. The sample consisted of 57,356 patients with schizophrenia requiring hospitalization during 1984: 72.8% (41,749) were disabled; 27.2% (15,607) were age 65 or older. For the 1984 cohort, there was considerable geographic variation in the prevalence of age-adjusted median rate of re-hospitalizations among patients diagnosed with schizophrenia: Iowa had the highest rate (4.08), and Utah had the lowest (1.95) . The overall length of hospital utilization had a mean of 37.2 days and a median of 12.0 days. Schizophrenia-related hospitalizations among patients on Medicare would appear common, and are producing considerable increases in Medicare expenditures. It is necessary to examine the role of state and federal mental health systems and expenditures in the increasing Medicare fund ing of hospitalizations for patients diagnosed with schizophrenia.

Research paper thumbnail of Increased presence of white matter hyperintensities in adolescent patients with bipolar disorder

Psychiatry Research: Neuroimaging, 2002

Several reports have noted an increase in white matter hyperintensities (WMH) on MRI scans of adu... more Several reports have noted an increase in white matter hyperintensities (WMH) on MRI scans of adult patients with bipolar disorder. We investigated whether this increase was also evident in a group of adolescent patients with bipolar disorder. The sample consisted of 15 bipolar patients, 19 patients with schizophrenia and 16 healthy comparison subjects. All subjects were adolescents. WMH were blindly rated on T2-weighted and PD-weighted MRI scans using our own scale with documented inter-rater reliability. WMH were present in 10 of 15 bipolar patients (67%), seven of 19 patients with schizophrenia (37%) and five of 16 comparison subjects (31%). The bipolar adolescent group had a statistically significant increased presence of WMH compared both with healthy comparison subjects and the schizophrenic group. The association between WMH and bipolar disorder appears to extend to the adolescent years.

Research paper thumbnail of Hippocampal volume in adolescent schizophrenia

Schizophrenia Research, 1996

Research paper thumbnail of Pediatric Psychology Training: An Analysis of Graduate, Internship, and Postdoctoral Programs

Journal of Pediatric Psychology, 1989

The field of pediatric psychology is in the early stages of formulating its own identity relative... more The field of pediatric psychology is in the early stages of formulating its own identity relative to other areas, such as clinical child and health psychology. This paper complements other recent efforts to delineate training practices and guidelines. Questionnaires regarding doctoral, internship, and postdoctoral training experiences were obtained from 89% of the membership of the Society of Pediatric Psychology. From this information, rankings of the most commonly attended programs at each training level were derived. Some overlap was apparent between doctoral programs that were conducive to training in pediatric and clinical child psychology; however, differences between programs in these areas also were noted. The most commonly attended internship and postdoctoral settings were those in major medical centers or children's hospitals. Suggestions for investigating the current status of predoctoral, internship, and postdoctoral programs that may be facilitative of training in pediatric psychology are discussed.

Research paper thumbnail of Adolescent schizophrenia: A methodologic review of the current neuroimaging and neuropsychologic literature

Journal of Autism and Developmental Disorders, 1995

... Absent Gottschalk & Selin, 12 b Absent Absent 1991 Attention deficit 11 No Conduc... more ... Absent Gottschalk & Selin, 12 b Absent Absent 1991 Attention deficit 11 No Conduct disorder 21 Anxiety disorder 26 Adjustment disorder 20 No Conduct disorder 13 Dysthymic disorder 7Historionic personality 1 Depression (n = 8) No Conduct disorder (n = 2) Borderline (n = 2) ...

Research paper thumbnail of Adolescents With Diabetes: Gender Differences in Psychosocial Functioning and Glycemic Control

Children's Health Care, 1995

... Thomas Swales Case Western Reserve University ... for this possibility in part, we enrolled o... more ... Thomas Swales Case Western Reserve University ... for this possibility in part, we enrolled only adolescents who had diabetes for rnore than 1 year, as residual insulin secretion is typically greatest in the rnonths following the initial diagnosis of IDDM (Clarson, Daneman, Drash ...

Research paper thumbnail of 209. An MRI study of adolescent psychiatric patients and healthy controls

Biological Psychiatry, 1998

Research paper thumbnail of An MRI study of adolescent patients with either schizophrenia or bipolar disorder as compared to healthy control subjects

Biological Psychiatry, 1999

Background: There are few imaging studies in adolescent patients with either schizophrenia or bip... more Background: There are few imaging studies in adolescent patients with either schizophrenia or bipolar disorder. Such studies are of interest because adolescents may have a more severe illness and neurodevelopmental events may have a greater role in their pathophysiology. Methods: We compared 20 patients with schizophrenia and 15 patients with bipolar disorder (10 to 18 years) to 16 normal adolescents on magnetic resonance imaging (MRI) measures of intracranial volume and ventricular and sulcal enlargement. Two planned comparison contrasts were employed, one comparing the two patient groups to each other (contrast 1), and one comparing both patient groups combined to control subjects (contrast 2). Results: None of the contrast 1 comparisons (schizophrenia vs bipolar) were statistically significant. Contrast 2 comparisons (control subjects vs patients) were statistically significant for intracranial volume (reduced in patients) as well as frontal and temporal sulcal size (increased in patients). Conclusions: The patient groups were not statistically significantly different from each other on any measure. The combined patient groups were different from control subjects on intracranial volume and frontal and temporal sulcal size. Also, there was evidence for ventricular enlargement, after removal of a control subject with an extreme value. These findings indicate that the same abnormalities noted in adult populations are present in adolescents. Biol Psychiatry 1999;46:78 -88

Research paper thumbnail of Cognitive Impairment in Adolescents With Schizophrenia

American Journal of Psychiatry, 1997

Objective: The purpose of this study was to determine whether adolescent schizophrenia is charact... more Objective: The purpose of this study was to determine whether adolescent schizophrenia is characterized by neuropsychological deficits. Method: The performance on a battery of neuropsychological tests of 17 adolescents with schizophrenia (mean age=15.71 years) was compared with that of 17 normal adolescents (mean age=15.12 years). Results: Compared with the normal subjects, the patients were impaired on 10 of the 13 measures; larger effect sizes were shown for measures involving working memory and attention than for those involving secondary memory, generative naming, and executive functions. Conclusions: Adolescents with schizophrenia have generalized cognitive dysfunction, which is most apparent on tests of attention and working memory.

Research paper thumbnail of Characterization of smooth pursuit performance in adolescent schizophrenics

Schizophrenia Research

cuitry to create a population of "memory cells", in this model maintenance of memory representati... more cuitry to create a population of "memory cells", in this model maintenance of memory representations is an emergent property from an interaction between the circuit architecture and the input dynamics.

Research paper thumbnail of Neuropsychological functioning in adolescent schizophrenia

Schizophrenia Research

Siblings and offspring of persons with schizophrenia carry elevated genetic risk for the illness ... more Siblings and offspring of persons with schizophrenia carry elevated genetic risk for the illness and manifest attentional and memory impairments. Because less is known about other neuropsychological functions and their specificity in adolescents, we conducted a genetic high-risk (HR) study ...

Research paper thumbnail of A magnetic resonance imaging study of thalamic area in adolescent patients with either schizophrenia or bipolar disorder as compared to healthy controls

Psychiatry Research: Neuroimaging, 1999

The purpose of this study was to compare thalamic size in adolescent patients with either schizop... more The purpose of this study was to compare thalamic size in adolescent patients with either schizophrenia or bipolar disorder and healthy controls. T2-weighted axial magnetic resonance images were used to manually define the area of the thalamus for 20 schizophrenia patients, 15 bipolar patients and 16 normal control subjects, all of whom were adolescents. Two orthogonal planned contrasts were tested: Contrast 1, patients with schizophrenia vs. patients with bipolar disorder; and Contrast 2, both patient groups taken as a single group compared to controls. Contrast 1 was not statistically significant for right or left thalamic area. Contrast 2 was statistically significant and indicated reductions in thalamic area in the patients as compared to controls. The same pattern of results emerged after adjustment for total brain volume. Our results indicate that thalamic abnormalities reported in adult schizophrenic and bipolar patients are also observed in adolescent patients. Our findings also add to the evidence implicating the thalamus in the pathophysiology of schizophrenia and bipolar disorder. ᮊ

Research paper thumbnail of Structural MRI and neuropsychological assessments in adolescent patients with either schizophrenia or affective disorders

Schizophrenia Research, 1996

Research paper thumbnail of Both schizophrenic and bipolar adolescents differ from controls on MRI measures

Schizophrenia Research, 1998

Research paper thumbnail of Medicare hospital utilization increasing for schizophrenia

Schizophrenia Research, 1997

The prevalence, geographic variation and charges to Medicare of hospitalizations among disabled a... more The prevalence, geographic variation and charges to Medicare of hospitalizations among disabled and elderly people in the United States diagnosed with schizophren ia was investigated . Data was obtained from the HCFA 's Medicare inpatient claims files database for all Medicare Part A beneficiaries and 1990 census data. Two studies were conducted. First, a 6 year cross-sectional study examined the frequency of total annual admissions for patients diagnosed with schizophrenia from 1984 to 1989. The number of patients hospitalized with schizophrenia increased 48.6% from 1984 to 1989, and the frequency of total annual admissions increased by 57% from 88,679 in 1984 to 139,354 in 1989. Second, an 8 year prospective cohort study examined hospital utilization from 1984 to 1991. The sample consisted of 57,356 patients with schizophrenia requiring hospitalization during 1984: 72.8% (41,749) were disabled; 27.2% (15,607) were age 65 or older. For the 1984 cohort, there was considerable geographic variation in the prevalence of age-adjusted median rate of re-hospitalizations among patients diagnosed with schizophrenia: Iowa had the highest rate (4.08), and Utah had the lowest (1.95) . The overall length of hospital utilization had a mean of 37.2 days and a median of 12.0 days. Schizophrenia-related hospitalizations among patients on Medicare would appear common, and are producing considerable increases in Medicare expenditures. It is necessary to examine the role of state and federal mental health systems and expenditures in the increasing Medicare fund ing of hospitalizations for patients diagnosed with schizophrenia.

Research paper thumbnail of A study of head size in adult patients with schizophrenia

Schizophrenia Research, 1997

Research paper thumbnail of MRI measurements in adolescents with schizophrenia and bipolar disorder

Schizophrenia Research, 1997

Research paper thumbnail of Six year mortality rates following hospitalization for schizophrenia

Schizophrenia Research, 1997

The prevalence, geographic variation and charges to Medicare of hospitalizations among disabled a... more The prevalence, geographic variation and charges to Medicare of hospitalizations among disabled and elderly people in the United States diagnosed with schizophren ia was investigated . Data was obtained from the HCFA 's Medicare inpatient claims files database for all Medicare Part A beneficiaries and 1990 census data. Two studies were conducted. First, a 6 year cross-sectional study examined the frequency of total annual admissions for patients diagnosed with schizophrenia from 1984 to 1989. The number of patients hospitalized with schizophrenia increased 48.6% from 1984 to 1989, and the frequency of total annual admissions increased by 57% from 88,679 in 1984 to 139,354 in 1989. Second, an 8 year prospective cohort study examined hospital utilization from 1984 to 1991. The sample consisted of 57,356 patients with schizophrenia requiring hospitalization during 1984: 72.8% (41,749) were disabled; 27.2% (15,607) were age 65 or older. For the 1984 cohort, there was considerable geographic variation in the prevalence of age-adjusted median rate of re-hospitalizations among patients diagnosed with schizophrenia: Iowa had the highest rate (4.08), and Utah had the lowest (1.95) . The overall length of hospital utilization had a mean of 37.2 days and a median of 12.0 days. Schizophrenia-related hospitalizations among patients on Medicare would appear common, and are producing considerable increases in Medicare expenditures. It is necessary to examine the role of state and federal mental health systems and expenditures in the increasing Medicare fund ing of hospitalizations for patients diagnosed with schizophrenia.

Research paper thumbnail of Increased presence of white matter hyperintensities in adolescent patients with bipolar disorder

Psychiatry Research: Neuroimaging, 2002

Several reports have noted an increase in white matter hyperintensities (WMH) on MRI scans of adu... more Several reports have noted an increase in white matter hyperintensities (WMH) on MRI scans of adult patients with bipolar disorder. We investigated whether this increase was also evident in a group of adolescent patients with bipolar disorder. The sample consisted of 15 bipolar patients, 19 patients with schizophrenia and 16 healthy comparison subjects. All subjects were adolescents. WMH were blindly rated on T2-weighted and PD-weighted MRI scans using our own scale with documented inter-rater reliability. WMH were present in 10 of 15 bipolar patients (67%), seven of 19 patients with schizophrenia (37%) and five of 16 comparison subjects (31%). The bipolar adolescent group had a statistically significant increased presence of WMH compared both with healthy comparison subjects and the schizophrenic group. The association between WMH and bipolar disorder appears to extend to the adolescent years.

Research paper thumbnail of Hippocampal volume in adolescent schizophrenia

Schizophrenia Research, 1996

Research paper thumbnail of Pediatric Psychology Training: An Analysis of Graduate, Internship, and Postdoctoral Programs

Journal of Pediatric Psychology, 1989

The field of pediatric psychology is in the early stages of formulating its own identity relative... more The field of pediatric psychology is in the early stages of formulating its own identity relative to other areas, such as clinical child and health psychology. This paper complements other recent efforts to delineate training practices and guidelines. Questionnaires regarding doctoral, internship, and postdoctoral training experiences were obtained from 89% of the membership of the Society of Pediatric Psychology. From this information, rankings of the most commonly attended programs at each training level were derived. Some overlap was apparent between doctoral programs that were conducive to training in pediatric and clinical child psychology; however, differences between programs in these areas also were noted. The most commonly attended internship and postdoctoral settings were those in major medical centers or children's hospitals. Suggestions for investigating the current status of predoctoral, internship, and postdoctoral programs that may be facilitative of training in pediatric psychology are discussed.

Research paper thumbnail of Adolescent schizophrenia: A methodologic review of the current neuroimaging and neuropsychologic literature

Journal of Autism and Developmental Disorders, 1995

... Absent Gottschalk & Selin, 12 b Absent Absent 1991 Attention deficit 11 No Conduc... more ... Absent Gottschalk & Selin, 12 b Absent Absent 1991 Attention deficit 11 No Conduct disorder 21 Anxiety disorder 26 Adjustment disorder 20 No Conduct disorder 13 Dysthymic disorder 7Historionic personality 1 Depression (n = 8) No Conduct disorder (n = 2) Borderline (n = 2) ...

Research paper thumbnail of Adolescents With Diabetes: Gender Differences in Psychosocial Functioning and Glycemic Control

Children's Health Care, 1995

... Thomas Swales Case Western Reserve University ... for this possibility in part, we enrolled o... more ... Thomas Swales Case Western Reserve University ... for this possibility in part, we enrolled only adolescents who had diabetes for rnore than 1 year, as residual insulin secretion is typically greatest in the rnonths following the initial diagnosis of IDDM (Clarson, Daneman, Drash ...

Research paper thumbnail of 209. An MRI study of adolescent psychiatric patients and healthy controls

Biological Psychiatry, 1998

Research paper thumbnail of An MRI study of adolescent patients with either schizophrenia or bipolar disorder as compared to healthy control subjects

Biological Psychiatry, 1999

Background: There are few imaging studies in adolescent patients with either schizophrenia or bip... more Background: There are few imaging studies in adolescent patients with either schizophrenia or bipolar disorder. Such studies are of interest because adolescents may have a more severe illness and neurodevelopmental events may have a greater role in their pathophysiology. Methods: We compared 20 patients with schizophrenia and 15 patients with bipolar disorder (10 to 18 years) to 16 normal adolescents on magnetic resonance imaging (MRI) measures of intracranial volume and ventricular and sulcal enlargement. Two planned comparison contrasts were employed, one comparing the two patient groups to each other (contrast 1), and one comparing both patient groups combined to control subjects (contrast 2). Results: None of the contrast 1 comparisons (schizophrenia vs bipolar) were statistically significant. Contrast 2 comparisons (control subjects vs patients) were statistically significant for intracranial volume (reduced in patients) as well as frontal and temporal sulcal size (increased in patients). Conclusions: The patient groups were not statistically significantly different from each other on any measure. The combined patient groups were different from control subjects on intracranial volume and frontal and temporal sulcal size. Also, there was evidence for ventricular enlargement, after removal of a control subject with an extreme value. These findings indicate that the same abnormalities noted in adult populations are present in adolescents. Biol Psychiatry 1999;46:78 -88

Research paper thumbnail of Cognitive Impairment in Adolescents With Schizophrenia

American Journal of Psychiatry, 1997

Objective: The purpose of this study was to determine whether adolescent schizophrenia is charact... more Objective: The purpose of this study was to determine whether adolescent schizophrenia is characterized by neuropsychological deficits. Method: The performance on a battery of neuropsychological tests of 17 adolescents with schizophrenia (mean age=15.71 years) was compared with that of 17 normal adolescents (mean age=15.12 years). Results: Compared with the normal subjects, the patients were impaired on 10 of the 13 measures; larger effect sizes were shown for measures involving working memory and attention than for those involving secondary memory, generative naming, and executive functions. Conclusions: Adolescents with schizophrenia have generalized cognitive dysfunction, which is most apparent on tests of attention and working memory.