The biology of thymic stromal lymphopoietin (TSLP)

Originally shown to promote the growth and activation of B cells, thymic stromal lymphopoietin (TSLP) is now known to have wide-ranging impacts on both hematopoietic and nonhematopoietic cell lineages, including dendritic cells, basophils, eosinophils, mast cells, CD4⁺, CD8⁺ and natural killer T cells, B cells and epithelial cells. While TSLP's role in the promotion of TH2 responses has been extensively studied in the context of lung- and skin-specific allergic disorders, it is becoming increasingly clear that TSLP may impact multiple disease states within multiple organ systems, including the blockade of TH1/TH17 responses and the promotion of cancer and autoimmunity. This chapter will highlight recent advances in the understanding of TSLP signal transduction, as well as the role of TSLP in allergy, autoimmunity and cancer. Importantly, these insights into TSLP's multifaceted roles could potentially allow for novel therapeutic manipulations of these disorders.

The transcription factor STAT5 is critical in dendritic cells for the development of TH2 but not TH1 responses

Dendritic cells (DCs) are critical in immune responses, linking innate and adaptive immunity. We found here that DC-specific deletion of the transcription factor STAT5 was not critical for development but was required for T helper type 2 (TH2), but not TH1, allergic responses in both the skin and lungs. Loss of STAT5 in DCs led to the inability to respond to thymic stromal lymphopoietin (TSLP). STAT5 was required for TSLP-dependent DC activation, including upregulation of the expression of costimulatory molecules and chemokine production. Furthermore, TH2 responses in mice with DC-specific loss of STAT5 resembled those seen in mice deficient in the receptor for TSLP. Our results show that the TSLP-STAT5 axis in DCs is a critical component for the promotion of type 2 immunity at barrier surfaces.

Loss of epigenetic modification driven by the Foxp3 transcription factor leads to regulatory T cell insufficiency

Regulatory T (Treg) cells, driven by the Foxp3 transcription factor, are responsible for limiting autoimmunity and chronic inflammation. We showed that a well-characterized Foxp3(gfp) reporter mouse, which expresses an N-terminal GFP-Foxp3 fusion protein, is a hypomorph that causes profoundly accelerated autoimmune diabetes on a NOD background. Although natural Treg cell development and in vitro function are not markedly altered in Foxp3(gfp) NOD and C57BL/6 mice, Treg cell function in inflammatory environments was perturbed and TGF-β-induced Treg cell development was reduced. Foxp3(gfp) was unable to interact with the histone acetyltransferase Tip60, the histone deacetylase HDAC7, and the Ikaros family zinc finger 4, Eos, which led to reduced Foxp3 acetylation and enhanced K48-linked polyubiquitylation. Collectively this results in an altered transcriptional landscape and reduced Foxp3-mediated gene repression, notably at the hallmark IL-2 promoter. Loss of controlled Foxp3-driven epigenetic modification leads to Treg cell insufficiency that enables autoimmunity in susceptible environments.

The multiple facets of thymic stromal lymphopoietin (TSLP) during allergic inflammation and beyond

Originally shown to promote the growth and activation of B cells, TSLP is now known to have wide-ranging impacts on hematopoietic and nonhematopoietic cell lineages, including DCs, basophils, eosinophils, mast cells, CD4(+), CD8(+), and NK T cells, B cells, and epithelial cells. Whereas the role of TSLP in the promotion of TH2 responses has been studied extensively in the context of lung- and skin-specific allergic disorders, it is becoming increasingly clear that TSLP may impact multiple disease states within multiple organ systems, including the blockade of TH1/TH17 responses and the promotion of cancer and autoimmunity. This review will highlight recent advances in the understanding of TSLP signal transduction, as well as the role of TSLP in allergy, autoimmunity, and cancer. Importantly, these insights into the multifaceted roles of TSLP could potentially allow for novel, therapeutic manipulations of these disorders.

Urinary hormone metabolites identify sex and imply unexpected winter breeding in an endangered, subterranean-nesting frog

Urinary hormone analysis has proved accurate for identifying sex and breeding periods in dimorphic amphibians with known reproductive cycles. We examined whether these techniques could provide this much needed information for a monomorphic anuran with an unconfirmed mating season in the wild. We analysed urinary estrone conjugate, testosterone, and progesterone metabolites to infer the time of breeding and to identify sex in the endangered Maud Island frog, Leiopelma pakeka. Testosterone metabolites in males and estrone and progesterone metabolites in females were at their peak during winter for both wild and captive frogs. These urinary metabolite patterns were consistent with the high proportion of females exhibiting enlarged ovarian follicles in winter months. Sex identification based on urinary estrone metabolite levels was 94% correct in this monomorphic species, in which the sexes overlap in snout-to-vent length (SVL) for over half of their adult size range and in which no other sexually dimorphic trait is known. The seasonal profiles imply unexpected winter or early spring breeding in L. pakeka. Overall, these results demonstrate use of urinary hormone metabolites for reproductive monitoring and sex identification in one of the world's most threatened and evolutionarily distinct amphibians.

T cell intrinsic roles of autophagy in promoting adaptive immunity

Autophagy, an ancient cellular response where autophagic vacuoles are formed within the cytosol, is induced in response to a variety of cellular insults, including growth factor or nutrient withdrawal, organelle damage, and misfolded proteins. Autophagy is rapidly induced in T lymphocytes following antigenic stimulation and blockade of autophagic signaling greatly reduces T cell clonal expansion, suggesting that autophagy is primarily involved in promoting T cell survival. In contrast, a recently identified negative feedback loop involving FADD and caspase-8 limits the level of autophagy in T cells. Failure to activate caspase-8 during T cell mitogenesis leads to hyperactive autophagy and cellular death through a programmed necrotic mechanism. These findings suggest that crosstalk between these cellular processes is essential for T cell activation and homeostasis.

Non-apoptotic caspase-8 activation balances T lymphocyte autophagy (82.14)

Apoptosis and autophagy are critical mediators of a functional immune response. FADD and caspase-8 (casp8) were originally discovered to transduce apoptotic signals delivered through TNF family members. Paradoxically, lymphocytes lacking FADD or casp8 function have impaired clonal expansion following antigen receptor crosslinking and succumb to a caspase-independent cell death. We show that T cells lacking FADD or casp8 are subject to hyperactive autophagy. T cell autophagy induces casp8 activation through its interaction with FADD:Atg5:Atg12 complexes. Blockade of autophagic signaling with shRNA knockdown of the autophagy-dependent protein Atg7 leads to a rescue of T cells lacking FADD and casp8. Similarly, inhibition of RIPK1 kinase activity with necrostatin-1 completely restored T cell cycle and survival. We hypothesize that the non-apoptotic casp8 activity serves to dampen the autophagic response of proliferating T cells through direct cleavage of RIPK1 or the casp8 homolog, c-FLIP, which may secondarily inhibit RIPK1-dependent authophagic signaling. While rapidly dividing T cells require autophagy, this negative feedback loop can prevent hyperactive autophagy. Linking apoptotic proteins to this signaling paradigm may serve to prevent an inflammatory response driven by autophagic cell death in lymphocytes during an immune response. (Funded by NIH T32CA09054 to B.D.B. and R01AI63419 to C.M.W.)

Coordinate regulation of autophagy and apoptosis in T cells by death effectors: FADD or foundation

During an immune response, specific recognition of microbial and tumor antigens leads to the rapid proliferation of lymphocytes. Once the immunological challenge is eliminated, the vast majority of these lymphocytes must be removed via apoptosis. Cell death is also vital for the deletion of autoreactive or chronically activated lymphocytes to prevent the development of autoimmunity in the host. Such processes are highly dependent on death receptors (DRs), molecules of the TNF receptor family. While these DRs promote apoptosis, interference with DR signaling paradoxically interferes with rapid lymphocyte proliferation. Recently, we discovered that T cells lacking Fas-Associated protein with Death Domain (FADD) or caspase-8 (casp8) function, both essential for DR-induced apoptosis, succumb to hyperactivation of autophagy and die through a nonapoptotic form of cell death rather than proliferating after mitogen stimulation. We observed recruitment of FADD, casp8 and serine/threonine kinase RIPK1 to complexes containing Atg5, Atg12 and Atg16L, suggesting that the generation of early autophagosomes leads to the assembly of complexes that activate casp8. Because blockade of RIPK1 or interference with autophagic signaling inhibited this alternative death process, we propose that hyperactive autophagy induced in the absence of caspase activity leads to a necrosis-like form of death that depends on RIPK1 enzymatic function. Herein, we summarize these findings and speculate on the significance and means by which autophagy is normally activated in proliferating lymphocytes.

A Fas-associated death domain protein/caspase-8-signaling axis promotes S-phase entry and maintains S6 kinase activity in T cells responding to IL-2

Fas-associated death domain protein (FADD) constitutes an essential component of TNFR-induced apoptotic signaling. Paradoxically, FADD has also been shown to be crucial for lymphocyte development and activation. In this study, we report that FADD is necessary for long-term maintenance of S6 kinase (S6K) activity. S6 phosphorylation at serines 240 and 244 was only observed after long-term stimulation of wild-type cells, roughly corresponding to the time before S-phase entry, and was poorly induced in T cells expressing a dominantly interfering form of FADD (FADDdd), viral FLIP, or possessing a deficiency in caspase-8. Defects in S6K1 phosphorylation were also observed. However, defective S6K1 phosphorylation was not a consequence of a wholesale defect in mammalian target of rapamycin function, because 4E-BP1 phosphorylation following T cell activation was unaffected by FADDdd expression. Although cyclin D3 up-regulation and retinoblastoma hypophosphorylation occurred normally in FADDdd T cells, cyclin E expression and cyclin-dependent kinase 2 activation were markedly impaired in FADDdd T cells. These results demonstrate that a FADD/caspase-8-signaling axis promotes T cell cycle progression and sustained S6K activity.

A non-apoptotic FADD/caspase-8 dependent mechanism essential for T cell clonal expansion (87.48)

FADD constitutes an essential component of TNF receptor-induced apoptotic signaling. Paradoxically, FADD has also been shown to be crucial for lymphocyte development and activation. Using mice expressing a T cell specific transgene encoding the death domain of FADD (FADDdd), we have found that FADD participates in T cell clonal expansion. Based on BrdU uptake assays, we have found that FADD signaling is required for transition between the late G1 and S-phase of cell cycle. The defective progression through cycle is marked by a defect in cyclin E expression and CDK2 activation. We have also identified a defect in the maintenance of S6K1 activity and ribosomal S6 phosphorylation, two essential intermediaries of proliferative signaling in T cells. We have found that caspase-8 is essential in this FADD dependent process, suggesting that FADD promotes the assembly of a non-apoptotic caspase-8 complex that serves to relieve inhibition of cell cycle progression during the G1/S transition. In line with this hypothesis, we have found that caspase-8 activity is induced in T cells in a cell-cycle dependent manner in normal T cells. The potential that this signaling axis may modulate autophagy is presently under investigation. Since TNF receptor family members play key roles in regulating adaptive immunity, these results suggest that FADD and caspase-8 serve multiple functions to maintain immune homeostasis.

Cutting edge: FADD is not required for antigen receptor-mediated NF-kappaB activation

Recently, it has been demonstrated that stimulated T cells bearing defects in caspase-8 fail to promote nuclear shuttling of NF-kappaB complexes. Such cells display strikingly similar proliferative and survival defects as T cells lacking Fas-associated death domain protein (FADD) function. We characterized NF-kappaB signaling in T cells bearing a dominant-negative FADD transgene (FADDdd). Whereas FADDdd T cells displayed proliferative defects following activation, these were not a consequence of aberrant NF-kappaB signaling, as measured by IKK/IkappaB phosphorylation and IkappaB degradation. There were no appreciable defects in nuclear translocation of p65/Rel using ImageStream, a flow-based imaging cytometer. Pretreatment with benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone, a potent caspase inhibitor, also failed to impede canonical NF-kappaB signaling. Secretion of IL-2 and up-regulation of various activation markers occurred normally. Thus, FADD does not play an essential role in NF-kappaB activation, suggesting an alternative route by which this adaptor promotes the clonal expansion of T cells.

Object naming and semantic knowledge in temporal lobe epilepsy

Object-naming impairment is common among temporal lobe epilepsy (TLE) patients, but other aspects of semantic memory have received limited attention in this population. This study examined object-naming ability and depth of semantic knowledge in healthy controls (n = 29) and patients with early onset TLE (n = 21). After administration of the Boston Naming Test (BNT), the authors asked participants to provide detailed definitions of 6 BNT objects. The TLE group demonstrated a significant deficit relative to controls in both object-naming ability and semantic knowledge for the target objects, even after controlling for IQ. In a multiple regression analysis that included other neuropsychological test scores as independent variables, the semantic knowledge score was the only significant predictor of patients' object-naming performance. Thus, at the group level, early onset TLE patients have a semantic knowledge deficit that contributes to dysnomia.

Object naming and semantic knowledge in temporal lobe epilepsy

Object-naming impairment is common among temporal lobe epilepsy (TLE) patients, but other aspects of semantic memory have received limited attention in this population. This study examined object-naming ability and depth of semantic knowledge in healthy controls (n = 29) and patients with early onset TLE (n = 21). After administration of the Boston Naming Test (BNT), the authors asked participants to provide detailed definitions of 6 BNT objects. The TLE group demonstrated a significant deficit relative to controls in both object-naming ability and semantic knowledge for the target objects, even after controlling for IQ. In a multiple regression analysis that included other neuropsychological test scores as independent variables, the semantic knowledge score was the only significant predictor of patients' object-naming performance. Thus, at the group level, early onset TLE patients have a semantic knowledge deficit that contributes to dysnomia.

Pediatric epilepsy surgery: neuroimaging, neuropsychology, and anticonvulsants

Neuroimaging and the neuropsychological evaluation are important components of the presurgical evaluation for epilepsy surgery. Advances in neuroimaging over the last decade, to a large part, underlie improvements in pediatric epilepsy surgery outcomes. The neuropsychological evaluation plays an important role in the evaluation of the older child and adolescent, particularly in the evaluation of mesial temporal sclerosis. However, its role in the young child being considered for surgery remains to be defined. This section reviews the definition of medical intractability, issues related to medication withdrawal during video-EEG monitoring, recent neuroimaging advances, and the neuropsychological evaluation.

Intracarotid amobarbital procedure and prediction of postoperative memory in patients with left temporal lobe epilepsy and hippocampal sclerosis

PURPOSE

Although temporal lobe epilepsy (TLE) patients with dominant hemisphere hippocampal sclerosis generally have good cognitive outcome after anterior temporal lobectomy (ATL), a minority of patients experience at least mild post-ATL decline on one or more standardized measures of episodic and semantic memory. The goal of this investigation was to determine whether memory outcome in this group could be predicted from preoperative intracarotid amobarbital procedure (IAP) recognition memory scores.

METHODS

Data from 22 left TLE patients were studied retrospectively. All were left hemisphere language dominant and had IAP scores for each hemisphere, a significant degree of pathology-confirmed left hippocampal sclerosis (HS+), and no positive MRI findings other than atrophy. Cognitive outcome status was represented by the number of pre- to post-ATL declines across three tests, as defined by 90th percentile Reliable Change Index (RCI) criteria.

RESULTS

Only 14% of the sample exhibited decline on more than one memory test. Low right IAP (left hemisphere injection) scores and relatively high preoperative cognitive ability and age at surgery predicted a greater risk of post-ATL memory decline.

CONCLUSIONS

A minority of left TLE HS+ patients experience at least a mild degree of RCI-defined decline in episodic or semantic memory after ATL. The right hemisphere IAP memory score, which reflects the functional reserve of the contralateral hemisphere, can help predict the risk of postoperative memory decline for TLE patients in whom HS+ is likely based on the presence of hippocampal atrophy on MRI or early age of seizure onset.

Confrontation naming after anterior temporal lobectomy is related to age of acquisition of the object names

Decline in visual confrontation naming ability may occur as a postacute complication of left anterior temporal lobectomy (ATL) for the treatment of intractable mesial temporal lobe epilepsy. In this study of 26 left ATL patients who demonstrated postsurgery decline on a standardized naming measure, it was hypothesized that naming performance would be significantly associated with specific attributes of the object names. We investigated the relation between performance on the Boston Naming Test (BNT) and the following attributes of the test items: living versus nonliving category (L/NL), word length (WL), written word frequency (WF), and age of acquisition (AoA). Regression analyses revealed that AoA and WF were significant predictors of preoperative group performance. AoA was the only significant predictor of performance after left ATL. For the 17 individuals who demonstrated a statistically meaningful decline on the BNT, as indicated by a Reliable Change Index, individual logistic regressions demonstrated that AoA was the strongest and most consistent predictor of postoperative success/failure for items that had been named correctly preoperatively. Consistent with the literature on naming errors in elderly normals and patients with aphasia or semantic dementia, the results provide evidence that object names learned in late childhood are among the most vulnerable when there is a decline in object naming ability. Investigation of additional attributes and semantic knowledge for the concepts represented by the pictured objects will be necessary to determine whether the naming deficit associated with TLE and ATL reflects an impairment of phonological word-form retrieval, semantics, or both.

Neuropsychological functioning in migraine headache, nonheadache chronic pain, and mild traumatic brain injury patients

There are conflicting reports in the literature concerning the neuropsychological functioning of migraine headache patients. The finding in some studies that migraineurs performed more poorly than healthy controls led to the hypothesis that chronic migraine may result in subtle but persistent cerebral dysfunction. Reports describing acute and between-headache neurophysiological disturbances in migraineurs lent support to this hypothesis. To elucidate the cognitive status of these patients, we administered a brief neuropsychological battery to 60 individuals with migraine headache (HA), nonheadache chronic pain (PAIN), or mild traumatic brain injury (MTBI). The PAIN group was included to test the hypothesis that cognitive difficulty in migraineurs might result from the discomfort, depression, medications, etc. often associated with chronic pain, rather than from brain dysfunction. The MTBI patients were considered a useful comparison for the migraineurs because their level of impairment was also expected to be mild, at worst. A MANOVA, with three cognitive index scores as the dependent variables, revealed that the three groups differed significantly. Follow-up contrasts demonstrated that the MTBI group was significantly more impaired on the memory index compared to the HA and PAIN groups, which did not differ from each other. The use of two different normative-based cutoffs to identify individuals who were impaired on the test battery revealed that the frequency of impairment within the two groups of pain patients, but not the MTBI patients, was within normal limits. Thus, the results did not support a link between migraine headache and cognitive impairment.

Prediction of presence of hippocampal sclerosis from intracarotid amobarbital procedure memory asymmetry scores and epilepsy on set age

Identification of the pathological status of the hippocampus prior to surgery is important since the absence of hippocampal sclerosis (HS) carries risks to memory function following anterior temporal lobectomy (ATL). We studied 62 patients undergoing ATL (31 L, 31 R) for intractable epilepsy of temporal lobe origin in whom no pathology was identified apart from HS. An intracarotid amobarbital procedure (IAP) was performed as part of the preoperative evaluation. All patients were left hemisphere dominant for language. IAP memory testing was according to the protocol of Loring. We examined IAP memory asymmetry scores at four levels of difference (<2, > or =2, > or =4, > or =6) as a function of the presence (HS+) or absence (HS-) of HS. A logistic regression analysis was performed with HS+ as the dependent variable, and age at onset of epilepsy, age at time of surgery, gender, side of surgery and significant IAP memory asymmetry as independent variables. At each level of memory asymmetry, onset age and memory asymmetry were the only predictors of HS+. Younger age at onset was associated with HS+. Curves were constructed showing probability of HS+ for age at onset for each level of asymmetry. These can be used to predict the likelihood of presence of HS based on age at onset of epilepsy and the IAP memory asymmetry score. It is concluded that IAP memory asymmetry scores reflect the functional and pathological status of the hippocampus, and greater asymmetry increases the probability of finding HS in the resected hippocampus.

Avoidance in trauma: conscious and unconscious defense, pathology, and health

Drawing from our work with children seen following the 1995 bombing of the Alfred P. Murrah Federal Building in Oklahoma City, Oklahoma, this article describes clinical aspects of avoidance in traumatized children and their families. Avoidance in traumatized children and their families seems a final common pathway arising from a number of diverse factors. The importance of particular factors for assessment and treatment is emphasized.

Prediction of verbal memory loss in individuals after anterior temporal lobectomy

PURPOSE

Decreased memory function represents the area of greatest neuropsychological morbidity after anterior temporal lobectomy (ATL), particularly for left ATL candidates. We wished to identify easily derived demographic and neuropsychological predictors of risk of pre- to postoperative memory decline using only information available preoperatively.

METHODS

We assessed decline in memory as measured by the California Verbal Learning Test (CVLT) by deriving multiple regression equations using the following measures as independent variables: age at onset, chronological age at time of surgery, sex, Full Scale IQ (FSIQ), level of education, and preoperative memory scores. In all, 203 patients (93 males, 110 females), undergoing ATL (107 left, 96 right) with preoperative and 6-month postoperative testing, were examined.

RESULTS

The combination of age, FSIQ, sex, side of surgery and preoperative score was highly predictive (p-values < 0.0001) of postoperative memory scores. Higher postoperative scores were associated with higher preoperative score, younger chronological age, higher FSIQ, female sex, and right side of resection. Reliable change index (RCI) values were used to estimate meaningful decline on the total score across five trials. Logistic regression analysis showed preoperative score and age to be predictors of RCI decline for left-sided resections. Sensitivity of decline (> or =90th centile RCI) prediction was 56%, and specificity was 95%. Validation in 30 patients from a separate population of patients undergoing left ATL produced similar figures.

CONCLUSIONS

The derived regression equations can accurately predict verbal memory decline on a list-learning task in approximately 50% of individual patients undergoing ATL, and false-positive prediction errors are very rare.

Naming decline after left anterior temporal lobectomy correlates with pathological status of resected hippocampus

PURPOSE

To evaluate the determinants of postoperative change in visual confrontation naming ability and the differential sensitivity of two common tests of confrontation naming.

METHODS

In a group of 99 patients undergoing lobectomy of the left, language-dominant anterior temporal lobe, we examined naming ability using two measures: the 60 item Boston Naming Test (BNT), and the Visual Naming (VN) subtest of the Multilingual Aphasia Examination (MAE). ATL entailed resection of lateral temporal lobe followed by microsurgical complete removal of hippocampus. Language mapping was not performed. The status of the resected hippocampus was graded on a scale 0-4 of hippocampal sclerosis (HS). A dichotomous grouping HS- (grades 0 and 1, n = 34) and HS+ (grades 3 and 4, n = 61) was effected. Age at surgery, age of epilepsy onset, sex, extent of lateral temporal resection, Full-Scale IQ (FSIQ), and preoperative naming scores were also examined as potential predictors of pre- versus postoperative naming change.

RESULTS

Preoperative BNT and VN scores were significantly worse for HS+ than for HS- (BNT, p < 0.05; VN, p = 0.001). Postoperatively, BNT and VN scores significantly declined for HS- as compared with HS+ patients (p < 0.001). For individual risk, the 90th centile of reliable change index (RCI) was used. By this criterion, of the total sample, 39% evidenced decline on the BNT and 17% evidenced decline on the VN. Logistic regression analysis with backward elimination showed HS to be the only predictor of decline in BNT and HS and sex to be the only predictors of VN decline. Males were more at risk than females. Age, age at onset, extent of lateral resection, preoperative scores, and FSIQ were not predictors. Using age at onset as a proxy for HS+/HS- we calculated probabilities for naming decline for given onset age.

CONCLUSIONS

Both preoperative and postoperative change in naming ability are associated with the pathological status of the hippocampus. The potential interpretations and implications of these findings are discussed.

Anterior temporal lobectomy, hippocampal sclerosis, and memory: recent neuropsychological findings

Anterior temporal lobectomy (ATL) is an effective and increasingly utilized treatment for nonlesional, intractable mesial temporal lobe epilepsy. However, this surgery results in domain-specific neuropsychological morbidity for a subset of patients. Within the past decade, multidisciplinary studies have revealed that left ATL patients without significant sclerosis in the resected hippocampus are most at risk for a substantial postacute decline in the ability to encode new verbal information. These patients are also at risk for a significant decrement in confrontation naming and other retrieval-based language abilities. The memory deficit is not attributable to this disruption of language. A relationship between hippocampal sclerosis (HS) status and memory performance has not been identified consistently in right ATL patients, but investigation of new visuospatial measures continues. The influence of variables other than HS on neuropsychological outcome is also discussed.

Pantomime recognition impairment in aphasia: an analysis of error types

Aphasic patients were administered a pantomine recognition test (PRT) and two verbal comprehension tests with the same perceptual-motor, semantic, and neutral response foils in a test of the hypothesis that both pantomime and verbal comprehension impairments reflect the same underlying aphasic disorder. Perceptual-motor errors were significantly more common than semantic and neutral errors on the PRT, whereas semantic errors were significantly more common on the combined verbal tests. The results support the view that errors in pantomime recognition among aphasic patients may occur as a function of a deficit in perceptual-motor ability in addition to semantic impairment. Pantomime recognition performance did not correlate significantly with measures of language or praxis.

Life satisfaction and occupational retirement: beyond the impact year

This article examines three theoretical perspectives relative to the prediction of life satisfaction following retirement. Hypotheses derived from crisis, continuity, and consistency theories were systematically examined with regard to the pre- and post-retirement satisfaction scores of 114 male respondents (mean age 69 years). The data confirm one of four crisis hypotheses. Specifically, individuals underwent a decline in satisfaction with retirement. Similarly, only one of three continuity hypotheses was partially confirmed. A positive association obtained between safisfaction and orientational change in the voluntary association area. Contrary to the theory, however, respondents underwent a significant decline in satisfaction. Finally, only one of the consistency hypotheses was substantiated. In general, expectational disconfirmations relative to retirement did not result in lowered satisfaction.

The impact of housing relocation on the elderly: an alternative methodological approach

This article examines the impact of housing relocation on the patterns of interaction and life satisfaction of a sample of older, married adults living in an urban area of central Arkansas. Interviews were conducted with 115 individuals residing in congregate housing and with a matched sample of 105 persons living in independent residential units. Respondents in the two settings fail to demonstrate significant differences in frequencies of social interaction. Patterns of interaction in five specific areas also reveal no appreciable variation. In addition, the time-related effects of congregate dwelling are suggestive but not confirming of negative changes in both interaction and satisfaction. On the other hand, regardless of residential duration, health, sex or age, independent residents exhibit higher life satisfaction. The data suggest the congregate setting to possess insufficient resources to offset the objective and subjective decrements of old age.

The limitations of crisis theory as an explanatory mechanism in social gerontology

This study examines five specific assumptions of crisis theory as this orientation relates to the prediction of life satisfaction following retirement. Pre-retirement and post-retirement interviews were conducted with a group of 114 men (mean age 68.2 years) residing in an urban area of central Missouri. The data reveal a significant decline in life satisfaction as predicted. Contrary to the theory, however, no significant changes in role behavior in three related areas-family, voluntary associations, and community--were found subsequent to retirement. In addition, the role changes accompanying retirement were not significantly associated with negative changes in satisfaction. Also, increases in role performance were not significantly related to positive changes in satisfaction. Finally, the correlation between work commitment and change in satisfaction proved negative and non significant. On the other hand, the correlation between work commitment and the desire for subsequent employment was negative and significant. In sum, four of the five assumptions of crisis theory do not receive support on the basis of the data.