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Only two trials have compared acceptance and commitment therapy (ACT) and traditional cognitive behavior therapy (tCBT) in the treatment of social anxiety disorder (SAD), with both finding no significant differences. These trials did not examine effects on observer-rated behavioral outcomes and did not explicitly quantify the dose of exposure therapy within each treatment. In a replication trial, one hundred and two individuals with SAD (per DSM-IV criteria) were randomized to 12 sessions of ACT (n = 49) or tCBT (n = 53) controlling for exposure dose and assessing behavioral outcomes. Assessments were completed at pre- and post-treatment using clinician-rated and self-report measures of social anxiety, quality of life, and overall functioning. Observer-rated behavioral measures of social performance were completed for a subsample of participants. Results indicated that participants across conditions received equivalent doses of exposure. Those who received tCBT evidenced greater improvements in self-reported social anxiety symptoms and overall functioning, which contrasts with prior studies finding no differences between tCBT and ACT in the treatment of social anxiety. Medium effect sizes, while not statistically significant, indicate that ACT participants may have had greater improvements in observer-rated social behavior than tCBT participants. The discrepancy between these symptom and behavioral outcomes, building upon prior literature, calls for more research to assess the differences between tCBT and ACT treatments in behavioral domains.

People with schizophrenia (SZ) process emotions less accurately than do healthy comparators (HC), and emotion recognition have expanded beyond accuracy to performance variables like reaction time (RT) and confidence. These domains are typically evaluated independently, but complex inter-relationships can be evaluated through machine learning at an item-by-item level. Using a mix of ranking and machine learning tools, we investigated item-by-item discrimination of facial affect with two emotion recognition tests (BLERT and ER-40) between SZ and HC. The best performing multi-domain model for ER40 had a large effect size in differentiating SZ and HC (d = 1.24) compared to a standard comparison of accuracy alone (d = 0.48); smaller increments in effect sizes were evident for the BLERT (d = 0.87 vs. d = 0.58). Almost half of the selected items were confidence ratings. Within SZ, machine learning models with ER40 (generally accuracy and reaction time) items predicted severity of depression and overconfidence in social cognitive ability, but not psychotic symptoms. Pending independent replication, the results support machine learning, and the inclusion of confidence ratings, in characterizing the social cognitive deficits in SZ. This moderate-sized study (n = 372) included subjects with schizophrenia (SZ, n = 218) and healthy controls (HC, n = 154)., Highlights • This paper explores the value of integrative evaluation of confidence, accuracy, and reaction time by way of machine learning in understanding the unique aspects of facial affect recognition in schizophrenia. • Machine learning models better separated schizophrenia from healthy comparators that standard statistical comparison, confidence ratings contributed to this separation in a disproportionate manner. • Machine learning approaches provide a novel way to analyze item-by-item associations with social cognition measures, or potentially other tests, where multiple overlapping dimensions exist. • Aberrant confidence ratings interact with performance variables in complex ways to contribute to social cognitive deficits in schizophrenia.

The retina of the adult teleost fish is an important model for studying persistent and injury-induced neurogenesis in the vertebrate central nervous system. All neurons, with the exception of rod photoreceptors, are continually appended to the extant retina from an annulus of progenitors at the margin. Rod photoreceptors, in contrast, are added to differentiated retina only from a lineage of progenitors dedicated to making rods. Further, when the retina is lesioned, the lineage that produces only rods ceases this activity and regenerates retinal neurons of all types. The progenitors that supply neurons at the retinal margin and rod photoreceptors and regenerated neurons in the mature tissue originate from multipotent stem cells. Recent data suggest that the growth-associated neurogenic activity in the retina is regulated as part of the growth hormone/insulin-like growth factor-I axis. This paper reviews recent evidence for the presence of stem cells in the teleost retina and the molecular regulation of neurogenesis and presents a consensus cellular model that describes persistent and injury-induced neurogenesis in the retinas of teleost fish.

Astrocytes have been implicated in axon guidance and synaptic regeneration in the retina and these processes involve activation of the high affinity nerve growth factor receptor, known as the tyrosine kinase A (TrkA) receptor. The purpose of the present study was to characterize the expression of TrkA in astrocytes of the adult pig and human retina. To this end, sections of human and pig retinas were immunolabeled with a combination of antibodies to glial fibrillary acidic protein (GFAP) and TrkA. Our study revealed that most of the GFAP-positive cells express TrkA, whereas a rare, novel subpopulation of astrocytes was found to be devoid of TrkA. Our results support the idea that astrocytes play an important neurotrophic role in the retina.

The retinas of teleost fish grow continuously, in part, by neuronal hyperplasia and when lesioned will regenerate. Within the differentiated retina, the growth-associated hyperplasia results in the generation of new rod photoreceptors only, whereas injury-induced neurogenesis results in the regeneration of all retinal cell types. It is believed, however, that both new rod photoreceptors and regenerated neurons originate from the same populations of intrinsic progenitors. Experiments are described here that attempt to identify in the normal retina of goldfish neuronal progenitors intrinsic to the retina, particularly those which have remained cryptic because they divide infrequently. Long-term, systemic exposure to bromodeoxyuridine (BrdU) was used to label these cells. Five populations of proliferative cells were labeled: microglia, which are briefly described but not studied further; retinal progenitors in the circumferential germinal zone (CGZ); and rod precursors in the outer nuclear layer (ONL), both of which have been well characterized previously; and two populations of slowly-dividing cells in the inner nuclear layer (INL). The majority of these cells have a fusiform morphology, whereas the remaining ones are spherical. Longitudinal BrdU labeling suggests that the fusiform cells migrate to the ONL to replenish the pool of rod precursors. A subset of the spherical cells express pax6, although none are stained with markers of differentiated amacrine or bipolar cells. It is hypothesized that these rare, pax6-expressing cells are retinal stem cells, which give rise to the pax6-negative fusiform cells. Based on these data, two models are proposed: the first describes the lineage of rod photoreceptors in goldfish; the second is a consensus model of neurogenesis in the retinas of all teleosts.

The mouse neurological mutant lethargic (lh) is characterized by ataxia, focal myoclonus, and absence epilepsy due to a loss-of-function mutation in the beta4 subunit of the voltage-gated calcium channel. To evaluate the role of this channel subunit in human neurological disease, we determined the chromosomal location and intron/exon structure of the human CACNB4 gene. The 1560-bp open reading frame of the CACNB4 cDNA predicts a 58-kDa protein with an amino acid sequence that is 99% identical to the rat protein. The 13 coding exons of CACNB4 span >55 kb of genomic DNA. Human cerebellar RNA contains one major CACNB4 transcript that is 9 kb in length. Expression of CACNB4 was detected in cerebellum, kidney, testis, retina, lymphoblasts, and circulating lymphocytes. Retinal transcripts were localized by in situ hybridization to ganglion cells and the inner nuclear layer. Analysis of the GeneBridge 4 radiation hybrid mapping panel localized CACNB4 to position 791 cR on human chromosome 2, in a conserved linkage group on human 2q22-q31 and mouse chromosome 2. We localized CACNB4 to the 1.3-Mb YAC clone 952F10 in Whitehead contig WC861, along with the polymorphic markers D2S2236 and D2S2299. The chromosomal linkage of three of the four beta subunit genes to homeobox gene clusters associates the evolutionary origin of the beta gene family with the events that generated the four HOX clusters early in vertebrate evolution.

Tritiated thymidine [(3H]thymidine) autoradiographic techniques have been used to define birthdates for cells in a variety of animals. In an effort to include [3H]thymidine experiments in our ongoing studies of visual system development, we have used an intrauterine injection procedure that affords [3H]thymidine labeling of dividing nerve cells in the cat. This report contains a detailed description of the injection procedures used, as well as the results of experiments undertaken to define the period of time during which the exogenous [3H]thymidine introduced by such injections remains available for uptake.

The dendritic growth of amacrine cells was studied in the retina of the goldfish. Those cells that accumulated the intraocularly injected fluorescent dye 4,6-diamidino-2-phenylindole (DAPI) were compared in retinal wholemounts from small and large animals. Dendritic arbors were stained by intracellular injections of Lucifer yellow. Based upon their dendritic morphology, two types were identified, radiate and fusiform. The dendritic field areas and the number of dendritic terminals were quantitatively compared for cells in small retinas from young fish and large retinas from old fish in the region of the retina that grows by expansion. For both cell types the dendritic fields were significantly larger in the large retinas. The radiate cells had the same number of dendritic terminals in retinas of both sizes, whereas the fusiform cells in the large retinas had significantly more dendritic terminals than those in the small retinas. This resulted from the addition of new dendrites to the proximal arbor. These data show that with retinal expansion the pattern of dendritic growth by a amacrine cells is cell-type specific.