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1.
J Ethn Subst Abuse ; 22(1): 133-153, 2023.
Article in English | MEDLINE | ID: mdl-33829961

ABSTRACT

This study explored perceptions of marijuana use and abstinence among urban and rural Appalachian high school students using photovoice, enabling this subset of youth to co-construct their perceptions of marijuana use and abstinence. Twelve adolescents, ages 14-17, participated in the study. Participants identified managing stress and feeling peer pressure as two reasons teens might use marijuana. Participants identified four reasons for adolescent marijuana abstinence including having positive relationships, identifying with religion/spirituality, participating in extracurricular activities, and avoiding negative outcomes. Findings suggest that participants may smoke marijuana due to peer pressure and to cope with stress. Collective approaches including families, communities, and faith organizations may be important marijuana use prevention approaches for Appalachian adolescents.


Subject(s)
Cannabis , Marijuana Smoking , Marijuana Use , Substance-Related Disorders , Adolescent , Humans
2.
JACC Basic Transl Sci ; 6(3): 189-198, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33778208

ABSTRACT

Exercise intolerance remains one of the major factors determining quality of life in heart failure patients. In 6 patients with heart failure with preserved ejection fraction (HFpEF) undergoing invasive cardiopulmonary exercise testing, balloon inflation within the inferior vena cava (IVC) was performed during exercise to reduce and maintain pulmonary arterial (PA) pressures. Partial IVC occlusion significantly reduced PA pressures without reducing cardiac output. Partial IVC occlusion significantly reduced respiratory rate at matched levels of exercise. These findings highlight the importance of pulmonary pressures in the pathophysiology of HFpEF and suggest that therapies targeting hemodynamics may improve symptoms and exercise capacity in these patients.

3.
Respiration ; 98(2): 165-170, 2019.
Article in English | MEDLINE | ID: mdl-31048594

ABSTRACT

BACKGROUND: Despite an improved understanding of the pathophysiology of asthma, severe asthma sufferers continue to experience a poor quality of life (QOL). Bronchial thermoplasty (BT) utilizes thermal energy to reduce airway smooth muscle. In industry-sponsored trials, BT improves QOL and reduces severe exacerbations; however, the impact of BT on asthma-related QOL and medication use in non-industry-sponsored trials is less clear. OBJECTIVE: The aim of this study was to determine the impact of BT on asthma QOL measures (mini-AQLQ) and asthma controller medication use during the year following treatment with BT. METHODS: We performed a prospective study of the impact of BT in 25 patients with severe persistent asthma. Our primary outcome was change in asthma-related QOL score (mini-AQLQ) 1 year after BT treatment. Our secondary outcome was change in asthma medication use 1 year after BT. RESULTS: BT led to an improvement in mini-AQLQ score from a baseline of 3.6 ± 0.3 before therapy to 5.6 ± 0.3 1 year after the final BT procedure. Overall, 88% percent of patients showed a clinically significant improvement in mini-AQLQ at 1 year. Patients treated with BT showed a reduction in the use of montelukast and omalizumab 1 year after BT. CONCLUSION: In patients with severe persistent asthma and low asthma-related QOL scores, BT leads to an improvement in asthma-related QOL and a decrease in asthma medication use when measured 1 year after the final BT treatment.


Subject(s)
Asthma/surgery , Bronchial Thermoplasty , Quality of Life , Acetates/therapeutic use , Administration, Inhalation , Administration, Oral , Adrenal Cortex Hormones/therapeutic use , Adrenergic beta-Agonists/therapeutic use , Adult , Aged , Anti-Asthmatic Agents/therapeutic use , Asthma/drug therapy , Asthma/physiopathology , Asthma/psychology , Cholinergic Antagonists/therapeutic use , Cyclopropanes , Female , Forced Expiratory Volume , Humans , Male , Middle Aged , Omalizumab/therapeutic use , Prospective Studies , Quinolines/therapeutic use , Severity of Illness Index , Sulfides , Treatment Outcome , Vital Capacity
4.
J Evid Inf Soc Work ; 15(3): 243-257, 2018.
Article in English | MEDLINE | ID: mdl-29400637

ABSTRACT

OBJECTIVE: Hope is an important component to adolescents' mental health and well-being. While much study and theory have explored hope, few examine the idea within contextualized factors such as locale. Even fewer have sought to measure hope for urban adolescents. The Urban Adolescent Hope Scale (UAHS) was developed to measure hope in a contextualized manner as guided by previous qualitative inquiry. This study aims to establish initial validation for the UAHS. METHOD: Using findings from qualitative inquiry, a 24-item proposed measure of hope for urban adolescents was developed. Experts in various fields were consulted to provide face and content validity. The instrument was then given at school-wide needs assessment at an urban Midwestern high school. RESULTS: Using a confirmatory factor analysis, fit indices (RMSEA, TLI, CFI, and SRMR) and measures of internal consistency indicated a reliable five-factor structure of hope consisted of Spirituality (α = .936), Personal Agency (α = .930), The Basics (α = .936), Education (α = .921), and Caring Connections (α = .875). CONCLUSION: The findings from this study indicate the UAHS has initial validity and reliability to be used as a measure of hope for urban adolescents. Future implications for research and practice are provided.


Subject(s)
Hope , Surveys and Questionnaires/standards , Urban Population , Adolescent , Educational Status , Empathy , Factor Analysis, Statistical , Female , Humans , Male , Mental Health , Psychometrics , Racial Groups , Reproducibility of Results , Self Efficacy , Sex Factors , Socioeconomic Factors , Spirituality , United States
5.
Rehabil Nurs ; 42(3): 164-171, 2017.
Article in English | MEDLINE | ID: mdl-29244044

ABSTRACT

PURPOSE: Perceiving imminent safe patient handling and movement (SPH&M) dangers may reduce musculoskeletal (MSK) injuries for nurses in the workplace. The purpose of this study is to develop and validate the 17-item Safe Patient Handling Perception Scale (SPHPS) as an evaluation instrument assessing perceptual risk of MSK injury based on SPH&M knowledge, practice, and resource accessibility in the workplace. METHODS: Data were collected from a convenience sample (N = 117) of nursing employees at a Veteran Affairs Medical Center. Factor analysis identified three factors: knowledge, practice, and accessibility. FINDINGS: The SPHPS demonstrated high levels of reliability, supported by acceptable alpha scores (SPHM knowledge [α = .866], SPHM practices [α = .901], and access to SPHM resources [α = .855]), in addition to the relatively low standard error of measurement scores (SEM). CONCLUSION: The study outcomes suggest that the SPHPS is a valid and reliable tool that can measure participants' perceived risk factors for MSK injuries.


Subject(s)
Moving and Lifting Patients/psychology , Moving and Lifting Patients/standards , Perception , Psychometrics/standards , Adult , Factor Analysis, Statistical , Female , Humans , Middle Aged , Psychometrics/instrumentation , Rehabilitation Nursing/methods , Reproducibility of Results , Surveys and Questionnaires , United States , United States Department of Veterans Affairs/organization & administration , Validation Studies as Topic
6.
Front Psychol ; 8: 179, 2017.
Article in English | MEDLINE | ID: mdl-28270780

ABSTRACT

Students rarely practice math outside of school requirements, which we refer to as the "math-practice gap". This gap might be the reason why students struggle with math, making it urgent to develop means by which to address it. In the current paper, we propose that math apps offer a viable solution to the math-practice gap: Online apps can provide access to a large number of problems, tied to immediate feedback, and delivered in an engaging way. To substantiate this conversation, we looked at whether tablets are sufficiently engaging to motivate children's informal math practice. Our approach was to partner with education agencies via a community-based participatory research design. The three participating education agencies serve elementary-school students from low-SES communities, allowing us to look at tablet use by children who are unlikely to have extensive access to online math enrichment programs. At the same time, the agencies differed in several structural details, including whether our intervention took place during school time, after school, or during the summer. This allowed us to shed light on tablet feasibility under different organizational constraints. Our findings show that tablet-based math practice is engaging for young children, independent of the setting, the student's age, or the math concept that was tackled. At the same time, we found that student engagement was a function of the presence of caring adults to facilitate their online math practice.

7.
AIDS Care ; 29(11): 1458-1462, 2017 11.
Article in English | MEDLINE | ID: mdl-28335616

ABSTRACT

Stable housing is key to improving health outcomes for people living with HIV/AIDS. Though many formerly homeless HIV positive individuals reside in supportive housing, little research has examined biometric HIV health outcomes for residents of these programs. Through a community-based research partnership, this study analyzed secondary data from a Shelter Plus Care supportive housing program in Cincinnati, Ohio to examine the likelihood of participants achieving a healthy CD4 count (>500 cells/mm3) and viral suppression (viral load <200 copies/mL) while in supportive housing and to identify participant characteristics associated with these outcomes. The study sample was 86 participants who entered the program between 2008 and 2016, including 50 current residents and 36 exited participants. Participants' average length of stay in Shelter Plus Care was 35.2 months (range 3.2-108.1 months) during the study period. Bivariate analysis indicated statistically significant improvements on both outcome variables, with 45% of participants achieving a healthy CD4 count and 79% achieving viral suppression by program exit or most recent time point. Participants who had health insurance at intake and who had never been incarcerated were more likely to achieve viral suppression, and longer length of stay in the program was also positively associated with viral suppression. These results add to the literature on the relationship between housing conditions and HIV health outcomes by demonstrating that residence in supportive housing is associated with improvements in CD4 count and viral load for a sample of formerly homeless persons living with HIV/AIDS, two-thirds of whom had co-occurring physical health, mental health, or substance abuse problems. Further research collaborations should expand on these findings to examine the service packages that are associated with optimal HIV health outcomes for supportive housing residents.


Subject(s)
Anti-Retroviral Agents/therapeutic use , HIV Infections/drug therapy , Ill-Housed Persons/statistics & numerical data , Social Determinants of Health , Viral Load , Acquired Immunodeficiency Syndrome , Adult , CD4-Positive T-Lymphocytes , Female , HIV Infections/virology , Housing , Humans , Male , Mental Health , Public Housing , Substance-Related Disorders , Treatment Outcome
8.
Exp Lung Res ; 37(4): 227-38, 2011 May.
Article in English | MEDLINE | ID: mdl-21309737

ABSTRACT

Idiopathic interstitial pneumonias are a group of idiopathic interstitial lung diseases of which idiopathic pulmonary fibrosis (IPF) is the lesion of usual interstitial pneumonia. Although the pathogenic mechanisms remain incompletely understood, disease-specific changes in blood, a readily accessible biospecimen, have not been fully characterized. To identify biomarkers from blood and sera, the immune status of IPF patients and control subjects without structural lung disease was quantified by measuring cell surface markers, mRNA levels, and serum proteins. Statistically significant differences in cellular and molecular markers were observed between the 2 groups. The cytokine receptor IL-17RB was significantly higher in CD14+ peripheral blood mononuclear cells (PBMCs) from IPF patients, whereas expression of the chemokine receptor CXCR4 was lower. Gene expression analyses identified 18 differentially expressed genes out of 195 selected. Of these, EMR1, CCR3, UPAR, FCGR2A, OPN, CEACAM3, CD16a, CD18, CD11b, LTF, and LCN2 were up-regulated, whereas IL-17RB, IL-10, PDGFA, CD301/Clec10a, CD25/IL-2RA, IL-23p19, and IL-15 were down-regulated in IPF. Differentially regulated genes were in the functional areas of inflammation and cell signaling. Serum levels of UPAR and OPN were higher in IPF. These observations reveal significant differences in cell and molecular markers involved in monocyte/macrophage activation and migration, and suggest a role for IL-17RB in IPF.


Subject(s)
Idiopathic Pulmonary Fibrosis/pathology , Macrophages/pathology , Monocytes/pathology , Aged , Aged, 80 and over , Biomarkers/analysis , Cell Movement , Humans , Macrophage Activation , Macrophages/metabolism , Male , Middle Aged , Monocytes/metabolism , Receptors, Interleukin/physiology , Receptors, Interleukin-17
9.
Clin Med Res ; 7(1-2): 14-20, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19251584

ABSTRACT

OBJECTIVE: To determine the effect of inhaled corticosteroid (ICS) therapy on glucose control in adults with type 2 diabetes mellitus and coexisting asthma or chronic obstructive pulmonary disease (COPD). DESIGN: A prospective randomized, double-blind, double-dummy placebo-controlled, crossover investigation of inhaled steroids and oral leukotriene blockers. SETTING: A United States Department of Veterans Affairs Health Care System outpatient setting. PARTICIPANTS: Adults with type 2 diabetes and asthma or COPD. METHODS: Subjects (n=12) were randomized to receive either inhaled fluticasone propionate (440 microg twice daily) and oral placebo, or inhaled placebo and oral montelukast (10 mg/day). After 6 weeks, subjects were switched to the opposite therapy for 6 weeks. The primary outcome measure was the change in the percentage of glycosylated hemoglobin (%HbA1c) at 6 weeks relative to the baseline value. RESULTS: Ten patients completed the study. The difference between the mean within-subject changes in %HbA1c associated with 6-week periods of fluticasone and the mean changes associated with montelukast therapy was small but statistically significant (mean difference=0.25; P<0.025). Neither fluticasone nor oral montelukast therapy for 6 weeks led to a significantly different mean % HbA1c compared with the relevant baseline (mean differences=0.11 and -0.14, respectively). CONCLUSION: The absence of a clinically significant within-subject difference in the changes in %HbA1c associated with fluticasone versus oral montelukast therapy, or between either therapy or baseline does not warrant recommending changes in therapy for asthma or diabetes in patients with these co-morbid conditions. However, we suggest that clinicians carefully monitor blood glucose control when diabetic patients initiate ICS, especially with higher dosages.


Subject(s)
Adrenal Cortex Hormones/administration & dosage , Diabetes Complications/drug therapy , Diabetes Mellitus, Type 2/drug therapy , Glucose/metabolism , Pulmonary Disease, Chronic Obstructive/complications , Pulmonary Disease, Chronic Obstructive/drug therapy , Acetates/administration & dosage , Administration, Inhalation , Aged , Androstadienes/administration & dosage , Anti-Asthmatic Agents/administration & dosage , Bronchodilator Agents/administration & dosage , Cross-Over Studies , Cyclopropanes , Double-Blind Method , Fluticasone , Glycated Hemoglobin/metabolism , Humans , Male , Middle Aged , Placebos , Quinolines/administration & dosage , Sulfides , Treatment Outcome
10.
Exp Lung Res ; 34(10): 631-62, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19085563

ABSTRACT

Chronic obstructive pulmonary diseases (COPD) may increase air pollution-related mortality. The relationship of immune mechanisms to mortality caused by fine particulates in healthy and COPD populations is incompletely understood. The objective of this study was to determine whether fine particulates from a single biomass fuel alter stress and inflammation biomarkers in people with COPD. Healthy and COPD subjects were exposed to smoke in a controlled indoor setting. Immune responses were quantified by measuring cell surface marker expression with flow-cytometric analysis and mRNA levels with quantitative reverse transcriptase-polymerase chain reactions in whole blood before and after exposure. Preexposure COPD subjects had more leukocytes, mainly CD14(+) monocytes and neutrophils, but fewer CD3(+) T cells. Fifty-seven of 186 genes were differentially expressed between healthy and COPD subjects' peripheral blood mononuclear cells (PBMCs). Of these, only nuclear factor (NF)-kappa B1, TIMP-1, TIMP-2, and Duffy genes were up-regulated in COPD subjects. At 4 hours post smoke exposure, monocyte levels decreased only in healthy subjects. Fifteen genes, particular to inflammation, immune response, and cell-to-cell signaling, were differentially expressed in COPD subjects, versus 4 genes in healthy subjects. The authors observed significant differences in subjects' PBMCs, which may elucidate the adverse effects of air pollution particulates on people with COPD.


Subject(s)
Biomass , Particulate Matter/adverse effects , Pulmonary Disease, Chronic Obstructive/immunology , Smoke/adverse effects , Adult , Aged , Aged, 80 and over , Biomarkers , Cardiovascular Diseases/etiology , Flow Cytometry , Gene Expression Profiling , HLA-DR Antigens/analysis , Humans , Immunophenotyping , Lipopolysaccharide Receptors/analysis , Middle Aged , Pulmonary Disease, Chronic Obstructive/complications , Pulmonary Disease, Chronic Obstructive/metabolism , Reverse Transcriptase Polymerase Chain Reaction
11.
Am J Manag Care ; 14(3): 141-8, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18333706

ABSTRACT

OBJECTIVE: To test the effectiveness of a care coordination program for telephone counseling in raising referral and treatment rates for smoking cessation. STUDY DESIGN: A demonstration project implementing a smoking cessation care coordination program offering telephone counseling and medication management to patients referred from primary care. METHODS: The study was performed at 18 Veterans Health Administration (VA) sites in California. Participants were VA patients receiving primary care. We randomly allocated 10 of 18 sites to receive the Telephone Care Coordination Program, which included simple 2-click referral, proactive care coordination, medication management, and 5 follow-up telephone calls. Each patient received a 30- to 45-minute counseling session from the California Smokers' Helpline. Patients at control sites received usual care. RESULTS: During 10 months, we received 2965 referrals. We were unable to reach 1156 patients (39%), despite at least 3 attempts. We excluded 73 patients (3%), and 391 patients (13%) were not interested. We connected the remaining 1345 patients (45%) to the Helpline. At 6-month followup, 335 patients (11% of all referrals and 25% of participating patients) were abstinent. Providers at intervention sites reported referring many more patients to telephone counseling than providers at control sites (15.6 vs 0.7 in the prior month). CONCLUSIONS: The program generated a large number of referrals; almost half of the patients referred were connected with the Helpline. Long-term abstinence was excellent. These results suggest that managed care organizations may be able to improve tobacco control by implementing a similar system of care coordination.


Subject(s)
Counseling , Managed Care Programs/organization & administration , Referral and Consultation/statistics & numerical data , Smoking Cessation/methods , California/epidemiology , Female , Hospitals, Veterans , Humans , Logistic Models , Male , Managed Care Programs/statistics & numerical data , Middle Aged , Smoking/epidemiology , Smoking/psychology , Social Class , Telephone
12.
Article in English | MEDLINE | ID: mdl-17674008

ABSTRACT

Predatory fish sometimes capture a prey fish first by striking it from the side, allowing the predator to consume the stunned prey head first. The rapid body flexion that the predator uses to stun its prey is similar to the "C" shaped maneuver ("C-bend") that many fish species use when performing a C-start escape response. For most species, one of the two Mauthner neurons initiates the C-start and, together with other reticulospinal neurons, their activity determines the extent of the bend and the ultimate trajectory of the fish. Reported here is initial evidence of previously undescribed behaviors where goldfish strike an object while executing voluntary C-bends that are similar to their C-start escape responses. The overlapping distributions of turn durations, turn angles, and angular velocities suggest that at least some voluntary C-bends are initiated by the Mauthner neuron. This implies that the Mauthner neuron can be activated voluntarily in the absence of predator- or feeding-associated releasing stimuli.


Subject(s)
Goldfish/physiology , Motor Activity/physiology , Motor Neurons/physiology , Predatory Behavior/physiology , Animals , Escape Reaction/physiology , Video Recording
13.
J Neurosci Methods ; 158(1): 19-21, 2006 Nov 15.
Article in English | MEDLINE | ID: mdl-16782203

ABSTRACT

It is sometimes useful in electrophysiological recordings to try various micropipette profiles in order to determine which tip works best in a given experiment. A pipette puller can be used to pull very sharp or blunt pipettes, and to fire polish tips for whole cell patch recordings. Broken tip pipettes can be "bumped" to an acceptable tip diameter under a microscope. However, it may be difficult to rationalize the purchase of a commercial beveling machine simply to test whether beveled pipettes are best for recording intracellularly from the cell types of interest. Presented here are methods that use a surplus computer hard drive to reproducibly dry bevel glass micropipettes. Compared to sharp or broken tip electrodes, pipettes dry beveled with this simple system are superior for making intracellular recordings from cichlid Mauthner neurons. Preliminary data obtained with this inexpensive apparatus may allow investigators to successfully justify the purchase of a commercial beveler.


Subject(s)
Computers , Microelectrodes , Neurophysiology/instrumentation , Patch-Clamp Techniques/instrumentation , Animals , Glass
14.
Brain Behav Evol ; 67(4): 188-202, 2006.
Article in English | MEDLINE | ID: mdl-16493194

ABSTRACT

When startled by sound, goldfish make large turns away from a rostral stimulus and small responses away from caudal stimuli, suggesting that rostral startling stimuli recruit larger pools of reticulospinal neurons in the Brainstem Escape Network (BEN) than do caudal stimuli. Consistent with this idea, the zebrafish Mauthner (M-) cell fires when the fish is startled by tail-directed stimuli, but the M-cell homologues (MiD2cm and MiD3cm) are also recruited when the fish is startled by displacing the head. Because vision is known to modulate M-cell activity, a nonstartling, modulatory sensory 'signal' conveyed to the reticular formation may be stronger if the visual sensory image is from a rostral vs. caudal spatial location and could account for a differential neuron pool recruitment and response magnitude. In this study, electrophysiological recordings from cichlid Mauthner neurons showed that visual stimulation of the caudal retina (by a rostral cue) generates a depolarization that is about 1.5 times the amplitude of that generated by stimulation of the rostral retina (by a caudal cue). In behavioral testing, where fish were stimulated visually for 30 ms and then startled by sound, fish startled in the presence of a rostral visual stimulus performed larger amplitude and faster turns than when startled in the presence of a caudal visual stimulus. Thus, M-cell potentials might reflect the strength of visual input to the BEN in general. For a particular visual spatial location, the relative strength of descending visual input appears to contribute to a recruitment of a reticulospinal neuron population that generates a turn magnitude appropriate to the visual cue, and suggests that a retinotopic representation is preserved in the BEN.


Subject(s)
Brain/physiology , Neurons/physiology , Space Perception/physiology , Visual Perception/physiology , Animals , Goldfish , Ocular Physiological Phenomena
15.
Integr Comp Biol ; 45(3): 547-54, 2005 Jun.
Article in English | MEDLINE | ID: mdl-21676800

ABSTRACT

The ability to process in parallel multiple forms of sensory information, and link sensory-sensory associations to behavior, presumably allows for the opportunistic use of the most reliable and predictive sensory modalities in diverse behavioral contexts. Evolutionary considerations indicate that such processing may represent a fundamental operating principle underlying complex sensory associations and sensory-motor integration. Here, we suggest that animal navigation is a particularly useful model of such opportunistic use of sensory and motor information because it is possible to study directly the effects of memory on neural system functions. First, comparative evidence for parallel processing across multiple brain structures during navigation is provided from the literatures on fish and rodent navigation. Then, based on neurophysiological evidence of coordinated, multiregional processing, we provide a neurobiological explanation of learning and memory effects on neural circuitry mediating navigation.

16.
J Neurosci Methods ; 133(1-2): 127-34, 2004 Feb 15.
Article in English | MEDLINE | ID: mdl-14757353

ABSTRACT

We have adapted for use in fish several of the procedures employed for recording single neuron activity in freely behaving rodents. Developing a method for single unit chronic recording in freely behaving fish was motivated by a need for a comparison across taxa of telencephalic neural activity evoked during spatial navigation by animals of their environments. However, the procedures outlined here can be modified easily for underwater recording from most aquatic species and from other brain areas. Under anesthesia, bundles of stereotrodes or tetrodes were implanted into the dorsolateral region of the goldfish or cichlid telencephalon. An infrared light emitting diode (LED) was also fixed to the fish's head at the time of surgery. After recovery from anesthesia, fish were allowed to swim freely within a large aquarium. Single unit activity was analyzed and correlated with stimulus conditions, behavior, and the location and movement of the LED recorded by a camera tracking system. The value of this technique is demonstrated by providing the first evidence in fish for navigation-related neural firing, including "place cells" that display location-specific discharge.


Subject(s)
Behavior, Animal/physiology , Electrophysiology/methods , Neurons/physiology , Telencephalon/physiology , Action Potentials , Animals , Brain Mapping , Cichlids/physiology , Electrodes, Implanted , Goldfish/physiology , Neurons/classification , Staining and Labeling , Telencephalon/cytology
17.
Brain Behav Evol ; 61(3): 148-58, 2003.
Article in English | MEDLINE | ID: mdl-12697956

ABSTRACT

To study the modulatory influences of visual information on Mauthner (M-) initiated C-start responses, short interval visual stimuli were presented to individual cichlid fish prior to being startled with a sound pulse. Because the axon of each Mauthner neuron activates trunk musculature contralateral to the soma, the initial direction of an ensuing startle response provides a behavioral measure of which cell has been driven closer to threshold by visual cues at the time the sound pulse causes one cell to fire. When an LED was illuminated on one side of the fish for 10 ms prior to a startling sound pulse, cichlids reliably turned toward the visual cue. At durations of 15 and 20 ms, fish turned away from the same stimulus. Thus, behavioral evidence suggests that the M-cell contralateral to a visual stimulus appears to be excited first but visual excitation of the M-cell ipsilateral to the visual stimulus follows and predominates. Consistent with the behavioral results, visually evoked excitatory potentials recorded intracellularly in the cichlid M-cells were complex, with initial PSPs showing latencies of about 11.6 ms from contralateral eye stimulation and 15.5 ms from stimulating the ipsilateral eye. PSP latencies in goldfish were longer and more similar for stimuli to the two eyes (about 22 ms). For contrast, sound-evoked PSPs begin within 2 ms. The relative long latencies for visually regulating M-cell function suggest that vision is most adaptive for biasing response direction prior to rather than during a predator's attack.


Subject(s)
Goldfish/physiology , Reflex, Startle/physiology , Acoustic Stimulation , Animals , Cues , Electric Stimulation , Excitatory Postsynaptic Potentials/physiology , Female , Male , Photic Stimulation , Sound Localization , Superior Colliculi/physiology
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