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1.
Glob Public Health ; 19(1): 2346947, 2024 Jan.
Article En | MEDLINE | ID: mdl-38718290

Young people in Colombia present high rates of mental health problems, to which the country's history of armed internal conflict contributes in complex ways. Mental health services in Colombia are fragmented, inadequate, and difficult to access for many. Young people's help-seeking is often hindered by mental health stigma and/or poor experiences with services. This paper presents a thematic analysis of qualitative data from a mixed-methods study aimed at developing and testing a mental health intervention for Colombian youths. We draw upon theoretical lenses from scholarly work on stigma and Sen's 'capabilities approach' to inform our analysis of interviews and group discussions with staff and young people involved in the state-funded human capital building programme 'Jovenes en Acción' (JeA). By illustrating how study participants talked about stigma, vulnerability, mental health services organisation, and the challenges of discussing mental health topics in a learning environment, we illuminate aspects of mental health support and anti-stigma interventions that might need enhancing. In particular, we suggest that more emphasis on 'community competencies' as complementary to and interrelated with individual competencies would strengthen young people's individual and collective resources for mental wellbeing while being in line with the sociocritical principles of existing human capital-enhancing programmes.


Interviews as Topic , Mental Health Services , Qualitative Research , Social Stigma , Humans , Colombia , Adolescent , Female , Male , Young Adult , Armed Conflicts , Mental Health , Mental Disorders
2.
Front Psychiatry ; 14: 1238725, 2023.
Article En | MEDLINE | ID: mdl-38034913

Background: Colombia has endured more than five decades of internal armed conflict, which led to substantial costs for human capital and mental health. There is currently little evidence about the impact of incorporating a mental health intervention within an existing public cash transfer program to address poverty, and this project aims to develop and pilot a mental health support intervention embedded within the human capital program to achieve better outcomes among beneficiaries, especially those displaced by conflict and the most socioeconomically vulnerable. Methods: The study will consist of three phases: semi-structured one-to-one interviews, co-design and adaptations of the proposed intervention with participants and pilot of the digital intervention based on cognitive behavioral therapy and transdiagnostic techniques to determine its feasibility, acceptability, efficacy, and usefulness in 'real settings'. Results will inform if the intervention improves clinical, educational and employment prospects among those who use it. Results: Knowledge will be generated on whether the mental health intervention could potentially improve young people's mental health and human capital in conflict-affected areas? We will evaluate of the impact of potential mental health improvements on human capital outcomes, including educational and employment outcomes. Conclusion: Findings will help to make conclusions about the feasibility and acceptability of the intervention, and it will assess its effectiveness to improve the mental health and human capital outcomes of beneficiaries. This will enable the identification of strategies to address mental health problems among socioeconomically vulnerable young people that can be adapted to different contexts in in low and middle-income countries.

3.
JAMA Psychiatry ; 80(10): 991-999, 2023 10 01.
Article En | MEDLINE | ID: mdl-37466983

Importance: A transdiagnostic treatment, the Unified Protocol, is as effective as single diagnostic protocols in comorbid emotional disorders in clinical populations. However, its effects on posttraumatic stress disorder and other emotional disorders in individuals living in war and armed conflict contexts have not been studied. Objective: To evaluate the efficacy of a cultural and contextual adaptation of the Unified Protocol (CXA-UP) on posttraumatic stress disorder, anxiety, and depression compared to waitlist control in individuals exposed to armed conflict in Colombia. Design, Setting, and Participants: From April 2017 to March 2020, 200 participants 18 years and older were randomly assigned to the CXA-UP or to a waitlist condition. CXA-UP consisted of 12 to 14 twice-a-week or weekly individual 90-minute face-to-face sessions. Outcomes were assessed at baseline, posttreatment, and 3 months following treatment. Analyses were performed and compared for all randomly allocated participants (intent-to-treat [ITT]) and for participants who completed all sessions and posttreatment measures (per protocol [PP]). The study took place at an outpatient university center and included individuals who were registered in the Colombian Victims Unit meeting DSM-5 diagnostic criteria for posttraumatic stress disorder, anxiety, or depression or were severely impaired by anxiety or depression. Individuals who were receiving psychological therapy, were dependent on alcohol or drugs, were actively suicidal or had attempted suicide in the previous 2 months, had psychosis or bipolar disorder, or were cognitively impaired were excluded. Intervention: CXA-UP or waitlist. Main Outcomes and Measures: Primary outcomes were changes in anxiety, depression, and somatic scores on the Patient Health Questionnaire and Posttraumatic Stress Disorder Checklist for DSM-5. Results: Among the 200 participants (160 women [80.0%]; 40 men [20.0%]; mean [SD] age, 43.1 [11.9] years), 120 were randomized to treatment and 80 to waitlist. Results for primary outcomes in the ITT analysis showed a significant pretreatment-to-posttreatment reduction when comparing treatment and waitlist on the posttraumatic stress disorder checklist for DSM-5 scores (slope [SE], -31.12 [3.00]; P < .001; Cohen d, 0.90; 90% CI, 0.63-1.19), 9-item Patient Health Questionnaire (PHQ-9) (slope [SE],-11.94 [1.30]; P < .001; Cohen d, 0.77; 90% CI, 0.52-1.06), PHQ-anxiety (slope [SE], -6.52 [0.67]; P < .001; Cohen d, 0.82; 90% CI, 0.49-1.15), and PHQ-somatic (slope [SE], -8.31 [0.92]; P < .001; Cohen d, 0.75; 90% CI, 0.47-1.04). Conclusions and Relevance: In this study, significant reductions and large effect sizes in all measures of different emotional disorders showed efficacy of a single transdiagnostic intervention in individuals exposed to armed conflicts. Trial Registration: ClinicalTrials.gov Identifier: NCT03127982.


Anxiety Disorders , Stress Disorders, Post-Traumatic , Male , Humans , Female , Adult , Colombia , Anxiety Disorders/therapy , Stress Disorders, Post-Traumatic/diagnosis , Stress Disorders, Post-Traumatic/therapy , Stress Disorders, Post-Traumatic/psychology , Anxiety/diagnosis , Anxiety/therapy , Armed Conflicts , Treatment Outcome
5.
J Acoust Soc Am ; 142(4): 2073, 2017 10.
Article En | MEDLINE | ID: mdl-29092534

Vowels are complex sounds with four to five spectral peaks known as formants. The frequencies of the two lowest formants, F1and F2, are sufficient for vowel discrimination. Behavioral studies show that many birds and mammals can discriminate vowels. However, few studies have quantified thresholds for formant-frequency discrimination. The present study examined formant-frequency discrimination in budgerigars (Melopsittacus undulatus) and humans using stimuli with one or two formants and a constant fundamental frequency of 200 Hz. Stimuli had spectral envelopes similar to natural speech and were presented with random level variation. Thresholds were estimated for frequency discrimination of F1, F2, and simultaneous F1 and F2 changes. The same two-down, one-up tracking procedure and single-interval, two-alternative task were used for both species. Formant-frequency discrimination thresholds were as sensitive in budgerigars as in humans and followed the same patterns across all conditions. Thresholds expressed as percent frequency difference were higher for F1 than for F2, and were unchanged between stimuli with one or two formants. Thresholds for simultaneous F1 and F2 changes indicated that discrimination was based on combined information from both formant regions. Results were consistent with previous human studies and show that budgerigars provide an exceptionally sensitive animal model of vowel feature discrimination.


Behavior, Animal , Discrimination, Psychological , Melopsittacus , Pitch Discrimination , Speech Acoustics , Speech Perception , Voice Quality , Acoustic Stimulation , Adult , Animals , Audiometry, Pure-Tone , Auditory Threshold , Female , Humans , Male , Psychoacoustics , Species Specificity , Young Adult
6.
J Assoc Res Otolaryngol ; 18(1): 165-181, 2017 Feb.
Article En | MEDLINE | ID: mdl-27766433

Vowels make a strong contribution to speech perception under natural conditions. Vowels are encoded in the auditory nerve primarily through neural synchrony to temporal fine structure and to envelope fluctuations rather than through average discharge rate. Neural synchrony is thought to contribute less to vowel coding in central auditory nuclei, consistent with more limited synchronization to fine structure and the emergence of average-rate coding of envelope fluctuations. However, this hypothesis is largely unexplored, especially in background noise. The present study examined coding mechanisms at the level of the midbrain that support behavioral sensitivity to simple vowel-like sounds using neurophysiological recordings and matched behavioral experiments in the budgerigar. Stimuli were harmonic tone complexes with energy concentrated at one spectral peak, or formant frequency, presented in quiet and in noise. Behavioral thresholds for formant-frequency discrimination decreased with increasing amplitude of stimulus envelope fluctuations, increased in noise, and were similar between budgerigars and humans. Multiunit recordings in awake birds showed that the midbrain encodes vowel-like sounds both through response synchrony to envelope structure and through average rate. Whereas neural discrimination thresholds based on either coding scheme were sufficient to support behavioral thresholds in quiet, only synchrony-based neural thresholds could account for behavioral thresholds in background noise. These results reveal an incomplete transformation to average-rate coding of vowel-like sounds in the midbrain. Model simulations suggest that this transformation emerges due to modulation tuning, which is shared between birds and mammals. Furthermore, the results underscore the behavioral relevance of envelope synchrony in the midbrain for detection of small differences in vowel formant frequency under real-world listening conditions.


Auditory Threshold , Mesencephalon/physiology , Noise , Sound , Adult , Animals , Cochlear Nerve/physiology , Female , Humans , Male , Melopsittacus
7.
J Neurophysiol ; 115(4): 1905-16, 2016 Apr.
Article En | MEDLINE | ID: mdl-26843608

Amplitude modulation (AM) is a crucial feature of many communication signals, including speech. Whereas average discharge rates in the auditory midbrain correlate with behavioral AM sensitivity in rabbits, the neural bases of AM sensitivity in species with human-like behavioral acuity are unexplored. Here, we used parallel behavioral and neurophysiological experiments to explore the neural (midbrain) bases of AM perception in an avian speech mimic, the budgerigar (Melopsittacus undulatus). Behavioral AM sensitivity was quantified using operant conditioning procedures. Neural AM sensitivity was studied using chronically implanted microelectrodes in awake, unrestrained birds. Average discharge rates of multiunit recording sites in the budgerigar midbrain were insufficient to explain behavioral sensitivity to modulation frequencies <100 Hz for both tone- and noise-carrier stimuli, even with optimal pooling of information across recording sites. Neural envelope synchrony, in contrast, could explain behavioral performance for both carrier types across the full range of modulation frequencies studied (16-512 Hz). The results suggest that envelope synchrony in the budgerigar midbrain may underlie behavioral sensitivity to AM. Behavioral AM sensitivity based on synchrony in the budgerigar, which contrasts with rate-correlated behavioral performance in rabbits, raises the possibility that envelope synchrony, rather than average discharge rate, might also underlie AM perception in other species with sensitive AM detection abilities, including humans. These results highlight the importance of synchrony coding of envelope structure in the inferior colliculus. Furthermore, they underscore potential benefits of devices (e.g., midbrain implants) that evoke robust neural synchrony.


Mesencephalon/physiology , Vocalization, Animal , Action Potentials , Animals , Conditioning, Operant , Melopsittacus
8.
Cogn Behav Pract ; 22(3): 302-316, 2015 Aug 01.
Article En | MEDLINE | ID: mdl-26120268

Given the enormous individual, familial, and societal costs associated with early disruptive behavior disorders, transformative efforts are needed to develop innovative options for overcoming traditional barriers to effective care and for broadening the availability of supported interventions. This paper presents the rationale and key considerations for a promising innovation in the treatment of early-onset disruptive behavior disorders-that is, the development of an Internet-based format for the delivery of Parent-Child Interaction Therapy (PCIT) directly to families in their own homes. Specifically, we consider traditional barriers to effective care, and discuss how technological innovations can overcome problems of treatment availability, accessibility, and acceptability. We then detail our current Internet-delivered PCIT treatment program (I-PCIT), which is currently being evaluated across multiple randomized clinical trials relative to waitlist comparison, and to traditional in-office PCIT. Embedded video clips of children treated with I-PCIT are used to illustrate novel aspects of the treatment.

9.
J Assoc Res Otolaryngol ; 16(2): 255-62, 2015 Apr.
Article En | MEDLINE | ID: mdl-25595542

The acoustical cues and physiological processing mechanisms underlying the perception of the distance of sound sources are not well understood. To understand the relation between physiology and behavior, a first step is to use an animal model to study distance sensitivity. The goal of these experiments was to establish the capacity of the Dutch-belted rabbit to discriminate between sound sources at two distances. Trains of noise bursts were presented from speakers that were located either directly in front of the rabbit or at a 45 ° angle in azimuth. The reference speaker was positioned at distances of 20, 40, and 60 cm from the subject, and the more distant test speaker was systematically moved to determine the smallest difference in distance that could be reliably discriminated by the subject. Noise stimuli had one of three bandwidths: wideband (0.1-10 kHz), low-pass (0.1-3 kHz), or high-pass (3-10 kHz). The mean stimulus level was 60 dB sound pressure level (SPL) at the location of the rabbit's head, and the level was roved over a 12-dB range from trial to trial to reduce the availability of level cues. An operant one-interval two-alternative non-forced choice task was used, with a blocked two-down-one-up tracking procedure to determine the distance discriminability. Rabbits were consistently able to discriminate two distances when they were sufficiently separated. Sensitivity was better when the reference distance was 60 cm at either azimuth (distance ratio = 1.5) and was worse when the reference distance was 20 cm (distance ratio = 2.4 at 0 ° and 1.75 at 45 °).


Sound Localization/physiology , Animals , Auditory Threshold , Discrimination, Psychological , Female , Noise , Rabbits
10.
J Neurosci ; 34(4): 1306-13, 2014 Jan 22.
Article En | MEDLINE | ID: mdl-24453321

Establishing neural determinants of psychophysical performance requires both behavioral and neurophysiological metrics amenable to correlative analyses. It is often assumed that organisms use neural information optimally, such that any information available in a neural code that could improve behavioral performance is used. Studies have shown that detection of amplitude-modulated (AM) auditory tones by humans is correlated to neural synchrony thresholds, as recorded in rabbit at the level of the inferior colliculus, the first level of the ascending auditory pathway where neurons are tuned to AM stimuli. Behavioral thresholds in rabbit, however, are ∼10 dB higher (i.e., 3 times less sensitive) than in humans, and are better correlated to rate-based than temporal coding schemes in the auditory midbrain. The behavioral and physiological results shown here illustrate an unexpected, suboptimal utilization of available neural information that could provide new insights into the mechanisms that link neuronal function to behavior.


Auditory Perception/physiology , Auditory Threshold/physiology , Behavior, Animal/physiology , Neurons/physiology , Acoustic Stimulation , Adult , Animals , Female , Humans , Middle Aged , Rabbits , Young Adult
11.
Adv Exp Med Biol ; 787: 391-8, 2013.
Article En | MEDLINE | ID: mdl-23716245

Envelope fluctuations of complex sounds carry information that is -essential for many types of discrimination and for detection in noise. To study the neural representation of envelope information and mechanisms for processing of this temporal aspect of sounds, it is useful to identify an animal model that can -sensitively detect amplitude modulations (AM). Low modulation frequencies, which dominate speech sounds, are of particular interest. Yet, most animal -models studied previously are relatively insensitive to AM at low modulation -frequencies. Rabbits have high thresholds for low-frequency modulations, -especially for tone carriers. Rhesus macaques are less sensitive than humans to low-frequency -modulations of wideband noise (O'Conner et al. Hear Res 277, 37-43, 2011). Rats and -chinchilla also have higher thresholds than humans for amplitude -modulations of noise (Kelly et al. J Comp Psychol 120, 98-105, 2006; Henderson et al. J Acoust Soc Am 75, -1177-1183, 1984). In contrast, the budgerigar has thresholds for AM detection of wideband noise similar to those of human listeners at low -modulation frequencies (Dooling and Searcy. Percept Psychophys 46, 65-71, 1981). A -one-interval, two-alternative operant conditioning procedure was used to estimate AM -detection thresholds for 4-kHz tone carriers at low modulation -frequencies (4-256 Hz). Budgerigar thresholds are comparable to those of human subjects in a comparable task. Implications of these comparative results for temporal coding of complex sounds are discussed. Comparative results for masked AM detection are also presented.


Auditory Threshold/physiology , Melopsittacus/physiology , Models, Animal , Animals , Conditioning, Psychological/physiology , Cues , Humans , Loudness Perception/physiology , Noise , Perceptual Masking/physiology , Pitch Perception/physiology , Psychoacoustics , Rabbits , Species Specificity , Time Perception/physiology
12.
Hear Res ; 275(1-2): 89-95, 2011 May.
Article En | MEDLINE | ID: mdl-21147208

The characterization of ability in behavioral sound-localization tasks is an important aspect of understanding how the brain encodes and processes sound location information. In a few species, both physiological and behavioral results related to sound localization are available. In the Mongolian gerbil, physiological sensitivity to interaural time differences in the auditory brainstem is comparable to that reported in other species; however, the gerbil has been reported to have relatively poor behavioral localization performance as compared with several other species. In this study, the behavioral performance of the gerbil for sound localization was re-examined using a task that involved a simpler response map than in previously published studies. In the current task, the animal directly approached the speaker on each trial, thus the response map was simpler than the 90°-right vs. 90°-left response required in previous studies of localization and source discrimination. Although the general performance across a group of animals was more consistent in the task with the simpler response map, the sound-localization ability replicated that previously reported. These results are consistent with the previous reports that sound-localization performance in gerbil is poor with respect to other species that have comparable neural sensitivity to interaural cues.


Gerbillinae/physiology , Sound Localization/physiology , Acoustic Stimulation/methods , Animals , Auditory Pathways , Auditory Threshold/physiology , Behavior, Animal , Brain Stem , Equipment Design , Female , Male , Models, Biological , Neurons/metabolism , Psychoacoustics , Sound
13.
J Assoc Res Otolaryngol ; 8(4): 522-38, 2007 Dec.
Article En | MEDLINE | ID: mdl-17899269

Processing mechanisms used for detection of tones in noise can be revealed by using reproducible noise maskers and analyzing the pattern of results across masker waveforms. This study reports detection of a 500-Hz tone in broadband reproducible noise by rabbits using a set of masker waveforms for which human results are available. An appetitive-reinforcement, operant-conditioning procedure with bias control was used. Both fixed-level and roving-level noises were used to explore the utility of energy-related cues for detection. An energy-based detection model was able to partially explain the fixed-level results across reproducible noise waveforms for both rabbit and human. A multiple-channel energy model was able to explain fixed-level results, as well as the robust performance observed with roving-level noises. Further analysis using the energy model indicated a difference between species: human detection was influenced most by the noise spectrum surrounding the tone frequency, whereas rabbit detection was influenced most by the noise spectrum at frequencies above that of the tone. In addition, a temporal envelope-based model predicted detection by humans as well as the single-channel energy model did, but the envelope-based model failed to predict detection by rabbits. This result indicates that the contributions of energy and temporal cues to auditory processing differ across species. Overall, these findings suggest that caution must be used when evaluating neural encoding mechanisms in one species on the basis of behavioral results in another.


Noise , Perceptual Masking/physiology , Pitch Discrimination/physiology , Acoustic Stimulation , Animals , Bias , Conditioning, Operant , Female , Humans , Rabbits , Species Specificity
14.
Q J Exp Psychol B ; 56(2): 193-205, 2003 May.
Article En | MEDLINE | ID: mdl-12791568

Experimental studies were performed using a Pavlovian-conditioned eyeblink response to measure detection of a variable-sound-level tone (T) in a fixed-sound-level masking noise (N) in rabbits. Results showed an increase in the asymptotic probability of conditioned responses (CRs) to the reinforced TN trials and a decrease in the asymptotic rate of eyeblink responses to the non-reinforced N presentations as a function of the sound level of the T. These observations are consistent with expected behaviour in an auditory masked detection task, but they are not consistent with predictions from a traditional application of the Rescorla-Wagner or Pearce models of associative learning. To implement these models, one typically considers only the actual stimuli and reinforcement on each trial. We found that by considering perceptual interactions and concepts from signal detection theory, these models could predict the CS dependence on the sound level of the T. In these alternative implementations, the animals response probabilities were used as a guide in making assumptions about the "effective stimuli".


Auditory Perception , Conditioning, Classical/physiology , Perceptual Masking , Animals , Blinking , Models, Psychological , Probability , Rabbits
15.
J Acoust Soc Am ; 111(1 Pt 1): 346-56, 2002 Jan.
Article En | MEDLINE | ID: mdl-11831807

Binaural detection with narrowband and wideband noise maskers was examined by using a Pavlovian-conditioned eyeblink response in rabbits. The target was a tone at 500 Hz, and the maskers were ten individual noise samples having one of two bandwidths, 200 Hz (410 Hz to 610 Hz) or 2900 Hz (100 Hz to 3 kHz). The narrowband noise maskers were created by filtering the wideband noise maskers such that the two sets of maskers had identical spectra in the 200-Hz frequency region surrounding the tone. The responses across the set of noise maskers were compared across bandwidths and across interaural configurations (N0S0 and N0S(pi)). Responses across the set of noise waveforms were not strongly correlated across bandwidths; this result is inconsistent with models for binaural detection that depend only upon the narrow band of energy centered at the frequency of the target tone. Responses were correlated across interaural configurations for the wideband masker condition, but not for the narrowband masker. All of these results were consistent with the companion study of human listeners [Evilsizer et al., J. Acoust. Soc. Am. 111, 336-345 (2002)] and with the results of human studies of binaural detection that used only wideband [Gilkey et al., J. Acoust. Soc. Am. 78, 1207-1219 (1985)] or narrowband [Isabelle and Colburn, J. Acoust. Soc. Am. 89, 352-259 (1991)] individual noise maskers.


Auditory Perception/physiology , Noise/adverse effects , Perceptual Masking/physiology , Animals , Blinking/physiology , Conditioning, Classical/physiology , Psychoacoustics , Psychophysics , Rabbits , Reproducibility of Results
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