How Old Do You Think I Am? Speech-Language Predictors of Perceived Age and Communicative Competence.

Purpose Spoken language serves as a primary means of social interaction, but speech and language skills change with age, a potential source of age-related stereotyping. The goals of this study were to examine how accurately age could be estimated from language samples, to determine which speech and language cues were most informative, and to assess the impact of perceived age on judgments of the speakers' communication skills. Method We analyzed narratives from 84 speakers aged 30-89 years to identify age-related differences and compared these differences to factors affecting perceptions of age and communicative competence. Three groups of raters estimated the speakers' ages and judged the quality of their communication: 44 listeners listened to audio-recorded narratives, 51 readers read transcripts of the narratives, and 24 voice raters listened to 10-s samples of speech extracted from one of the narratives. Results Older speakers spoke more slowly but showed minimal linguistic differences compared to younger speakers. Speakers' ages were estimated quite accurately, even from 10-s samples. Estimates were largely based on cues available in the acoustic signal-speech rate and vocal characteristics-so listeners were more accurate than readers. However, an overreliance on these cues also contributed to overestimates of speakers' ages. Communication ratings were not strongly related to perceived age but were influenced by various aspects of speech and language. In particular, speakers who produced longer narratives and spoke more quickly were judged to be better communicators. Conclusion Speakers tend to be judged on relatively superficial aspects of spoken language, in part because age-related change is most evident at these levels. Implications of these findings for age-related theories of stereotyping and speech-language intervention are discussed.

The Distribution and Severity of Tremor in Speech Structures of Persons with Vocal Tremor.

BACKGROUND: Vocal tremor may be associated with cyclic oscillations in the pulmonary, laryngeal, velopharyngeal, or oral regions. OBJECTIVES: This study aimed to correlate the overall severity of vocal tremor with the distribution and severity of tremor in structures involved. METHODS: Endoscopic and clinical examinations were completed on 20 adults with vocal tremor and two age-matched controls during sustained phonation. Two judges rated the severity of vocal tremor and the severity of tremor affecting each of 13 structures. RESULTS: Participants with mild vocal tremor typically presented with tremor in three laryngeal structures, moderate vocal tremor in five structures (laryngeal and another region), and severe vocal tremor in eight structures affecting all regions. The severity of tremor was lowest (mean = 1.2 out of 3) in persons with mild vocal tremor and greater in persons with moderate (mean = 1.5) and severe vocal tremor (mean = 1.4). Laryngeal structures were most frequently (95%) and severely (1.7 out of 3) affected, followed by velopharynx (40% occurrence, 1.3 severity), pulmonary (40% occurrence, 1.1 severity), and oral (40% occurrence, 1.0 severity) regions. Regression analyses indicated tremor severity of the supraglottic structures, and vertical laryngeal movement contributed most to vocal tremor severity during sustained phonation (r = 0.77, F = 16.17, P < 0.0001). A strong positive correlation (r = 0.72) was found between the Tremor Index and the severity of the vocal tremor during sustained phonation. CONCLUSION: It is useful to obtain a wide endoscopic view of the larynx to visualize tremor, which is rarely isolated to the true vocal folds alone.

Exploring Client and Therapist Experiences of Sexual Offender Intervention: Developing a Model of "Significant Events".

This research explored the therapeutic events both clients and therapists from community-based treatment interventions for perpetrators of sexual abuse identify as significant in their experience of psychological therapy. A qualitative design was utilized to address this research objective. The sample for the present research is comprised of three different treatment programs for sexual offending. Twenty-five clients and nine therapists participated in the study. Two qualitative measures were used to elicit client and therapist responses. Significant Aspects of Therapy Form was administered every second treatment session during each intervention program. The Significant Aspects Follow-Up Interview was conducted with a sub-sample of participants at the conclusion of each treatment module. Thematic analysis was used to identify significant themes noted by clients and therapists from forms and interviews. Thematic analysis resulted in a model of significant events in therapy. In this model, significant events were categorized into six domains. The six domains were as follows: (a) the process of therapy, (b) making changes and progress in therapy, (c) content and structure of therapy, (d) therapist contributions, (e) negative contributions to therapy, and (f) other factors Each domain further contained between 6 and 18 themes, which are also reported. This study found much overlap and similarity in the experiences of therapy between clients of sexual offender therapy and general psychotherapy. Furthermore, there is overlap between therapists and clients in the aspects of therapy they identify as significant. The implications of these findings on effective service development and comprehensive service evaluations are discussed.

The effects of articulation on the perceived loudness of the projected voice.

UNLABELLED: Arthur Lessac developed a voice training approach that concentrated on three energies: structural action, tonal action, and consonant action. In Lessac-Madsen Resonant Voice Therapy (LMRVT), speech-language pathologists help patients achieve a resonant voice through structural posturing and awareness of tonal changes. However, LMRVT many not necessarily include the third component of Lessac's approach: consonant action.This study examines the effect that increased effort on consonant production has on the speaking voice-particularly regarding vocal loudness and projection. METHODS: Audio samples were collected from eight actor participants who read a monologue using three distinct styles: normal articulation, poor articulation (elicited using a bite block), and overarticulation (elicited using a Lessac-based training intervention). Twenty graduate students of speech-language pathology listened to speech samples from the different conditions and made comparative judgments regarding articulation, loudness, and projection. RESULTS: Group results showed a strong correlation between the articulatory condition and the level of perceived loudness and projection. That is, as precision of articulation increased, the ratings of perceived loudness and projection increased, as well. CONCLUSIONS: These findings indicate that articulation treatment may have a positive influence on the perception of vocal loudness and projection. This has implications for future directions in expanding voice therapy modalities.

Cricothyroid muscle and thyroarytenoid muscle dominance in vocal register control: preliminary results.

HYPOTHESIS: Headmix and head registers use cricothyroid (CT) muscle dominant voicing, whereas chest and chestmix registers use thyroarytenoid (TA) muscle dominant voicing. STUDY DESIGN: Cross-sectional study. METHODS: CT and TA electromyographic data obtained from five untrained singers and two trained singers were analyzed to determine CT and TA muscle dominance as a function of register. Simultaneous recordings of TA and CT muscle activity and audio were obtained during production of pitch glides and a variety of midrange and upper pitches in chest, chestmix, headmix, and head registers. RESULTS: TA dominant phonation was only observed for chest productions and headmix/head register productions below 300 Hz. All phonation above 300 Hz, regardless of register, showed CT:TA muscle activity ratios that were CT dominant or close to 1, indicating nearly equal CT and TA muscle activity. This was true for all subjects on all vocal tasks. For the subjects sampled in this study, pitch level appeared to have a greater effect on TA and CT muscle dominance than vocal register. CONCLUSION: Preliminary findings regarding CT and TA dominance and register control do not support the assumption that all chest and chestmix production has greater TA muscle activity than CT muscle activity or that all headmix and head production require greater CT muscle activity than TA muscle activity. The data indicate that pitch level may play a greater role in determining TA and CT dominance than register.

Phonatory characteristics of the excised human larynx in comparison to other species.

OBJECTIVE: The purpose of this study was to determine the conditions needed to elicit phonation from excised human larynges and the resultant range of phonations produced; compare that with similar information previously obtained from canine, pig, sheep, and cow; and relate those findings to previously reported information about viscoelastic properties of the vocal fold tissue (ie, stress-strain curves and Young's modulus). METHODS: Six human larynges of the geriatric group (age range, 70-89) were mounted on the bench without supraglottic structures, and phonation was achieved with the flow of heated and humidified air through the tracheal tube. Using various sutures to mimic the function of the laryngeal muscles, the larynges were put through a series of sustained oscillations with adduction as a control parameter. RESULTS: The human larynges oscillated with an average frequency that was close to the canine larynges, but the oscillation behavior and wide frequency range were similar to those of pig larynges. The similarity of the wide vibration frequency ranges of human and pig larynges may be because of the nonlinear behavior of their elasticity, which is related to the high collagen content of the vocal folds. On the contrary, other species with limited frequency ranges showed almost linear stress-strain curves because of the higher elastin and lower collagen contents. CONCLUSIONS: The physiological differences in the linearity and ranges of oscillation of excised larynges reported in this study and previous studies are reflective of the tissue composition and mechanics.

On the acoustic effects of the supraglottic structures in excised larynges.

The acoustic effects of the supraglottic laryngeal structures (SGSs), including the false vocal folds (FVFs) laryngeal ventricle, and the epiglottis were investigated in an excised canine larynx model with and without these anatomical structures. The purpose of this study was to better understand the acoustic contributions of these structures to phonation. Canine larynges were prepared and mounted over a 3/4 in. tube, which supplied pressurized, heated, and humidified air. Glottal adduction was accomplished by rotating the arytenoids with a suture passed behind the vocal folds to simulate the lateral cricoarytenoid muscle action. The SGSs were kept intact in the first part of the experiment and were removed in the second part. Results indicated that when the FVFs vibrated, a low frequency component was observed in the spectral data. The excised larynx with a SGS had a limited range of frequency with subglottal pressure, while the larynx without a SGS had a larger frequency range. The excised canine larynx with a SGS oscillated with a higher phonation threshold pressure and significantly louder.

Perception of vocal tremor during sustained phonation compared with sentence context.

OBJECTIVES/HYPOTHESIS: Vocal tremor is an acoustical phenomenon characterized by relatively periodic modulations in fundamental frequency and intensity. Although vocal tremor is considered easier to perceive during sustained phonation than during connected speech, systematic comparison between these speech contexts has not been investigated. This investigation compared vocal tremor perception during sustained phonation and connected speech contexts. STUDY DESIGN: This is a prospective, controlled study with randomized conditions. METHODS: Audio recordings from five speakers diagnosed with essential vocal tremor were used for this study. Twenty-four naive adult listeners rated the overall severity (ie, aberrance) of the voice and the degree of shakiness (ie, tremor) during sustained phonation of /i/. A different group of 21 naive adult listeners rated sentence stimuli consisting of two different sentences, one loaded with voiced and the other with voiceless speech sounds. RESULTS: All speakers were rated by listeners to have similar levels of shakiness and overall severity during sustained phonation. However, significantly higher levels of shakiness and overall severity were perceived during sustained phonation than during sentence context. A nonsignificant trend was shown for higher average ratings for shakiness and overall severity on voice-loaded compared with voiceless-loaded sentences. CONCLUSIONS: This study demonstrated that vocal tremor is perceived as significantly more severe during sustained phonation than during connected speech. More importantly, individual speakers differed in their ability to reduce vocal tremor perception during connected speech. Thus, sustained phonation does not necessarily offer a valid estimation of the impact of a vocal tremor on an individual's connected speech.

Laryngeal muscle activity and vocal fold adduction during chest, chestmix, headmix, and head registers in females.

HYPOTHESIS: Commercial singers produce chestmix register by maintaining or increasing adduction of the vocal processes (VPs) and by engaging the thyroarytenoid (TA) muscle to a greater degree than they would to produce head register. STUDY DESIGN: Prospective cohort study. METHODS: Simultaneous recordings of TA and cricothyroid (CT) muscle activity, videonasendoscopy, and audio were obtained from seven female singers during production of a variety of midrange pitches in chest, chestmix, headmix, and head registers. Fast Fourier transforms were performed to measure the energy in the fundamental frequency and in mid and upper frequency harmonics to determine if the productions that were judged as perceptually distinct registers also showed distinctive acoustic characteristics. Then, measures of TA and CT muscle activity and vocal fold adduction ratings were obtained to determine how these varied as a function of pitch and register. RESULTS: Spectral tilt increased as subjects shifted from chest to chestmix to headmix and finally into head register. For same pitch phonation, subjects increased TA muscle activity and vocal fold adduction as they shifted register from head to headmix to chestmix to chest, particularly during production of higher frequencies. CT activity appeared to be more related to pitch rather than register control. CONCLUSION: Nonclassically trained singers were able to produce pitches at the high end of the midrange in chestmix register by increasing TA muscle activity and adduction of the VPs.

Measures of spectral slope using an excised larynx model.

Spectral measures of the glottal source were investigated using an excised canine larynx (CL) model for various aerodynamic and phonatory conditions. These measures included spectral harmonic difference H1-H2 and spectral slope that are highly correlated with voice quality but not reported in a systematic manner using an excised larynx model. It was hypothesized that the acoustic spectra of the glottal source were significantly influenced by the subglottal pressure, glottal adduction, and vocal fold elongation, as well as the resulting vibration pattern. CLs were prepared, mounted on the bench with and without false vocal folds, and made to oscillate with a flow of heated and humidified air. Major control parameters were subglottal pressure, adduction, and elongation. Electroglottograph, subglottal pressure, flow rate, and audio signals were analyzed using custom software. Results suggest that an increase in subglottal pressure and glottal adduction may change the energy balance between harmonics by increasing the spectral energy of the first few harmonics in an unpredictable manner. It is suggested that changes in the dynamics of vocal fold motion may be responsible for different spectral patterns. The finding that the spectral harmonics do not conform to previous findings was demonstrated through various cases. Results of this study may shed light on phonatory spectral control when the larynx is part of a complete vocal tract system.

VFS interjudge reliability using a free and directed search.

Reports in the literature suggest that clinicians demonstrate poor reliability in rating videofluoroscopic swallow (VFS) variables. Contemporary perception theories suggest that the methods used in VFS reliability studies constrain subjects to make judgments in an abnormal way. The purpose of this study was to determine whether a directed search or a free search approach to rating swallow studies results in better interjudge reliability. Ten speech pathologists served as judges. Five clinical judges were assigned to the directed search group (use checklist) and five to the free search group (unguided observations). Clinical judges interpreted 20 VFS examinations of swallowing. Interjudge reliability of ratings of dysphagia severity, affected stage of swallow, dysphagia symptoms, and attributes identified by clinical judges using a directed search was compared with that using a free search approach. Interjudge reliability for rating the presence of aspiration and penetration was significantly better using a free search ("substantial" to "almost perfect" agreement) compared to a directed search ("moderate" agreement). Reliability of dysphagia severity ratings ranged from "moderate" to "almost perfect" agreement for both methods of search. Reliability for reporting all other symptoms and attributes of dysphagia was variable and was not significantly different between the groups.

Phonatory effects of supraglottic structures in excised canine larynges.

The aim of this study is to determine how phonation is affected by the presence and by alteration in the position of the supraglottic structures. The study used three excised canine larynges. A series of pressure-flow experiments were completed first on the excised larynx with false folds and epiglottis intact, then with the epiglottis removed, and finally with the false folds removed. Aerodynamic and acoustic effects were quantified with the analysis of the pressure, flow, and audio signals. The results of the study indicated that (1) elevation of the epiglottis to upright position from a horizontal position decreased subglottal pressure, increased flow (decreased laryngeal resistance), and slightly decreased fundamental frequency; (2) vibration of the false vocal folds induced some irregularity into the acoustic output of the larynx; (3) the presence of the epiglottis and the false vocal folds enhanced the second partial of the acoustic signal; and (4) the absence of the epiglottis and false folds increased low-frequency noise (between 0 and 300 Hz). Alteration in the position of the supraglottic structures affects laryngeal aerodynamics and acoustics, possibly due to biomechanical linkage with true vocal folds. When the supraglottic structures are present they act as resonators, enhancing the second partial and when they are absent (as in persons with supraglottic laryngectomy), low-frequency noise is increased perhaps due to the loss of boundary conditions or due to the presence of loose tissue.

Aerodynamic and acoustic effects of abrupt frequency changes in excised larynges.

PURPOSE: To determine the aerodynamic and acoustic effects due to a sudden change from chest to falsetto register or vice versa. It was hypothesized that the continuous change in subglottal pressure and flow rate alone (pressure-flow sweep [PFS]) can trigger a mode change in the canine larynx. METHOD: Ten canine larynges were each mounted over a tapered tube that supplied pressurized, heated, and humidified air. Glottographic signals were recorded during each PFS experiment, during which airflow was increased in a gradual manner for a period of 20-30 s. RESULTS: Abrupt changes in fundamental frequency (F(0)) and mode of vibration occurred during the PFS in the passive larynx without any change in adduction or elongation. The lower frequency mode of oscillation of the vocal folds, perceptually identified as the chest register, had relatively large amplitude oscillation, significant vocal fold contact, a rich spectral content, and a relatively loud audio signal. The higher frequency mode of oscillation, perceptually identified as falsetto, had little or no vocal fold contact and a dominant first partial. Relatively abrupt F(0) changes also occurred for gradual adduction changes, with the chest register corresponding to greater adduction, falsetto to less adduction.

Sickle red cell-endothelium interactions.

Periodic recurrence of painful vaso-occlusive crisis is the defining feature of sickle cell disease. Among multiple pathologies associated with this disease, sickle red cell-endothelium interaction has been implicated as a potential initiating mechanism in vaso-occlusive events. This review focuses on various interrelated mechanisms involved in human sickle red cell adhesion. We discuss in vitro and microcirculatory findings on sickle red cell adhesion, its potential role in vaso-occlusion, and the current understanding of receptor-ligand interactions involved in this pathological phenomenon. In addition, we discuss the contribution of other cellular interactions (leukocytes recruitment and leukocyte-red cell interaction) to vaso-occlusion, as observed in transgenic sickle mouse models. Emphasis is given to recently discovered adhesion molecules that play a predominant role in mediating human sickle red cell adhesion. Finally, we analyze various therapeutic approaches for inhibiting sickle red cell adhesion by targeting adhesion molecules and also consider therapeutic strategies that target stimuli involved in endothelial activation and initiation of adhesion.

Effects of a semioccluded vocal tract on laryngeal muscle activity and glottal adduction in a single female subject.

Voice training exploits semiocclusives, which increase vocal tract interaction with the source. Modeling results suggest that vocal economy (maximum flow declination rate divided by maximum area declination rate, MADR) is improved by matching the glottal and vocal tract impedances. Changes in MADR may be correlated with thyroarytenoid (TA) muscle activity. Here the effects of impedance matching are studied for laryngeal muscle activity and glottal resistance. One female repeated [pa:p:a] before and immediately after (a) phonation into different-sized tubes and (b) voiced bilabial fricative [beta:]. To allow estimation of subglottic pressure from the oral pressure, [p] was inserted also in the repetitions of the semiocclusions. Airflow was registered using a flow mask. EMG was registered from TA, cricothyroid (CT) and lateral cricoarytenoid (LCA) muscles. Phonation was simulated using a 7 x 5 x 5 point-mass model of the vocal folds, allowing inputs of simulated laryngeal muscle activation. The variables were TA, CT and LCA activities. Increased vocal tract impedance caused the subject to raise TA activity compared to CT and LCA activities. Computer simulation showed that higher glottal economy and efficiency (oral radiated power divided by aerodynamic power) were obtained with a higher TA/CT ratio when LCA activity was tuned for ideal adduction.

Quantitative contributions of the muscles of the tongue, floor-of-mouth, jaw, and velum to tongue-to-palate pressure generation.

PURPOSE: The purpose of this investigation was to evaluate the relationship between tongue-to-palate pressure and the electromyography (EMG) measured from the mylohyoid, anterior belly of the digastric, geniohyoid, medial pterygoid, velum, genioglossus, and intrinsic tongue muscles. Methods Seven healthy adults performed tongue-to-palate pressure tasks at known percentages of their maximum pressure while intramuscular EMG was recorded from the muscles stated above. Multiple regression analysis was performed. RESULTS: Predictors of pressure included the posterior fibers of the genioglossus, mylohyoid, anterior belly of digastric, medial pterygoid, and intrinsic tongue. CONCLUSIONS: Increasing tongue-to-palate pressure coincides with increased muscle activity. Activation of the floor-of-mouth, tongue, and jaw closing muscles increased tongue-to-palate pressure. These findings support the use of a tongue-press exercise to strengthen floor-of-mouth muscles, tongue, and jaw-closing muscles.

Laryngeal muscle activity in giggle: a damped oscillation model.

The acoustic properties of giggle, a mild form of laughter, were studied. The purpose was to determine if there is some uniqueness to the frequency and number of vocalization bursts in giggle. The underlying hypothesis was that a neuromechanical oscillator serves as an activator for rhythmic vocalizations, as in vibrato, with a pair of agonist-antagonist adductor muscles alternating in a 180 degrees phase relationship. Electromyographic activity of the posterior cricoarytenoid muscle was always measured, in conjunction with either lateral cricoarytenoid or thyroarytenoid muscle activity. Results indicate that muscle activations do alternate and that these activations do not diminish during successive bursts, even though the amplitude and duty ratio of the bursts decreases. It is reasoned that reduced lung pressure and lung volume limit the number of bursts and their duty ratio, while speed of intrinsic laryngeal muscle contraction dictates the burst frequency.

Small-molecule cyclic alpha V beta 3 antagonists inhibit sickle red cell adhesion to vascular endothelium and vasoocclusion.

Abnormal adhesion of sickle red blood cells (SS RBCs) to vascular endothelium may play an important role in vasoocclusion in sickle cell disease. Accruing evidence shows that endothelial alpha V beta 3-integrin has an important role in SS RBC adhesion because of its ability to bind several adhesive proteins implicated in this interaction. In the present studies, we tested therapeutic efficacy of small-molecule cyclic pentapeptides for their ability to block alpha V beta 3-mediated SS RBC adhesion by using two well-established assay systems, i.e., cultured human umbilical vein endothelial cells (HUVEC) and artificially perfused mesocecum vasculature of the rat under flow conditions. We tested the efficacy of two RGD-containing cyclic pentapeptides, i.e., cRGDFV (EMD 66203) and cRGDF-ACHA (alpha-amino cyclohexyl carboxylic acid) (EMD 270179), based on their known ability to bind alpha V beta 3. An inactive peptide, EMD 135981 (cR beta-ADFV) was used as control. Cyclization and the introduction of D-Phe (F) results in a marked increase in the ability of cyclic peptides to selectively bind alpha V beta 3 receptors. In the mesocecum vasculature, both EMD 66203 and EMD 270179 ameliorated platelet-activating factor-induced enhanced SS RBC adhesion, postcapillary blockage, and significantly improved hemodynamic behavior. Infusion of a fluorescent derivative of EMD 66203 resulted in colocalization of the antagonist with vascular endothelium. Also, pretreatment of HUVEC with either alpha V beta 3 antagonist resulted in a significant decrease in SS RBC adhesion. Because of their metabolic stability, the use of these cyclic alpha V beta 3 antagonists may constitute a novel therapeutic strategy to block SS RBC adhesion and associated vasoocclusion under flow conditions.

Aerodynamic and acoustic effects of false vocal folds and epiglottis in excised larynx models.

OBJECTIVES: The purpose of this study was to examine the aerodynamic and acoustic effects of the false vocal folds and the epiglottis on excised larynx phonation. METHODS: Several canine larynges were prepared and mounted over a tapered tube that supplied pressurized, heated, and humidified air. Glottal adduction was accomplished either by using two-pronged probes to press the arytenoids together or by passing a suture to simulate lateral cricoarytenoid muscle activation. First, the excised larynx with false vocal folds and epiglottis intact was subjected to a series of pressure-flow experiments with longitudinal tension and adduction as major control parameters. Then, the epiglottis and finally the false vocal folds were removed and the experiment was repeated. The subglottal pressure and the electroglottographic, flow rate, audio, and sound pressure signals were recorded during each experiment. Glottal flow resistance was calculated from the pressure and flow signals. The electroglottographic signal was used to extract the fundamental frequency. RESULTS: It was found that the false vocal folds and the epiglottis offer a positive contribution to the glottal resistance and sound intensity of the larynx. Also, vocal fold elongation and glottal medial compression caused an increase in glottal resistance. The pressure-flow relationships were approximately linear regardless of the structure. CONCLUSIONS: The addition of the supraglottic laryngeal structures has a significant impact on both aerodynamic and acoustic characteristics of excised larynges.

Adherent leukocytes capture sickle erythrocytes in an in vitro flow model of vaso-occlusion.

Recent in vivo studies suggest that adherent leukocytes bind RBCs and contribute to the microvascular pathology that characterizes sickle cell disease (SCD). A parallel-plate flow assay was used: to investigate the capture of RBCs by adherent neutrophils, monocytes, and T-lymphocytes; to examine whether RBC capture is elevated in patients with SCD; and to determine whether hydroxyurea (HU) therapy affects these interactions. Four measures of cell-cell adhesion were used: adhesion of leukocytes to TNF-alpha-treated human umbilical vein endothelial cells (HUVECs), percent of adherent leukocytes that captured RBCs, number of RBCs captured per interacting leukocyte, and duration of RBC capture. Leukocyte subpopulations from sickle patients were more adherent to activated ECs and captured more RBCs per interacting leukocyte than the corresponding subpopulations from healthy controls. While HU did not affect leukocyte adhesion to activated ECs, it reduced the proportion of adherent leukocytes that captured RBCs, as well as the number of RBCs captured per neutrophil. T-lymphocytes demonstrated elevated adhesion in all measures, and may be the leukocyte subpopulation whose behavior is most altered in SCD. Our findings suggest that neutrophils, monocytes, and T-lymphocytes could all be involved in adhesive interactions with autologous RBCs in patients with SCD.