Feedback Conditions Research Articles

The effects of visual information deprivation and feedback balance training on balance in patients with stroke.

Patients with stroke depend on visual information due to balance deficits. Therefore, it is believed that appropriate visual deprivation training could have an impact on improving balance abilities. The purpose of this study was to compare the effects of balance training performed in visual deprivation and feedback conditions on balance in stroke survivors. The 39 participants were randomly assigned to either the Visual Deprivation Group (VDG; n = 13), the Visual Feedback Group (VFG; n = 13), or the Control Group (CG; n = 13). The training sessions were conducted five times a week for three weeks. Participants completed the Berg Balance Scale (BBS), Timed Up and Go test (TUG), Four Square Step Test (FSST), and Limit of Stability (LOS) assessments. The VDG showed significant improvements in BBS, FSST, TUG, and LOS. In VFG, significant improvements were observed in BBS and TUG. There were statistically significant differences among the groups in all variables related to balance. The results of this study suggest that balance training under visual deprivation is effective in improving static and dynamic balance and gait in patients with stroke. In other words, patients with stroke need to reduce their over-reliance on visual information.

An ethical leadership assessment center pilot: Assessing and developing moral person and moral manager dimensions

Abstract Ethical leaders are those who exemplify moral behavior personally, as well as those who facilitate follower ethical behavior. Although recent attention has been given to the ethical leadership construct, there remains a lack of innovation regarding the assessment and development of ethical leaders in organizations. To address these issues, a pilot study was conducted to examine the convergent validity of an ethical leadership assessment center, as well as the efficacy of using assessment center feedback to foster ethical leadership. Assessees completed a battery of pre tests, a virtual business simulation with a novel exercise, and a set of post tests. Half of the assessees were randomly assigned to a feedback condition, whereas the other half did not receive feedback until after the post tests were completed. Due to low statistical power, quantitative results were inconclusive. Nevertheless, qualitative insights were gained that point to implications for validating assessment center methodologies when assessing and developing ethical leadership.

Multi-bounce self-mixing in terahertz metasurface external-cavity lasers

The effects of optical feedback on a terahertz (THz) quantum-cascade metasurface vertical-external-cavity surface-emitting laser (QC-VECSEL) are investigated via self-mixing. A single-mode 2.80 THz QC-VECSEL operating in continuous-wave is subjected to various optical feedback conditions (i.e., feedback strength, round-trip time, and angular misalignment) while variations in its terminal voltage associated with self-mixing are monitored. Due to its large radiating aperture and near-Gaussian beam shape, we find that the QC-VECSEL is strongly susceptible to optical feedback, which is robust against misalignment of external optics. This, in addition to the use of a high-reflectance flat output coupler, results in high feedback levels associated with multiple round-trips within the external cavity-a phenomenon not typically observed for ridge-waveguide QC-lasers. Thus, a new theoretical model is established to describe self-mixing in the QC-VECSEL. The stability of the device under variable optical feedback conditions is also studied. Any mechanical instabilities of the external cavity (such as vibrations of the output coupler), are enhanced due to feedback and result in low-frequency oscillations of the terminal voltage. The work reveals how the self-mixing response differs for the QC-VECSEL architecture, informs other systems in which optical feedback is unavoidable, and paves the way for QC-VECSEL self-mixing applications.

Global adaptive practical tracking control for high‐order uncertain nonstrict feedback nonlinear systems with unknown control coefficients

SummaryIn this article, the problem of global adaptive practical tracking for high‐order uncertain nonstrict feedback nonlinear systems with unknown control coefficients is studied. To avoid the algebraic loop problem associated with the nonstrict feedback condition and guarantee the controllability of the tracking error, a novel dual dynamic gain scaling method is introduced to compensate nonlinearities and the tracking error simultaneously. Besides, by incorporating the sign functions into the design of adding a power integrator, a general approach for the handing of unknown control coefficients and the direction design of the controller is developed. The presented control scheme can ensure that all system states are globally bounded without constraints on state variables while the reference signal is tracked with expected precision. Three simulation examples, including a practical application, are provided to illustrate the validity of the control scheme.

Random Numbers Generated Based on Dual-Channel Chaotic Light

This paper presents a chaotic system based on novel semiconductor nanolasers (NLs), systematically analyzing its chaotic region and investigating the influence of key parameters on the unpredictability of chaotic output. This study found that under optical feedback conditions, NLs generate chaos across a wide range of feedback parameters, with the highly unpredictable region completely overlapping with the chaotic region. Further injection into the slave lasers enhances the chaotic output, expanding the range of unpredictability. Additionally, we analyzed the impact of internal parameter mismatch on the complexity of chaotic signals and found it to be similar to the scenario when parameters are matched. Using this chaotic system as an entropy source, we constructed a random number generator (RNG) and investigated the effects of internal parameters mismatch and differences in the injection parameters on the generator’s performance. The simulation results show that the RNG performs well under different parameter settings, and the generated random sequences pass all random number tests successfully. Therefore, this chaotic system can yield a high-complexity chaotic light source with appropriate parameter selection, and when combined with effective post-processing, it can generate high-quality random numbers. This is crucial for advancing the realization of small-sized, high-randomness RNGs.

Characterizing the spike timing of a chaotic laser by using ordinal analysis and machine learning.

Semiconductor lasers with optical feedback are well-known nonlinear dynamical systems. Under appropriate feedback conditions, these lasers emit optical pulses that resemble neural spikes. Influenced by feedback delay and various noise sources, including quantum spontaneous emission noise, the dynamics are highly stochastic. A good understanding of the spike timing statistics is needed to develop photonic systems capable of using the fast-spiking laser output for novel applications, such as information processing or random number generation. Here we analyze experimental sequences of inter-spike intervals (ISIs) recorded when a sinusoidal signal was applied to the laser current. Different combinations of the DC value and frequency of the signal applied to the laser lead to ISI sequences with distinct statistical properties. This variability prompts an investigation into the relationship between experimental parameters and ISI sequence statistics, aiming to uncover potential encoding methods for optical spikes, since this can open a new way of encoding and decoding information in sequences of optical spikes. By using ordinal analysis and machine learning, we show that the ISI sequences have statistical ordinal properties that are similar to Flicker noise signals, characterized by a parameter α that varies with the signal that was applied to the laser current when the ISIs were recorded. We also show that for this dataset, the (α, permutation entropy) plane is more informative than the (complexity, permutation entropy) plane because it allows better differentiation of ISI sequences recorded under different experimental conditions, as well as better differentiation of original and surrogate ISI sequences.

Attractive Ellipsoid Technique for a Decentralized Passivity-Based Voltage Tracker for Islanded DC Microgrids

A new passivity-based voltage tracker for islanded Direct Current (DC) microgrids is presented in this paper. The proposed design develops a new sufficient condition for passivity-based state feedback with proportional and integral control using the attracting ellipsoid method. In this paper, we consider the time behavior of the extended vector, which completely describes the principle properties of the closed-loop system such as the boundedness of the trajectories within some ellipsoid and the dependence of its “size” on the feedback gains. The next step, which we are realizing in this paper, is the minimization of the attractive ellipsoid by selecting the “best” admissible feedback parameters. Here, it is important to note that the applied feedback is of PD-type (proportional differential) on the system state and I-type (integral) on the output. This is a new construction of the suggested feedback which gives several advantages for a designer. The suggested control is decentralized and uses only the local states; it is cost-effective and avoids the time delays in the communication networks which are needed if centralized control is used. The suggested control is carried out in the bilinear matrix inequality (BMI) framework. Extensive simulation is performed on a test system composed of renewable energy sources, under plug and play (PnP) operations, and uncertainties in distribution lines and loads. The performance of the proposed decentralized voltage controller is compared with that of a voltage tracker present in the literature. The comparison shows the improvements introduced by the proposed control ensure the stability of the dc bus voltage and a quick response under different scenarios of operating conditions.

Supportive error feedback fosters students' adaptive reactions towards errors: Evidence from a targeted online intervention with Italian middle school students.

Although it is well established that students' adaptive reactions towards errors promote learning outcomes, little is still known about the role of error feedback in promoting these reactions. Through a targeted intervention based on an online teaching unit, this study aimed at testing whether supportive error feedback promotes more adaptive students' reactions towards errors and higher learning outcomes. A total of 250 (Mage   = 12.18, SD = .89; 46.4% girls) Italian middle school students took part in the intervention. Students were randomly assigned to either a discouraging error feedback condition (n  = 124) or a supportive error feedback condition (n  = 126). The intervention consisted of an online teaching unit, which students filled in at home, that was divided into pre-test, intervention and post-test phases. During the intervention, students replied to training questions and every time they made an error, informative feedback appeared: supportive smileys and sentences in the supportive feedback condition, and disappointed smileys and sentences in the discouraging feedback condition. Before the intervention, students filled in the pre-test and after the intervention, students reported their reactions towards errors and filled in the post-test. Receiving supportive feedback resulted in more adaptive affective-motivational reactions towards errors, which in turn were related to more adaptive action reactions towards errors. Differently from our expectations, action reactions towards errors were not related to the post-test scores. Our findings can inform the development of online teaching units that promote an error-oriented approach.

Change my mind

Abstract: High dropout rates at universities, often caused by false expectations and a lack of motivation, pose a serious problem in higher education. Online self-assessments (OSAs) assess expectations regarding a field of study (major) and provide feedback on the reality of the major, thus pointing out expectation-reality discrepancies as well as helping prospective students choose a major. Based on cognitive dissonance theory, pointing out expectation-reality discrepancies should be related to changes in motivation for the major (expectancies for success, subjective values, intention to choose a major) and this relationship should be strengthened by feedback. Past research has shown that OSAs can correct expectations and that expectation-reality discrepancies are related to motivation but has not investigated the role of feedback for this process. Therefore, we extend past research by examining whether the positive relationships between expectation-reality discrepancies and changes in motivation for a major are stronger for prospective students who receive feedback on their expectation-reality discrepancies than for prospective students who do not receive feedback after the assessment. We conducted a field experiment in which 234 prospective students were randomly assigned to one of two groups (EG1 = OSA including feedback; EG2 = OSA without feedback). As hypothesized larger expectation-reality discrepancies were associated with larger changes in motivation for a major (expectancies for success, subjective values, intention to choose a major). Beyond that, we found a moderation effect of the feedback condition showing that the positive relationships between expectation-reality discrepancies and expectancies for success were stronger when prospective students received feedback (vs. no feedback). As feedback only showed effects beyond expectation-reality discrepancies in one of the considered outcomes, both the development of assessment and feedback should be targeted to optimize the effectiveness of OSAs.

The interplay of sensory feedback, arousal, and action tremor amplitude in essential tremor.

Essential tremor (ET) amplitude is modulated by visual feedback during target driven movements and in a grip force task. It has not been examined yet whether visual feedback exclusively modulates target force tremor amplitude or if other afferent inputs like auditory sensation has a modulatory effect on tremor amplitude as well. Also, it is unknown whether the enhanced sensory feedback causes an increase of arousal in persons with ET (p-ET). We hypothesized that (1) amplitude of tremor is modulated by variation of auditory feedback in the absence of visual feedback in a force tremor paradigm; (2) increase of tremor amplitude coincides with pupillary size as a measure of arousal. 14 p-ET and 14 matched healthy controls (HC) conducted a computer-based experiment in which they were asked to match a target force on a force sensor using their thumb and index finger. The force-induced movement was fed back to the participant visually, auditory or by a combination of both. Results showed a comparable deviation from the target force (RMSE) during the experiment during all three sensory feedback modalities. The ANOVA revealed an effect of the high vs. low feedback condition on the tremor severity (Power 4-12Hz) for the visual- and also for the auditory feedback condition in p-ET. Pupillometry showed a significantly increased pupil diameter during the auditory involved high feedback conditions compared to the low feedback conditions in p-ET. Our findings suggest that action tremor in ET is firstly modulated not only by visual feedback but also by auditory feedback in a comparable manner. Therefore, tremor modulation seems to be modality independent. Secondly, high feedback was associated with a significant pupil dilation, possibly mirroring an increased arousal/perceived effort.

On the structure of the infinitesimal generators of scalar one-dimensional semigroups with discrete Lyapunov functionals

AbstractDynamical systems generated by scalar reaction-diffusion equations on an interval enjoy special properties that lead to a very simple structure for the semiflow. Among these properties, the monotone behavior of the number of zeros of the solutions plays an essential role. This discrete Lyapunov functional contains important information on the spectral behavior of the linearization and leads to a Morse-Smale description of the dynamical system. Other systems, like the linear scalar delay differential equations under monotone feedback conditions, possess similar kinds of discrete Lyapunov functions. Here we discuss and characterize classes of linear equations that generate semiflows acting on $$C^0[0,1]$$ C 0 [ 0 , 1 ] or on $$C^1[0,1]$$ C 1 [ 0 , 1 ] which admit discrete Lyapunov functions related to the zero number. We show that, if the space is $$C^1[0,1]$$ C 1 [ 0 , 1 ] , the corresponding equations are essentially parabolic partial differential equations. In contrast, if the space is $$C^0[0,1]$$ C 0 [ 0 , 1 ] , the corresponding equations are generalizations of monotone feedback delay differential equations.

Corticostriatal activity related to performance during continuous de novo motor learning

Corticostriatal regions play a pivotal role in visuomotor learning. However, less research has been done on how fMRI activity in their subregions is related to task performance, which is provided as visual feedback during motor learning. To address this, we conducted an fMRI experiment in which participants acquired a complex de novo motor skill using continuous or binary visual feedback related to performance. We found a highly selective response related to performance in the entire striatum in both conditions and a relatively higher response in the caudate nucleus for the binary feedback condition. However, the ventromedial prefrontal cortex (vmPFC) response was significant only for the continuous feedback condition. Furthermore, we also found functional distinction of the striatal subregions in random versus goal-directed motor control. These findings underscore the substantial effects of the visual feedback indicating performance on distinct corticostriatal responses, thereby elucidating its significance in reinforcement-based motor learning.

Facial feedback manipulation influences the automatic detection of unexpected emotional body expressions

Unexpected or changing facial expressions are known to be able to engage more automatic processing than frequently occurring facial expressions, thereby inducing a neural differential wave response known as expression mismatch negativity (EMMN). Recent studies have shown that EMMN can be modulated by the observer's facial feedback (i.e., feedback from their own facial movements). A similar EMMN activity has been discovered for body expressions, but thus far only a few emotion types have been investigated. It is unknown whether the EMMNs evoked by body expressions can be influenced by facial feedback. To explore this question, we recorded EEG activity of 29 participants in the reverse oddball paradigm. Here two unexamined categories of body expressions were presented, happy and sad, placed in two paired stimulus sequences: in one the happy body was presented with a probability of 80% (standards) while the sad body was presented with a probability of 20% (deviants), and in the other the probabilities were reversed. The facial feedback was manipulated by different pen holding conditions (i.e., participants holding the pen with the teeth, lips, or nondominant hand). The nonparametric cluster permutation test revealed significant happy and sad body-related EMMN (bEMMN) activities. The happy-bEMMN were more negative than sad-bEMMN within the range of 100–150 ms. Additionally, the bEMMN amplitude of both emotions is modulated by the facial feedback conditions. These results expand the range of emotional types applicable to bEMMN and provide evidence for the validity of the facial feedback hypothesis across emotional carriers.

Three Sliding Probes Placed on Forelimb Skin for Proprioceptive Feedback Differentially yet Complementarily Contribute to Hand Gesture Detection and Object-Size Discrimination

The purpose was to assess the effectiveness of three sliding tactile probes placed on the forelimb skin to provide proprioceptive feedback for the detection of hand gestures and discrimination of object size. Tactile contactors representing the first three fingers were driven along the proximodistal axis by linear servo motors. Twenty healthy subjects were involved in the gesture detection test, with 10 of them also participating in the object-size discrimination task. Motors were controlled by computer in the first four sessions of the gesture detection experiment, while the fifth session utilized a sensorized glove. Both the volar and dorsal sides of the forearm were examined. In the object-size discrimination experiment, the method was exclusively assessed on the volar surface under four distinct feedback conditions, including all fingers and each finger separately. The psychophysical data were further analyzed using a structural equation model (SEM) to evaluate the specific contributions of each individual contactor. Subjects consistently outperformed the chance level in detecting gestures. Performance improved up to the third session, with better results obtained on the volar side. The performances were similar in the fourth and fifth sessions. The just noticeable difference for achieving a 75% discrimination accuracy was found to be 2.90 mm of movement on the skin. SEM analysis indicated that the contactor for the index finger had the lowest importance in gesture detection, while it played a more significant role in object-size discrimination. However, all fingers were found to be significant predictors of subjects' responses in both experiments, except for the thumb, which was deemed insignificant in object-size discrimination. The study highlights the importance of considering the partial contribution of each degree of freedom in a sensory feedback system, especially concerning the task, when designing such systems.

Investigating pedagogical agents' scaffolding of self‐regulated learning in relation to learners' subgoals

AbstractIntelligent tutoring systems (ITSs) incorporate pedagogical agents (PAs) to scaffold learners' self‐regulated learning (SRL) via prompts and feedback to promote learners' monitoring and regulation of their cognitive, affective, metacognitive and motivational processes to achieve their (sub)goals. This study examines PAs' effectiveness in scaffolding and teaching SRL during learning with MetaTutor, an ITS on the human circulatory system. Undergraduates (N = 118) were randomly assigned to a condition: Control Condition (i.e. learners could only self‐initiate SRL strategies) and Prompt and Feedback Condition (i.e. PAs prompted learners to engage in SRL). Learners' log‐file data captured when strategies were used, the initiator of the strategy (i.e. learner and PA), and the relevance of instructional content pages in relation to learner subgoals. While results showed that PAs were effective scaffolders of SRL in which they prompted learners to engage in SRL strategies more when content was relevant towards their subgoals and as time on page and task increased, there were mixed findings about the effectiveness of PAs as teachers of SRL. Findings show how production rules guiding PA prompts can improve their scaffolding and teaching of SRL across the learning task – through contextualizing SRL strategies to the instructional content and in relation to the relevance of the content to learners' subgoals.Practitioner notesWhat is already known about this topic Most learners struggle to efficiently and effectively use self‐regulated learning (SRL) strategies to attain goals and subgoals. There is a need for SRL to be scaffolded for learners to manage multiple goals and subgoals while learning about complex STEM topics. Intelligent tutoring systems (ITSs) typically incorporate pedagogical agents (PAs) to prompt learners to engage in SRL strategy and provide feedback. There are mixed findings on the effectiveness of PAs in scaffolding learners' SRL. What this paper adds We consider PAs not only scaffolders but also teachers of SRL. Results showed that while PAs encouraged the use of SRL strategies when the content was relevant to subgoals, they did not discourage the use of SRL strategies when the content was not relevant. Results for this study were mixed in their support of PAs as teachers of SRL. Learners increasingly depended on PAs to prompt SRL strategies as time on task progressed. Implications for practice and/or policy PAs are effective scaffolders of SRL with more research needed to understand their role as teachers of SRL. PA scaffolding is more essential as time on task progresses. When deploying specific cognitive and metacognitive SRL strategies, the relevance of the content to learners' subgoals should be taken into account.

Learning from errors versus explicit instruction in preparation for a test that counts.

Although the generation of errors has been thought, traditionally, to impair learning, recent studies indicate that, under particular feedback conditions, the commission of errors may have a beneficial effect. This study investigates the teaching strategies that facilitate learning from errors. This 2-year study, involving two cohorts of ~88 students each, contrasted a learning-from-errors (LFE) with an explicit instruction (EI) teaching strategy in a multi-session implementation directed at improving student performance on the high-stakes New York State Algebra 1 Regents examination. In the LFE condition, instead of receiving instruction on 4 sessions, students took mini-tests. Their errors were isolated to become the focus of 4 teacher-guided feedback sessions. In the EI condition, teachers explicitly taught the mathematical material for all 8 sessions. Teacher time-on in the LFE condition produced a higher rate of learning than did teacher time-on in the EI condition. The learning benefit in the LFE condition was, however, inconsistent across teachers. Second-by-second analyses of classroom activities, directed at isolating learning-relevant differences in teaching style revealed that a highly interactive mode of engaging the students in understanding their errors was more conducive to learning than was teaching directed at getting to the correct solution, either by lecturing about corrections or by interaction focused on corrections. These results indicate that engaging the students interactively to focus on errors, and the reasons for them, facilitates productive failure and learning from errors.

Accretion and obscuration in merger-dominated luminous red quasars

ABSTRACT We present an analysis of the X-ray properties of 10 luminous, dust-reddened quasars from the FIRST-2MASS (F2M) survey based on new and archival Chandra observations. These systems are interpreted to be young, transitional objects predicted by merger-driven models of quasar/galaxy co-evolution. The sources have been well studied from the optical through mid-infrared, have Eddington ratios above 0.1, and possess high-resolution imaging, most of which shows disturbed morphologies indicative of a recent or ongoing merger. When combined with previous X-ray studies of five other F2M red quasars, we find that the sources, especially those hosted by mergers, have moderate-to-high column densities (NH ≃ 1022.5–23.5 cm−2) and Eddington ratios high enough to enable radiation pressure to blow out the obscuring material. We confirm previous findings that red quasars have dust-to-gas ratios that are significantly lower than the value for the Milky Way’s interstellar medium, especially when hosted by a merger. The dust-to-gas ratio for two red quasars that lack evidence for merging morphology is consistent with the Milky Way and they do not meet the radiative feedback conditions for blow-out. These findings support the picture of quasar/galaxy co-evolution in which a merger results in feeding of and feedback from an AGN. We compare the F2M red quasars to other obscured and reddened quasar populations in the literature, finding that, although morphological information is lacking, nearly all such samples meet blow-out conditions and exhibit outflow signatures suggestive of winds and feedback.

Gender, Race/Ethnicity, and Patient-Therapist Matching on Gender and Race/Ethnicity: Predictors/Moderators of the Effectiveness of Trust/Respect Feedback.

A plethora of studies has exhibited the effectiveness of using measurement-based care feedback systems within mental health services to improve treatment outcomes; however, patient gender/race and patient-therapist matching on gender and race remain relatively unexplored as predictors/moderators in feedback studies. We conducted predictor/moderator analyses focusing on the relation of gender, race/ethnicity, and patient-therapist gender and race/ethnicity matching on two outcomes: patient self-reported levels of (1) functioning and (2) trust/respect within the therapeutic relationship. We used data from a randomized controlled trial studying the effectiveness of a feedback system comparing patient-reported levels of trust and respect towards their provider (together with symptom feedback) in comparison to symptom only feedback. We found that men improved in functioning more than women when their therapists received trust/respect feedback compared to symptom only feedback (F[1, 902] = 9.79, p = .002, d = 0.21). We also found that dyads matched on race/ethnicity but not gender, and those matched on gender but not race/ethnicity, improved in functioning over time more than dyads mismatched on both gender and race/ethnicity and those matched on both gender and race/ethnicity (F[1, 897] = 8.63, p = .0034, d = 0.20). On trust/respect outcomes, we found a gender difference over time (F[1, 759] = 6.61, p = .01, d = 0.19), a gender matching difference by feedback condition interaction (F[1, 757] = 5.25, p = .02, d = 0.17), and a racial/ethnic matching difference on trust/respect scores over time (F[1, 785] = 3.89, p = .049, d = 0.14). Male patients showed an initial decrease followed by a steady increase in trust/respect over time while female patients showed an initial increase followed by a steady decrease. Gender-matched therapeutic dyads showed higher levels of trust/respect compared to mismatched dyads when therapists received symptom only feedback, but this difference was not apparent when trust/respect feedback was provided. Dyads mismatched on race/ethnicity improved steadily in trust/respect over time, but matched dyads decreased in trust/respect after an initial increase. Future research should focus on the use of feedback systems to enhance outcomes for patients with specific gender and racial/ethnic identities.

Haptic Feedback, Performance and Arousal: A Comparison Study in an Immersive VR Motor Skill Training Task.

This paper investigates the relationship between fine motor skill training in VR, haptic feedback, and physiological arousal. To do so, we present the design and development of a motor skill task (buzzwire), along with a custom vibrotactile feedback attachment for the Geomagic Touch haptic device. A controlled experiment following a between-subjects design was conducted with 73 participants, studying the role of three feedback conditions - visual/kinesthetic, visual/vibrotactile and visual only - on the learning and performance of the considered task and the arousal levels of the participants. Results indicate that performance improved in all three feedback conditions after the considered training session. However, participants reported no change in self-efficacy and in terms of presence and task load (NASA-TLX). All three feedback conditions also showed similar arousal levels. Further analysis revealed that positive changes in performance were linked to higher arousal levels. These results suggest the potential of haptic feedback to affect arousal levels and encourage further research into using this relationship to improve motor skill training in VR.

Skin-stretch Haptic Feedback Augmentation Improves Performance in a Simulated Laparoscopic Palpation Task.

Laparoscopic surgery brings substantial benefits to patients. However, it remains challenging for surgeons because of motion constraints and perception limitations. Notably, the perception of interactions with organs is largely compromised. This paper evaluates the effectiveness of a forearm-based skin-stretch haptic feedback system rendering surgical tool tip force. Twenty novice participants had to discern the stiffness of samples to investigate stiffness perception in a simulated laparoscopic task. The experimental protocol involved manipulating samples with three difficulty levels and testing three feedback conditions: no augmentation, visual feedback, and tactile feedback. The results demonstrate that feedback significantly enhances the success rate of laparoscopic palpation tasks. The proposed tactile feedback boosts confidence and task speed and reduces peak force and perceived workload. These benefits become even more pronounced when difficulty increases. These promising findings affirm the value of skin-stretch haptic feedback augmentation in improving performance for simulated laparoscopy tasks, paving the way for more integrated and deployable devices for the operating room.