# Designing Pedagogically Effective Haptic Systems for Learning: A Review
## 3 Haptics Applications for Learning
### Medicine
#### 3.2.1 Palpatory Diagnosis and Treatment  
The use of haptic or tactile learning plays an important role in medical professions. There are concepts and procedures that require tactile feedback to determine success, such as: palpatory diagnosis, injections, or surgical procedures. The implementation of haptic interfacing for these professions have shown great promise, with positive subjective reports [30]. Palpation is the process where physicians analyze tissues or organs via their fingers to detect anomalies [31]. This assessment technique employed by medical professionals is important for determining patient characteristics and plays a large role in human and veterinary medicine [30]. Palpation can be utilized to effectively locate medically relevant anomalies (e.g., tumors) and targets (e.g., veins) underneath the skin [31; 32]. While the procedure of palpation is economical and quick, it relies on the presence of real-life patients with specific medical problems to ensure adequate training. The limited supply of real-life examples can significantly hamper teaching palpation [30]. Haptic technology can enable the learner to experience a variety of different patient problems with lower restrictions on time, allowing the user to spend more time becoming familiar with a wide variety of different diagnoses, thus likely improving the user's palpation skills. A study conducted by [PERSON] and [PERSON] [30] examined the implementation of a palpatory diagnostic haptic module on a group of medical students. Palpatory procedures included used touch to determine common afflictions, including: bump height, bump location, facial drag, pitting edema, ropey, and stiffness. The participants in the study were twenty-two osteopathic medical students from the Ohio University College of Medicine. After completing the haptic modules, the subjects completed a subjective evaluation questionnaire about their experience. Results showed that the majority of the students believed that the practice with the haptic modules helped to improve their palpatory skills, suggesting that the haptic module would make a great addition to their pre-clinical training. [PERSON] et al. [33] explored a pseudo-haptic device and its ability to teach palpation for tumor identification under different conditions. Pseudo-haptics is a feedback method which visually mimics force feedback through appropriately adapted visual cues. Pseudo-haptic feedback (PHF) generates virtual \"forces\" through visual feedback only (i.e., cursor displacements), so no force feedback devices are necessary. However, PHF can be easily combined with haptic feedback. In [PERSON] et al. 's study, four different palpation scenarios were deployed to investigate the effects of different types of feedback on the users' nodule detection time during palpation and determine which combination may best strengthen haptic perception. Four different tests were conducted by the twenty participants: (1) Manual palpation, (2) PHF, (3) FF, and (4) PHF and FF. The manual palpation was conducted on silicone blocks with hard inclusions inside which represented tumors. Participants reported the locations where they believed to have sensed the hard nodules and were timed until they thought they had identified all of the nodules. For the PHF group, participants were asked to palpate the virtual soft tissue block with the embedded hard nodules inside using only PHF and to indicate the positions of the hard nodules they believed to have found, while being timed until they believed they had found all the nodules. The force feedback group completed the same procedure as mentioned above relying on force feedback only. The final test was completed with the combination of pseudo-haptic feedback and force feedback. Participants were asked to palpate the virtual soft tissue block with hidden nodules by using the combined feedback method and then asked to indicate the different positions where they believed to have found the hard nodules and timed until completion.