Integrated STEM education is increasingly present in classrooms and in educational research, as it is proposed as a possible strategy to improve the problems of students’ lack of interest in scientific–technological disciplines. However, this increased interest in STEM education has been paralleled by a loss of cohesion in the interpretations of its theoretical basis and by an ongoing discussion on integrated STEM education’s foundations, making its understanding, translation into real projects, and evaluation difficult to undertake. Published articles defining a STEM theoretical framework have different descriptions, so the aim of this systematic literature review is to analyse these explanations and compare them with each other. Following the PRISMA 2020 guidelines, 27 articles of interest about STEM and STEAM education were obtained and analysed with a focus on the principles and characteristics described in the texts. After organising the information and analysing the similarities and differences in the principles and characteristics, we concluded that there is great consensus on the principles of “integration”, “real-world problems”, “inquiry”, “design”, and “teamwork”. Nonetheless, this review identifies areas of discussion regarding both the principles and their characteristics that invite further analysis to refine our understanding of what integrated STEM education should entail.

Objective: Electrically evoked auditory steady-state responses (EASSRs) are neural potentials measured in the electroencephalogram (EEG) in response to periodic pulse trains presented, for example, through a cochlear implant (CI). EASSRs could potentially be used for objective CI fitting. However, EEG signals are contaminated with electrical CI artifacts. In this paper, we characterized the CI artifacts for monopolar mode stimulation and evaluated at which pulse rate, linear interpolation over the signal part contaminated with CI artifact is successful. Methods: CI artifacts were characterized by means of their amplitude growth functions and duration. Results: CI artifact durations were between 0.7 and 1.7 ms, at contralateral recording electrodes. At ipsilateral recording electrodes, CI artifact durations are range from 0.7 to larger than 2 ms. Conclusion: At contralateral recording electrodes, the artifact was shorter than the interpulse interval across subjects for 500 pps, which was not always the case for 900 pps. Significance: CI artifact-free EASSRs are crucial for reliable CI fitting and neuroscience research. The CI artifact has been characterized and linear interpolation allows to remove it at contralateral recording electrodes for stimulation at 500 pps.

Cochlear implant (CI) stimulation artifacts are currently removed from electrically evoked steady-state response (EASSR) measurements based on a linear interpolation (LI) over the artifact-contaminated signal parts. LI is only successful if CI stimulation artifacts are shorter than the interpulse interval, i.e., for contralateral channels and stimulation pulse rates up to 500 pulses per second (pps). The objective of this paper is to develop and evaluate a template subtraction (TS) method to remove continuous CI stimulation artifacts in order to accurately measure EASSRs. The template construction (TC) is based on an EEG recording containing CI stimulation artifacts but no synchronous neural response. The constructed templates are subtracted from the recording of interest. Response amplitudes and latencies are compared for the TS and LI method, and for different TC durations. The response amplitudes and latencies in contralateral channels are the same after TS and LI, as expected. In ipsilateral channels, response amplitudes and latencies are within the expected range only after TS. The TC duration can be reduced from 5 min to 1 min without a significant effect on response latency. TS with a TC duration of only 1 min allows to remove all CI stimulation artifacts in individual contra- and ipsilateral EEG recording channels.

Objective . Electrically evoked auditory steady-state responses (EASSRs) are potentially useful for objective cochlear implant (CI) fitting and follow-up of the auditory maturation in infants and children with a CI. EASSRs are recorded in the electro-encephalogram (EEG) in response to electrical stimulation with continuous pulse trains, and are distorted by significant CI artifacts related to this electrical stimulation. The aim of this study is to evaluate a CI artifacts attenuation method based on independent component analysis (ICA) for three EASSR datasets. Approach . ICA has often been used to remove CI artifacts from the EEG to record transient auditory responses, such as cortical evoked auditory potentials. Independent components (ICs) corresponding to CI artifacts are then often manually identified. In this study, an ICA based CI artifacts attenuation method was developed and evaluated for EASSR measurements with varying CI artifacts and EASSR characteristics. Artifactual ICs were automatically identified based on their spectrum. Main results . For 40 Hz amplitude modulation (AM) stimulation at comfort level, in high SNR recordings, ICA succeeded in removing CI artifacts from all recording channels, without distorting the EASSR. For lower SNR recordings, with 40 Hz AM stimulation at lower levels, or 90 Hz AM stimulation, ICA either distorted the EASSR or could not remove all CI artifacts in most subjects, except for two of the seven subjects tested with low level 40 Hz AM stimulation. Noise levels were reduced after ICA was applied, and up to 29 ICs were rejected, suggesting poor ICA separation quality. Significance . We hypothesize that ICA is capable of separating CI artifacts and EASSR in case the contralateral hemisphere is EASSR dominated. For small EASSRs or large CI artifact amplitudes, ICA separation quality is insufficient to ensure complete CI artifacts attenuation without EASSR distortion.

Graduates with a STEM profile are in great demand, yet the outflow from these fields of study is highly insufficient. This is partly due to the fragmented way STEM learning content is taught in secondary education. Although the problem can be mitigated with the use of integrated STEM education (i.e., iSTEM), teachers are often unfamiliar with this type of education. To support teachers in implementing high-quality iSTEM education, a digital collaborative learning environment called “CODEM for iSTEM” was created. This study examined to what extent student teachers were immersed in six key principles of iSTEM education through cooperative design of iSTEM learning tools in multidisciplinary teams, namely “problem-centered learning”, “integration of different STEM disciplines”, “modeling”, “inquiry-based learning”, “design-based learning”, and “cooperative learning”.