Q.1 Which type of sensor is most commonly used to detect muscle activity for myoelectric prosthetic control?
Piezoelectric sensor
Electromyography (EMG) electrode
Thermistor
Hall-effect sensor
Explanation - EMG electrodes measure the electrical potentials generated by muscle fibers, providing the signal needed to control myoelectric prostheses.
Correct answer is: Electromyography (EMG) electrode
Q.2 What does the acronym BCI stand for in neural rehabilitation?
Brain-Computer Interface
Biofeedback Control Integration
Biosensor Connectivity Index
Basic Cognitive Input
Explanation - BCI refers to systems that translate brain signals into commands for external devices, enabling communication or control for users with severe motor impairments.
Correct answer is: Brain-Computer Interface
Q.3 In sensory substitution devices, visual information is often translated into which type of sensory modality?
Olfactory
Auditory
Gustatory
Thermal
Explanation - Auditory substitution converts visual data (e.g., distance, shape) into sound patterns, allowing blind users to perceive spatial information through hearing.
Correct answer is: Auditory
Q.4 Which neural signal is most frequently used in non‑invasive BCI systems for cursor control?
Local field potentials (LFP)
Spiking activity
Electroencephalography (EEG) mu rhythm
Magnetoencephalography (MEG) beta rhythm
Explanation - The mu rhythm (8‑13 Hz) over sensorimotor cortex modulates with imagined movement, making it suitable for EEG‑based BCI control.
Correct answer is: Electroencephalography (EEG) mu rhythm
Q.5 Which of the following is a major advantage of using intraneural electrodes over surface electrodes for sensory feedback?
Lower surgical risk
Higher spatial resolution of stimulation
Longer battery life
Simpler signal processing
Explanation - Intraneural electrodes are inserted into peripheral nerves, allowing precise activation of specific nerve fibers, which improves the quality of artificial sensory feedback.
Correct answer is: Higher spatial resolution of stimulation
Q.6 The term "phantom limb pain" is most closely associated with which phenomenon?
Cortical re‑organization after amputation
Peripheral nerve regeneration
Spinal cord injury
Muscle atrophy
Explanation - After amputation, the brain's somatosensory map can reorganize, leading to the perception of pain in the missing limb.
Correct answer is: Cortical re‑organization after amputation
Q.7 Which of the following algorithms is commonly used for classifying EEG signals in BCI applications?
K‑means clustering
Support Vector Machine (SVM)
Dijkstra's algorithm
QuickSort
Explanation - SVMs are effective for separating high‑dimensional EEG feature spaces, making them popular in BCI classification tasks.
Correct answer is: Support Vector Machine (SVM)
Q.8 In a vibrotactile feedback system for a prosthetic hand, what parameter mainly determines the perceived intensity of vibration?
Frequency of vibration
Amplitude of vibration
Waveform shape
Duty cycle
Explanation - Higher amplitudes produce stronger tactile sensations, while frequency influences the quality (e.g., buzzing vs. tapping).
Correct answer is: Amplitude of vibration
Q.9 Which component of the nervous system is primarily targeted by transcutaneous electrical nerve stimulation (TENS) for pain relief?
Motor neurons
Sensory afferent fibers
Autonomic ganglia
Cerebellar Purkinje cells
Explanation - TENS activates large-diameter sensory fibers, which can inhibit nociceptive signals via the gate control theory.
Correct answer is: Sensory afferent fibers
Q.10 Which material is most suitable for flexible, skin‑conforming electrodes used in EEG caps?
Silicon carbide
Polyimide
Stainless steel
Gold foil
Explanation - Polyimide is thin, flexible, and biocompatible, making it ideal for conformal electrodes that maintain good contact with the scalp.
Correct answer is: Polyimide
Q.11 What is the primary purpose of a 'sensory substitution' device for individuals with visual impairment?
To restore retinal function
To replace vision with auditory or tactile cues
To improve eye‑muscle coordination
To increase intra‑ocular pressure
Explanation - Sensory substitution provides alternative sensory channels (e.g., sound, touch) to convey visual information, enabling perception without restoring sight.
Correct answer is: To replace vision with auditory or tactile cues
Q.12 Which frequency band of EEG is most closely linked to attention and active processing?
Delta (0.5‑4 Hz)
Theta (4‑8 Hz)
Alpha (8‑13 Hz)
Beta (13‑30 Hz)
Explanation - Beta activity increases during focused mental activity and sensorimotor processing.
Correct answer is: Beta (13‑30 Hz)
Q.13 In the context of neural prostheses, what does the term "closed‑loop" refer to?
A system that only records neural activity
A system that provides both recording and stimulation based on feedback
A prosthetic that operates without power
A device that uses a single electrode
Explanation - Closed‑loop prostheses monitor neural signals and adjust stimulation in real time, improving functionality and adaptability.
Correct answer is: A system that provides both recording and stimulation based on feedback
Q.14 Which of the following is a key challenge when designing implantable neural interfaces for long‑term use?
High power consumption
Signal attenuation due to skull thickness
Biocompatibility and tissue response
Limited Bluetooth range
Explanation - Implanted devices must avoid inflammation, scar tissue formation, and corrosion, which can degrade signal quality over time.
Correct answer is: Biocompatibility and tissue response
Q.15 What does the term "somatosensory evoked potential (SEP)" describe?
Electrical activity generated by the heart
Brain response to a tactile stimulus
Magnetic field fluctuations in the scalp
Voltage changes in muscle fibers
Explanation - SEPs are recorded from the cortex following peripheral sensory stimulation and are used to assess the integrity of somatosensory pathways.
Correct answer is: Brain response to a tactile stimulus
Q.16 Which neural pathway primarily carries fine touch and proprioceptive information to the brain?
Spinothalamic tract
Dorsal column‑medial lemniscal pathway
Corticospinal tract
Rubrospinal tract
Explanation - This pathway transmits discriminative touch and proprioception from peripheral receptors to the thalamus and cortex.
Correct answer is: Dorsal column‑medial lemniscal pathway
Q.17 Which of the following is a typical metric used to evaluate the performance of a BCI spelling system?
Bit rate (bits per minute)
Battery voltage
Signal‑to‑noise ratio of EMG
Latency of haptic feedback
Explanation - Bit rate quantifies the speed and accuracy of information transfer in a BCI communication system.
Correct answer is: Bit rate (bits per minute)
Q.18 In a functional electrical stimulation (FES) system for gait rehabilitation, which muscle group is typically stimulated first to initiate stepping?
Hamstrings
Gluteus maximus
Quadriceps
Tibialis anterior
Explanation - Activating the hip extensors (gluteus maximus) helps initiate the stance phase and provides forward propulsion.
Correct answer is: Gluteus maximus
Q.19 What is the main advantage of using a high‑density EEG cap (e.g., 256 channels) over a low‑density cap (e.g., 32 channels) in neural rehabilitation research?
Lower cost
Reduced setup time
Higher spatial resolution of brain activity
Longer battery life
Explanation - More electrodes provide finer mapping of cortical activity, improving source localization and decoding accuracy.
Correct answer is: Higher spatial resolution of brain activity
Q.20 Which of the following best describes "neuroplasticity"?
The ability of neurons to generate electricity
The capacity of the nervous system to reorganize its structure and function
The rate at which nerve impulses travel
The resistance of neural tissue to electrical current
Explanation - Neuroplasticity underlies learning and recovery after injury, allowing the brain to form new connections.
Correct answer is: The capacity of the nervous system to reorganize its structure and function
Q.21 Which type of electrode is most appropriate for non‑invasive recording of brain activity during a visual evoked potential (VEP) test?
Screw electrode
Needle electrode
Surface (gel) electrode
Intracortical microelectrode
Explanation - Surface electrodes with conductive gel provide good contact for recording scalp potentials without penetrating tissue.
Correct answer is: Surface (gel) electrode
Q.22 In a brain‑spine interface designed to restore hand function after spinal cord injury, which signal is typically decoded to generate motor commands?
Epidural spinal cord potentials
Cortical motor‑related EEG rhythms
Peripheral nerve action potentials
Heart rate variability
Explanation - Decoding motor intentions from cortical EEG allows translation into stimulation patterns that activate spinal circuits below the injury.
Correct answer is: Cortical motor‑related EEG rhythms
Q.23 Which of the following describes a "haptic glove" used in sensory rehabilitation?
A glove that provides visual feedback via LEDs
A glove that delivers patterned vibrations to fingertips
A glove that monitors heart rate
A glove that records EEG signals
Explanation - Haptic gloves use actuators to create tactile sensations, helping users regain fine‑touch perception or control prosthetic devices.
Correct answer is: A glove that delivers patterned vibrations to fingertips
Q.24 What is the purpose of a "ground electrode" in EEG recordings?
To amplify the signal
To provide a reference potential and reduce noise
To stimulate the brain
To measure muscle activity
Explanation - A ground electrode stabilizes the electrical baseline and minimizes common‑mode interference.
Correct answer is: To provide a reference potential and reduce noise
Q.25 Which of the following is a common method for reducing motion artifacts in wearable EEG systems?
Increasing electrode impedance
Applying a high‑pass filter at 0.5 Hz
Using active shielding and adaptive filtering
Reducing sampling rate to 10 Hz
Explanation - Active shielding minimizes external interference, while adaptive filters can dynamically suppress motion‑related noise.
Correct answer is: Using active shielding and adaptive filtering
Q.26 In the context of prosthetic limb control, what does the term "synergy" refer to?
A group of muscles that work together to produce a movement
The battery life of the prosthetic
The visual appearance of the device
The cost of manufacturing
Explanation - Synergies simplify control by allowing the prosthetic to interpret coordinated muscle activation patterns as intended gestures.
Correct answer is: A group of muscles that work together to produce a movement
Q.27 Which imaging modality provides the highest temporal resolution for monitoring brain activity during neurorehabilitation tasks?
Functional MRI (fMRI)
Positron Emission Tomography (PET)
Electroencephalography (EEG)
Diffusion Tensor Imaging (DTI)
Explanation - EEG can capture neural dynamics on the order of milliseconds, far faster than hemodynamic‑based methods like fMRI.
Correct answer is: Electroencephalography (EEG)
Q.28 What is the main function of a "sensory feedback controller" in a myoelectric prosthetic hand?
To amplify EMG signals
To adjust grip force based on tactile sensor input
To power the prosthetic battery
To provide visual cues to the user
Explanation - Sensory feedback controllers use data from force or pressure sensors to modulate motor commands, preventing over‑gripping.
Correct answer is: To adjust grip force based on tactile sensor input
Q.29 Which frequency band is most commonly targeted for sensory feedback via transcranial alternating current stimulation (tACS)?
Delta (1‑4 Hz)
Alpha (8‑12 Hz)
Gamma (30‑80 Hz)
Beta (13‑30 Hz)
Explanation - Alpha tACS can modulate cortical excitability associated with sensory perception and attention.
Correct answer is: Alpha (8‑12 Hz)
Q.30 A cochlear implant bypasses which part of the auditory system?
Outer ear
Middle ear
Cochlea
Auditory cortex
Explanation - The implant directly stimulates the auditory nerve, replacing the function of the damaged cochlear hair cells.
Correct answer is: Cochlea
Q.31 Which type of stimulation is most appropriate for restoring a sense of pressure on a prosthetic limb?
Electrical stimulation of motor nerves
Vibrotactile stimulation of skin
Optogenetic stimulation of visual cortex
Magnetic stimulation of the spinal cord
Explanation - Vibrotactile actuators can simulate pressure cues on the skin, conveying tactile information from the prosthetic.
Correct answer is: Vibrotactile stimulation of skin
Q.32 What does the term "latency" refer to in the context of neural signal processing?
The amplitude of the signal
The time delay between stimulus and response
The power consumption of the device
The number of electrodes used
Explanation - Latency measures how quickly the system detects or reacts to a neural event, critical for real‑time applications.
Correct answer is: The time delay between stimulus and response
Q.33 Which of the following is a key benefit of using machine learning for decoding motor intentions from EMG signals?
Eliminates the need for electrodes
Improves classification accuracy across users and conditions
Reduces the size of the prosthetic hand
Increases the battery life of the device
Explanation - Machine learning algorithms can adapt to variability in EMG patterns, leading to more reliable control.
Correct answer is: Improves classification accuracy across users and conditions
Q.34 Which of the following best describes a "neuromorphic" processor used in sensory rehabilitation devices?
A processor that mimics the architecture of the human brain
A high‑speed digital signal processor
A low‑power analog amplifier
A standard microcontroller with Bluetooth
Explanation - Neuromorphic chips emulate neural networks in hardware, enabling efficient, low‑latency processing of sensory data.
Correct answer is: A processor that mimics the architecture of the human brain
Q.35 In a visual prosthesis (retinal implant), which component directly converts light into electrical signals?
Photodiode array
Microphone
Accelerometer
Force sensor
Explanation - Photodiodes generate currents in response to light, stimulating the remaining retinal cells.
Correct answer is: Photodiode array
Q.36 Which of the following is a major limitation of current non‑invasive BCI systems?
They require surgical implantation
Low spatial resolution of recorded signals
High risk of infection
Limited battery life
Explanation - Non‑invasive BCIs (e.g., EEG) capture signals from the scalp, which reduces the ability to isolate activity from specific cortical areas.
Correct answer is: Low spatial resolution of recorded signals
Q.37 Which type of sensor is commonly used in exoskeletons to detect joint angles?
Hall‑effect sensor
Accelerometer
Gyroscope
Potentiometer
Explanation - Potentiometers provide accurate angular position measurements, essential for controlling joint actuation in exoskeletons.
Correct answer is: Potentiometer
Q.38 What is the main advantage of using a "dual‑mode" BCI that combines EEG and EMG signals?
Reduced cost of hardware
Increased robustness to signal loss
Simpler signal processing algorithms
Higher power consumption
Explanation - Combining EEG (brain) and EMG (muscle) signals provides redundancy, improving reliability when one modality degrades.
Correct answer is: Increased robustness to signal loss
Q.39 Which of the following is a typical symptom of sensory ataxia?
Loss of muscle strength
Impaired coordination despite normal strength
Severe headache
Visual field loss
Explanation - Sensory ataxia results from loss of proprioceptive feedback, causing unsteady movements even when muscles are strong.
Correct answer is: Impaired coordination despite normal strength
Q.40 In a prosthetic hand, what is the purpose of a "force sensor" placed on the fingertips?
To measure grip force for feedback control
To detect temperature changes
To sense ambient light
To monitor battery voltage
Explanation - Force sensors enable the prosthetic to adjust grasp strength and prevent object damage or slippage.
Correct answer is: To measure grip force for feedback control
Q.41 Which of the following best defines the term "sensory gating"?
The process of amplifying all sensory inputs
The brain’s mechanism to filter out irrelevant sensory information
The generation of new sensory pathways
The degeneration of sensory neurons
Explanation - Sensory gating helps prevent overload by suppressing unnecessary stimuli, a principle used in neurorehabilitation to focus attention.
Correct answer is: The brain’s mechanism to filter out irrelevant sensory information
Q.42 Which of the following technologies is most suitable for providing real‑time visual feedback of gait symmetry during rehabilitation?
Infrared motion capture system
Surface EMG recording
EEG headset
Heart rate monitor
Explanation - Infrared cameras can track limb positions with high precision, allowing immediate visual feedback on gait patterns.
Correct answer is: Infrared motion capture system
Q.43 What does the term "haptic illusion" refer to in sensory rehabilitation?
A false visual perception created by sound
A sensation of touch produced without actual mechanical stimulation
A memory of previous pain
An auditory hallucination
Explanation - Haptic illusions can be generated by electrical stimulation patterns that trick the brain into feeling tactile sensations.
Correct answer is: A sensation of touch produced without actual mechanical stimulation
Q.44 Which neural structure is primarily responsible for integrating somatosensory information before it reaches the cortex?
Thalamus
Basal ganglia
Cerebellum
Hippocampus
Explanation - The thalamus acts as a relay station, processing and forwarding sensory data to appropriate cortical areas.
Correct answer is: Thalamus
Q.45 When designing a wearable tactile display, which factor most influences the user's perception of spatial patterns?
Actuator voltage
Actuator spacing (density)
Battery weight
Wireless range
Explanation - Higher density allows finer resolution of tactile patterns, improving the ability to convey detailed information.
Correct answer is: Actuator spacing (density)
Q.46 Which of the following best describes a "somatosensory cortex" lesion effect?
Loss of language comprehension
Impaired ability to feel touch and proprioception
Inability to move the eyes
Loss of auditory perception
Explanation - Damage to the primary somatosensory cortex disrupts processing of tactile and proprioceptive inputs.
Correct answer is: Impaired ability to feel touch and proprioception
Q.47 In the context of neurorehabilitation, what is the purpose of "mirror therapy"?
To provide visual feedback of the affected limb’s movement
To stimulate auditory pathways
To improve cardiovascular fitness
To measure blood glucose levels
Explanation - Patients watch the reflection of their unaffected limb moving, which can activate mirror neurons and promote motor recovery.
Correct answer is: To provide visual feedback of the affected limb’s movement
Q.48 Which type of neural interface is specifically designed to record from peripheral nerves?
ECoG grid
Microelectrode array (MEA)
Cuff electrode
EEG cap
Explanation - Cuff electrodes wrap around peripheral nerves, allowing chronic recording and stimulation of nerve activity.
Correct answer is: Cuff electrode
Q.49 What is the primary function of the "posterior parietal cortex" in sensorimotor integration?
Regulating heart rate
Processing visual color information
Integrating sensory input to guide movements
Generating speech sounds
Explanation - The posterior parietal cortex combines visual, somatosensory, and auditory data to plan and adjust actions.
Correct answer is: Integrating sensory input to guide movements
Q.50 Which of the following is a common metric for evaluating the smoothness of a prosthetic hand’s grasp?
Root‑mean‑square error (RMSE)
Jerk index
Signal‑to‑noise ratio
Battery discharge rate
Explanation - Jerk (the derivative of acceleration) quantifies motion smoothness; lower jerk indicates smoother grasp trajectories.
Correct answer is: Jerk index
Q.51 Which of the following best explains why tactile feedback improves prosthetic embodiment?
It reduces the weight of the prosthesis
It provides a sense of agency and ownership through sensory integration
It increases the visual appeal of the device
It eliminates the need for batteries
Explanation - When users receive touch sensations from the prosthesis, the brain integrates these signals, fostering a feeling that the limb is part of the body.
Correct answer is: It provides a sense of agency and ownership through sensory integration
Q.52 Which of the following techniques can be used to enhance the signal quality of surface EMG recordings?
Increasing inter‑electrode distance
Skin preparation (cleaning and abrasion)
Using high‑impedance electrodes
Reducing sampling frequency
Explanation - Proper skin preparation reduces impedance and improves the signal-to-noise ratio of EMG recordings.
Correct answer is: Skin preparation (cleaning and abrasion)
Q.53 What does the term "neuroprosthesis" specifically refer to?
A device that replaces lost neural tissue with synthetic material
A prosthetic that restores lost sensory or motor function via neural interfacing
A cosmetic limb with realistic appearance
A surgical technique for bone repair
Explanation - Neuroprostheses connect to the nervous system to re‑establish communication pathways lost due to injury or disease.
Correct answer is: A prosthetic that restores lost sensory or motor function via neural interfacing
Q.54 Which of the following is a key advantage of using a "soft robotic" exosuit for gait rehabilitation?
Higher torque output than rigid exoskeletons
Greater comfort and reduced joint restriction
Simplified surgical implantation
Ability to function without power
Explanation - Soft exosuits use textiles and compliant actuators, allowing natural movement while providing assistance.
Correct answer is: Greater comfort and reduced joint restriction
Q.55 In the context of visual prostheses, what is the function of a "phosphene"?
A light‑induced visual percept caused by electrical stimulation
A type of retinal cell
A measure of battery capacity
An auditory illusion
Explanation - Phosphenes are perceived spots of light generated when the visual cortex or retina is electrically stimulated, used as a basic visual signal in prosthetic systems.
Correct answer is: A light‑induced visual percept caused by electrical stimulation
Q.56 Which of the following best describes the principle of "stochastic resonance" in sensory rehabilitation?
Adding random noise can improve detection of weak sensory signals
Reducing noise always improves signal clarity
Increasing signal amplitude always yields better perception
Noise is detrimental to all neural processing
Explanation - A small amount of noise can enhance the detection of sub‑threshold stimuli by pushing them over the neural firing threshold.
Correct answer is: Adding random noise can improve detection of weak sensory signals
Q.57 Which of the following is the primary reason for using a "band‑pass filter" (1–40 Hz) on EEG data for motor imagery BCI?
To remove motion artifacts only
To isolate the frequency bands containing motor‑related rhythms
To increase the amplitude of all signals
To reduce power consumption
Explanation - Motor imagery modulates mu (8‑13 Hz) and beta (13‑30 Hz) rhythms; band‑pass filtering preserves these while discarding irrelevant frequencies.
Correct answer is: To isolate the frequency bands containing motor‑related rhythms
Q.58 What is the main purpose of a "force‑feedback" loop in an exoskeleton for upper‑limb rehabilitation?
To adjust assistance based on the user's exerted force
To monitor heart rate
To change the color of the device
To synchronize with a smartphone
Explanation - Force‑feedback enables the exoskeleton to provide just enough support, encouraging active participation and preventing over‑assistance.
Correct answer is: To adjust assistance based on the user's exerted force
Q.59 Which of the following is a typical challenge when using optical fiber sensors for measuring strain in wearable rehabilitation devices?
High power consumption
Sensitivity to temperature variations
Inability to detect small deformations
Heavy weight
Explanation - Fiber Bragg grating sensors can be affected by temperature, requiring compensation algorithms for accurate strain measurement.
Correct answer is: Sensitivity to temperature variations
Q.60 Which of the following best defines "sensory substitution" in the context of neurorehabilitation?
Replacing a damaged sensory organ with a prosthetic that mimics its function
Using one sensory modality to convey information normally provided by another
Enhancing the remaining senses through medication
Training the brain to ignore missing sensory inputs
Explanation - Sensory substitution transforms data (e.g., visual) into another channel (e.g., tactile) to compensate for loss.
Correct answer is: Using one sensory modality to convey information normally provided by another
Q.61 Which type of signal processing technique is commonly employed to extract features from EMG for prosthetic control?
Fast Fourier Transform (FFT)
Principal Component Analysis (PCA)
Linear Predictive Coding (LPC)
Wavelet transform
Explanation - Wavelet analysis captures both time and frequency information of non‑stationary EMG signals, making it suitable for real‑time feature extraction.
Correct answer is: Wavelet transform
Q.62 In a tactile display, what does the term "refresh rate" refer to?
How often the device updates the vibration patterns per second
The battery charging speed
The number of sensors on the device
The maximum voltage the actuators can handle
Explanation - Higher refresh rates allow smoother and more dynamic tactile sensations, improving the fidelity of feedback.
Correct answer is: How often the device updates the vibration patterns per second
Q.63 Which neural pathway is primarily targeted by functional electrical stimulation (FES) for restoring hand grasp after stroke?
Corticospinal tract
Spinocerebellar tract
Reticulospinal tract
Vestibulospinal tract
Explanation - FES aims to activate motor neurons that are part of the corticospinal pathway, which controls voluntary hand movements.
Correct answer is: Corticospinal tract
Q.64 What is the primary purpose of a "bias‑tee" in a neural recording circuit?
To separate AC neural signals from DC bias voltage
To increase the amplitude of the signal
To provide wireless communication
To store data in memory
Explanation - A bias‑tee allows simultaneous delivery of DC bias to an electrode while passing AC neural activity to the amplifier.
Correct answer is: To separate AC neural signals from DC bias voltage
Q.65 Which of the following is an example of a "closed‑loop" sensory feedback system for a prosthetic foot?
A pressure sensor that modulates vibration intensity on the residual limb
A battery indicator LED
A GPS tracker for location awareness
A microphone that records footsteps
Explanation - The pressure sensor measures ground contact and feeds back tactile cues, enabling the user to adjust gait in real time.
Correct answer is: A pressure sensor that modulates vibration intensity on the residual limb
Q.66 Which of the following best describes "neurofeedback" as used in rehabilitation?
Providing auditory cues to improve hearing
Training patients to modify their own brain activity using real‑time feedback
Delivering medication through a neural implant
Using prosthetic limbs to replace missing body parts
Explanation - Neurofeedback presents users with live representations of their neural signals, enabling self‑regulation of brain activity for therapeutic benefit.
Correct answer is: Training patients to modify their own brain activity using real‑time feedback
Q.67 In a cortical visual prosthesis, which cortical area is typically targeted for stimulation?
Primary visual cortex (V1)
Primary auditory cortex (A1)
Primary motor cortex (M1)
Somatosensory cortex (S1)
Explanation - V1 processes basic visual information; stimulating it can evoke phosphenes that the brain interprets as visual percepts.
Correct answer is: Primary visual cortex (V1)
Q.68 Which of the following is a key limitation of using surface EMG for controlling a high‑DOF (degrees of freedom) prosthetic arm?
Limited number of independent signal sources
Excessive power consumption
Inability to detect any muscle activity
High surgical risk
Explanation - Surface EMG provides a limited set of distinguishable patterns, making it challenging to independently control many joints.
Correct answer is: Limited number of independent signal sources
Q.69 Which of the following sensor technologies is most suitable for detecting skin stretch in a wearable rehabilitation sleeve?
Capacitive strain gauge
Thermocouple
Piezoelectric speaker
Photodiode
Explanation - Capacitive sensors change capacitance with deformation, providing accurate measurement of skin stretch.
Correct answer is: Capacitive strain gauge
Q.70 What is the purpose of "artifact rejection" in EEG‑based BCI systems?
To enhance the battery life of the device
To eliminate non‑brain signals such as eye blinks or muscle activity
To increase the sampling rate
To improve wireless transmission speed
Explanation - Artifact rejection algorithms filter out noise sources, ensuring that only neural activity is used for control.
Correct answer is: To eliminate non‑brain signals such as eye blinks or muscle activity
Q.71 Which of the following best describes a "neurorobotic" system?
A robot that can operate underwater
A robotic device that interacts directly with the nervous system
A robot used for industrial assembly
A robot that can fly autonomously
Explanation - Neurorobotics combines robotics with neural interfacing to restore or augment motor and sensory functions.
Correct answer is: A robotic device that interacts directly with the nervous system
Q.72 Which of the following is a standard metric for evaluating the accuracy of a BCI classifier?
Mean squared error (MSE)
Confusion matrix
Battery voltage
Signal attenuation
Explanation - A confusion matrix displays true vs. predicted classes, allowing calculation of accuracy, precision, recall, etc.
Correct answer is: Confusion matrix
Q.73 What is the main advantage of using a "soft pneumatic actuator" in a wearable exosuit?
Higher torque than electric motors
Lightweight and compliant interaction with the user
No need for any control system
Unlimited power supply
Explanation - Soft pneumatic actuators can inflate/deflate, providing assistance while remaining flexible and comfortable.
Correct answer is: Lightweight and compliant interaction with the user
Q.74 In a sensory neurorehabilitation study, a significant increase in the "P300" component of an ERP indicates:
Improved motor strength
Enhanced attentional processing to a target stimulus
Reduced visual acuity
Higher heart rate variability
Explanation - The P300 is an event‑related potential that reflects attention and stimulus evaluation.
Correct answer is: Enhanced attentional processing to a target stimulus
Q.75 Which of the following is a key factor in designing a user‑friendly interface for a BCI‑controlled wheelchair?
Complex command set with many options
Simple, intuitive control mappings with visual feedback
High‑frequency auditory alarms
Frequent reboot requirements
Explanation - Ease of use and clear feedback reduce cognitive load and improve safety for users with limited motor function.
Correct answer is: Simple, intuitive control mappings with visual feedback
Q.76 Which of the following best describes the concept of "sensory integration therapy"?
Training patients to ignore sensory input
Providing controlled sensory experiences to improve processing and response
Using medication to enhance sensory perception
Surgically implanting new sensory receptors
Explanation - Therapy uses graded sensory stimuli to help the nervous system better integrate and respond to sensory information.
Correct answer is: Providing controlled sensory experiences to improve processing and response
Q.77 What is the primary role of a "microcontroller" in a wearable haptic device?
To store large datasets
To generate and time the activation of tactile actuators
To provide power to the device
To act as a wireless router
Explanation - Microcontrollers execute firmware that drives haptic patterns based on sensor input or pre‑programmed sequences.
Correct answer is: To generate and time the activation of tactile actuators
Q.78 Which of the following best characterizes the "gate control theory" of pain?
Pain signals are amplified by the spinal cord
Non‑painful stimuli can inhibit pain transmission at the spinal level
Pain is solely a psychological construct
Pain signals are only processed in the cortex
Explanation - Activating large‑diameter fibers (e.g., via vibration) can close the spinal gate, reducing pain perception.
Correct answer is: Non‑painful stimuli can inhibit pain transmission at the spinal level
Q.79 Which of the following is a common approach to reduce power consumption in implantable neural stimulators?
Increasing stimulation frequency
Using charge‑balanced biphasic pulses
Operating at higher voltages
Adding redundant circuitry
Explanation - Biphasic pulses prevent net charge buildup, allowing lower voltage operation and extending battery life.
Correct answer is: Using charge‑balanced biphasic pulses
Q.80 In the context of prosthetic limb control, what does "proportional control" mean?
The prosthetic moves at a fixed speed regardless of input
The speed/force of the prosthetic is proportional to the amplitude of the control signal
The prosthetic only moves in binary on/off states
The prosthetic uses proportional‑integral‑derivative (PID) control loops
Explanation - Proportional control maps the magnitude of EMG or other signals to the output speed or grip force, offering smoother movement.
Correct answer is: The speed/force of the prosthetic is proportional to the amplitude of the control signal
Q.81 Which type of neural recording provides the highest spatial resolution?
EEG
ECoG (electrocorticography)
Intracortical microelectrode array
MEG (magnetoencephalography)
Explanation - Microelectrode arrays can record from individual neurons, offering micrometer‑scale resolution.
Correct answer is: Intracortical microelectrode array
Q.82 What is the main functional purpose of the "muscle spindle" in the proprioceptive system?
Detecting changes in muscle length and speed of stretch
Generating motor commands
Transmitting visual information
Regulating blood pressure
Explanation - Muscle spindles provide feedback about limb position and movement, essential for proprioception.
Correct answer is: Detecting changes in muscle length and speed of stretch
Q.83 Which of the following is a primary advantage of using "optogenetics" in animal models of neural rehabilitation?
Non‑invasive stimulation of deep brain structures
Precise control of specific neuronal populations with light
Reduced need for surgical procedures
Ability to stimulate muscles directly
Explanation - Optogenetics allows targeted activation/inhibition of genetically modified neurons using specific wavelengths of light.
Correct answer is: Precise control of specific neuronal populations with light
Q.84 Which of the following signal characteristics is most commonly used to differentiate between different imagined movements in an EEG‑based BCI?
Signal amplitude at 60 Hz
Event‑related desynchronization (ERD) in the mu/beta band
Baseline DC offset
Signal phase at 1 Hz
Explanation - ERD reflects a decrease in power of sensorimotor rhythms during imagined movement, serving as a reliable BCI feature.
Correct answer is: Event‑related desynchronization (ERD) in the mu/beta band
Q.85 In a prosthetic hand with sensory feedback, which type of stimulation is most often used to convey grip force to the user?
Electrical stimulation of the optic nerve
Vibrotactile stimulation on the forearm
Auditory tones through a speaker
Temperature changes on the palm
Explanation - Vibrotactile cues can be mapped to grip force levels, providing intuitive feedback without invasive procedures.
Correct answer is: Vibrotactile stimulation on the forearm
Q.86 Which of the following best describes the role of "neurotrophic factors" in neural rehabilitation?
They provide electrical stimulation to neurons
They promote growth and survival of neurons after injury
They block synaptic transmission
They act as neurotransmitters
Explanation - Neurotrophic factors such as BDNF support neuronal repair and plasticity, enhancing rehabilitation outcomes.
Correct answer is: They promote growth and survival of neurons after injury
Q.87 Which of the following is an advantage of using a "flexible printed circuit board (FPCB)" for wearable EEG caps?
Higher thermal resistance
Increased rigidity
Conformability to curved surfaces
Reduced signal bandwidth
Explanation - FPCBs can bend to match the shape of the head, improving electrode contact and user comfort.
Correct answer is: Conformability to curved surfaces
Q.88 What does the "latency" of a haptic actuator refer to?
The time between command issuance and tactile stimulus onset
The maximum vibration intensity
The battery life of the actuator
The frequency of the vibration
Explanation - Low latency is crucial for timely feedback, especially in closed‑loop control systems.
Correct answer is: The time between command issuance and tactile stimulus onset
Q.89 Which of the following is a typical use case for "electrotactile" stimulation in rehabilitation?
Providing visual cues for navigation
Delivering tactile sensations via skin electrodes
Measuring blood oxygen levels
Generating magnetic fields for imaging
Explanation - Electrotactile stimulation activates cutaneous nerves to create perceivable touch sensations for feedback.
Correct answer is: Delivering tactile sensations via skin electrodes
Q.90 In a neural prosthesis for restoring hand sensation, what is the primary benefit of delivering stimulation at the "somatosensory cortex" rather than peripheral nerves?
Reduced surgical complexity
Higher fidelity of tactile perception
Lower power consumption
Elimination of any need for electrodes
Explanation - Cortical stimulation can directly evoke complex tactile percepts without the variability of peripheral nerve interfaces.
Correct answer is: Higher fidelity of tactile perception
Q.91 Which of the following best explains why "adaptive filtering" is important in wearable EEG for rehabilitation?
It automatically adjusts filter parameters to compensate for changing noise conditions
It increases the size of the electrodes
It reduces the need for a power source
It eliminates the need for signal amplification
Explanation - Adaptive filters can track and suppress time‑varying artifacts such as motion or muscle activity, preserving neural signals.
Correct answer is: It automatically adjusts filter parameters to compensate for changing noise conditions
Q.92 Which of the following is a major factor influencing the comfort of a long‑term wearable prosthetic socket?
Weight of the microcontroller
Thermal conductivity of the liner material
Number of embedded LEDs
Frequency of wireless updates
Explanation - Adequate heat dissipation prevents sweating and skin irritation, improving long‑term wear comfort.
Correct answer is: Thermal conductivity of the liner material
Q.93 What is the purpose of a "baseline" recording in an EEG study for BCI training?
To calibrate the device’s battery level
To capture the subject’s resting brain activity for later comparison
To measure the weight of the EEG cap
To test the wireless connection speed
Explanation - Baseline data provide a reference to detect task‑related changes in EEG patterns during BCI training.
Correct answer is: To capture the subject’s resting brain activity for later comparison
Q.94 Which of the following best describes the term "bi‑directional" neural interface?
An interface that can both record neural activity and deliver stimulation
An interface that only records neural signals
An interface that transmits data only in one direction
An interface that uses two separate wires
Explanation - Bi‑directional devices enable closed‑loop operation by sensing and modulating neural circuits.
Correct answer is: An interface that can both record neural activity and deliver stimulation
Q.95 In the context of prosthetic hand control, what is meant by the term "synergistic control"?
Controlling each finger independently with separate EMG channels
Using a single signal to drive coordinated movement of multiple joints
Providing visual feedback of hand position
Adjusting the prosthetic temperature based on ambient conditions
Explanation - Synergistic control simplifies command strategies by mapping combined muscle activity to natural movement patterns.
Correct answer is: Using a single signal to drive coordinated movement of multiple joints
Q.96 Which of the following technologies is commonly used to provide "force feedback" in a robotic exoskeleton for gait training?
Accelerometers
Force‑sensing resistors (FSRs)
LED indicators
Microphones
Explanation - FSRs detect pressure changes at contact points, enabling the exoskeleton to adjust assistance based on user load.
Correct answer is: Force‑sensing resistors (FSRs)
Q.97 Which of the following best explains why "high‑density" EMG arrays can improve prosthetic control?
They reduce the cost of the prosthesis
They capture spatially detailed muscle activity patterns
They eliminate the need for power supplies
They simplify signal processing algorithms
Explanation - More electrodes provide finer mapping of muscle activation, enabling richer control signals for multiple degrees of freedom.
Correct answer is: They capture spatially detailed muscle activity patterns
Q.98 In a visual sensory substitution system that uses a camera and a tactile array, what is the main role of the "encoding algorithm"?
To convert visual pixel intensity into tactile vibration patterns
To compress audio signals for transmission
To increase the resolution of the camera sensor
To provide power management for the device
Explanation - The encoding algorithm maps visual information onto the tactile actuator array, allowing the user to perceive shapes via touch.
Correct answer is: To convert visual pixel intensity into tactile vibration patterns
Q.99 Which of the following is a key challenge when using invasive intracortical electrodes for long‑term BCI applications?
Excessive data bandwidth
Signal attenuation due to skull thickness
Glial scar formation around the electrode
Lack of sufficient power sources
Explanation - The immune response can encapsulate the electrode, degrading signal quality over time.
Correct answer is: Glial scar formation around the electrode
Q.100 What does the "signal‑to‑noise ratio (SNR)" represent in neural recordings?
The ratio of battery voltage to current draw
The proportion of useful neural activity relative to background noise
The speed at which data is transmitted wirelessly
The number of electrodes used
Explanation - Higher SNR indicates clearer recordings, essential for reliable decoding in rehabilitation devices.
Correct answer is: The proportion of useful neural activity relative to background noise
Q.101 Which of the following is a typical use of "functional magnetic resonance imaging (fMRI)" in sensory rehabilitation research?
Measuring real‑time neural activity during movement
Assessing changes in brain activation patterns after therapy
Providing direct electrical stimulation to the cortex
Monitoring skin temperature
Explanation - fMRI can visualize cortical re‑organization resulting from rehabilitation interventions.
Correct answer is: Assessing changes in brain activation patterns after therapy
Q.102 Which of the following is a common metric for evaluating the responsiveness of a tactile feedback system?
Latency (ms)
Battery capacity (mAh)
Wi‑Fi signal strength (dBm)
Screen resolution (pixels)
Explanation - Low latency ensures that tactile feedback is delivered promptly, critical for closed‑loop control.
Correct answer is: Latency (ms)
Q.103 In the design of a neural interface for upper‑limb prostheses, why is "impedance matching" important?
To ensure the device can be powered by a standard USB port
To maximize signal transfer between the electrode and amplifier
To reduce the weight of the prosthesis
To increase the visual appeal of the device
Explanation - Proper impedance matching minimizes signal loss and noise, improving recording fidelity.
Correct answer is: To maximize signal transfer between the electrode and amplifier
Q.104 Which of the following best describes the concept of "neural decoding"?
Encoding sensory information into visual signals
Translating recorded neural activity into intended actions or commands
Measuring blood flow in the brain
Generating synthetic neurons
Explanation - Decoding algorithms interpret patterns of neural firing to infer user intent for device control.
Correct answer is: Translating recorded neural activity into intended actions or commands
Q.105 What is a typical advantage of using "soft, stretchable" electronics for skin‑mounted EEG sensors?
Higher sampling rates
Improved mechanical compliance with skin movements
Reduced need for power
Simplified data encryption
Explanation - Stretchable electronics conform to the skin, reducing motion artifacts and enhancing comfort.
Correct answer is: Improved mechanical compliance with skin movements
Q.106 Which of the following is a primary use of "event‑related potentials (ERPs)" in neurorehabilitation?
To measure muscular strength
To assess cognitive processing and attention during tasks
To monitor heart rate variability
To control prosthetic battery charging
Explanation - ERPs, such as the P300, provide insight into how the brain processes stimuli, useful for training and assessment.
Correct answer is: To assess cognitive processing and attention during tasks
Q.107 In a sensory neuroprosthetic system, which component typically translates sensor data into electrical stimulation patterns?
Power supply unit
Signal encoder/controller
Wireless antenna
Battery charger
Explanation - The encoder maps sensed parameters (e.g., force) to appropriate stimulation waveforms for neural feedback.
Correct answer is: Signal encoder/controller
Q.108 Which of the following is a major limitation of using "vibrotactile" feedback alone for conveying complex sensory information?
High power consumption
Limited spatial resolution of tactile perception
Inability to produce any sensation
Requires surgical implantation
Explanation - Human skin can only distinguish a limited number of vibration sites, restricting the amount of information that can be conveyed.
Correct answer is: Limited spatial resolution of tactile perception
Q.109 Which of the following best defines "closed‑loop" functional electrical stimulation (FES) for gait rehabilitation?
Stimulating muscles at a fixed frequency regardless of movement
Adjusting stimulation parameters based on real‑time gait phase detection
Providing continuous stimulation without sensor feedback
Using FES only during sleep
Explanation - Closed‑loop FES uses sensors (e.g., IMUs) to synchronize stimulation with the user's gait cycle for natural walking patterns.
Correct answer is: Adjusting stimulation parameters based on real‑time gait phase detection
Q.110 Which of the following is an example of a "non‑invasive" neural interface?
Intracortical microelectrode array
Cochlear implant
Surface EEG cap
Deep brain stimulation lead
Explanation - EEG caps record brain activity from the scalp without penetrating tissue.
Correct answer is: Surface EEG cap
Q.111 In sensory rehabilitation, the "threshold of detection" refers to:
The minimum stimulus intensity that elicits a perceptible sensation
The maximum voltage a device can output
The fastest possible data transmission rate
The highest frequency a motor can achieve
Explanation - Detection threshold determines the lowest level of stimulation a user can reliably feel.
Correct answer is: The minimum stimulus intensity that elicits a perceptible sensation
Q.112 Which of the following signal processing steps is essential before applying machine‑learning classifiers to EMG data?
Fourier transform to convert to frequency domain
Normalization and feature extraction (e.g., RMS, zero‑crossings)
Increasing the electrode size
Adding random noise to the signal
Explanation - Standardizing the data and extracting discriminative features improve classifier performance.
Correct answer is: Normalization and feature extraction (e.g., RMS, zero‑crossings)
Q.113 Which of the following is a typical benefit of using "virtual reality" (VR) environments in sensory rehabilitation therapy?
Increasing the cost of therapy
Providing immersive, controllable sensory experiences for training
Eliminating the need for any physical devices
Reducing the need for patient engagement
Explanation - VR can simulate realistic scenarios, enabling repetitive, task‑specific practice with adjustable difficulty.
Correct answer is: Providing immersive, controllable sensory experiences for training
Q.114 In a prosthetic limb that uses "patterned electrical stimulation" for sensory feedback, what does the term "encoding scheme" refer to?
The method for converting sensor data into stimulation timing and amplitude patterns
The battery charging protocol
The wireless communication frequency
The mechanical design of the prosthetic socket
Explanation - The encoding scheme determines how physical variables (e.g., pressure) are mapped onto stimulation parameters the user can interpret.
Correct answer is: The method for converting sensor data into stimulation timing and amplitude patterns
Q.115 Which of the following best describes the "somatotopic" organization of the primary somatosensory cortex?
Neurons are randomly arranged
Adjacent body parts are represented in adjacent cortical areas
All body parts are represented in a single, uniform area
Only the hands are represented
Explanation - The somatotopic map (homunculus) preserves the spatial relationship of body regions in cortical layout.
Correct answer is: Adjacent body parts are represented in adjacent cortical areas
Q.116 Which of the following technologies is commonly used to provide "haptic" feedback for virtual reality training in stroke rehabilitation?
Force‑feedback joysticks
LED light strips
Audio headphones
Temperature sensors
Explanation - Force‑feedback devices can simulate resistance and tactile cues, enhancing motor learning in VR environments.
Correct answer is: Force‑feedback joysticks
Q.117 What is the primary purpose of a "ground" electrode in surface EMG recordings?
To increase the signal amplitude
To provide a reference point and reduce common‑mode noise
To stimulate the muscle
To measure skin temperature
Explanation - A ground electrode helps cancel out electrical interference, improving signal quality.
Correct answer is: To provide a reference point and reduce common‑mode noise
Q.118 Which of the following is a common method for assessing the usability of a new sensory neuroprosthetic device?
Measuring the device’s weight
Conducting the System Usability Scale (SUS) questionnaire with participants
Testing the device’s Wi‑Fi range
Counting the number of LEDs on the device
Explanation - SUS provides a standardized assessment of user satisfaction, ease of use, and overall acceptability.
Correct answer is: Conducting the System Usability Scale (SUS) questionnaire with participants
Q.119 Which of the following best explains why "high‑impedance" electrodes are generally avoided for long‑term EMG recordings?
They consume more power
They increase the risk of skin irritation
They produce higher noise levels, reducing signal quality
They are too large for practical use
Explanation - High impedance leads to greater thermal noise and poorer signal‑to‑noise ratio, compromising recording stability.
Correct answer is: They produce higher noise levels, reducing signal quality
Q.120 Which of the following is a typical advantage of using "optical fiber" based sensors for measuring strain in rehabilitation devices?
Immunity to electromagnetic interference
Low cost compared to metal strain gauges
Ability to directly stimulate nerves
Built‑in battery storage
Explanation - Optical fibers are not affected by electromagnetic fields, making them ideal for environments with electrical stimulation.
Correct answer is: Immunity to electromagnetic interference
Q.121 In the context of sensory feedback, what does "spatial resolution" refer to?
The speed at which a signal is transmitted
The smallest distance between two distinguishable tactile stimuli
The power consumption of the device
The number of colors displayed on a screen
Explanation - Higher spatial resolution allows the user to perceive finer details through touch.
Correct answer is: The smallest distance between two distinguishable tactile stimuli
Q.122 Which of the following best describes the principle behind "functional electrical stimulation" (FES) for restoring hand grasp?
Delivering electrical currents to muscles to elicit contraction and produce functional movement
Applying heat to the forearm to increase blood flow
Using magnets to align muscle fibers
Providing auditory cues to guide movement
Explanation - FES activates paralyzed muscles, enabling tasks such as grasping when voluntary control is lost.
Correct answer is: Delivering electrical currents to muscles to elicit contraction and produce functional movement
Q.123 Which of the following is a primary reason for incorporating "machine‑learning" classifiers in BCI‑driven prosthetic control?
To reduce the size of the prosthetic hand
To improve the accuracy and adaptability of interpreting neural signals
To eliminate the need for any sensors
To increase the prosthetic’s weight
Explanation - Machine‑learning algorithms can handle variability in neural data, enhancing reliable prosthetic command generation.
Correct answer is: To improve the accuracy and adaptability of interpreting neural signals
Q.124 Which of the following is an example of a "peripheral" neural interface?
Cortical EEG cap
Deep brain stimulation electrode
Peripheral nerve cuff electrode
Functional MRI scanner
Explanation - Cuff electrodes wrap around peripheral nerves, providing a means to record or stimulate outside the central nervous system.
Correct answer is: Peripheral nerve cuff electrode
Q.125 Which of the following best defines "neuroprosthetic" embodiment?
The visual appearance of the prosthetic device
The user's sense that the prosthetic is part of their own body
The battery life of the prosthetic
The mechanical strength of the prosthetic
Explanation - Embodiment reflects the integration of artificial limb into the body schema, often enhanced by sensory feedback.
Correct answer is: The user's sense that the prosthetic is part of their own body
Q.126 What is the main function of a "filter" in a neural signal acquisition system?
To increase the voltage of the signal
To remove unwanted frequency components (noise) from the recorded signal
To store the data for later analysis
To charge the device’s battery
Explanation - Filters improve signal quality by eliminating frequencies outside the range of interest.
Correct answer is: To remove unwanted frequency components (noise) from the recorded signal
Q.127 In a prosthetic hand with "force‑feedback" via vibrotactile actuators, increasing the vibration frequency typically conveys:
Higher grip force
Lower battery level
Faster movement speed
Cooler temperature
Explanation - Higher frequency vibrations can be mapped to stronger grip forces, providing an intuitive cue for the user.
Correct answer is: Higher grip force
Q.128 Which of the following is a common method for calibrating an EMG‑controlled prosthetic device?
Recording EMG signals while the user performs predefined muscle contractions
Measuring the weight of the prosthetic limb
Testing the Wi‑Fi signal strength
Recording heart rate variability
Explanation - Calibration involves mapping specific EMG patterns to desired prosthetic movements.
Correct answer is: Recording EMG signals while the user performs predefined muscle contractions