The Columbus Instruments Responder-X is designed for precise quantification of the startle reflex vertical component, a key indicator in evaluating sensory and central nervous system (CNS) performance. The system presents stimuli while recording response latency and magnitude, offering detailed insights into neurological function.

Position-Independent Sensing

The Responder-X employs a single-point load cell for precise measurements of restrained or unrestrained animals, regardless of their location on the platform. This design ensures consistent and reliable data, eliminating variability caused by animal movement. The load cell’s high sensitivity and linear performance make it ideal for detecting subtle startle responses. By accurately quantifying these responses, researchers can gain deeper insights into CNS functionality. This position-independent sensing is crucial for obtaining reproducible and trustworthy data across experiments.

Adaptable Stimulus Presentation

The system is equipped with built-in acoustic stimuli, including white noise and pre-pulse capabilities, and can also be adapted for custom stimulus presentations such as electrical stimuli. Researchers have full control over the frequency, timing, and type of stimuli, allowing for versatile experimental designs. The system’s pseudo-random stimulus delivery feature helps prevent habituation, keeping test subjects responsive throughout experiments. This adaptability ensures that the Responder-X is suitable for a wide range of studies in sensory and CNS performance.

Comprehensive Data Collection

The Responder-X provides 1-millisecond temporal resolution for latency measurements, ensuring precise tracking of response times. The force of the response is measured, providing accurate, quantifiable data on the magnitude of startle reflexes. Data is stored and analyzed using user-friendly Windows-compatible software, allowing for easy acquisition, review, and reanalysis of results. This comprehensive data collection capability enhances the system’s utility in understanding complex neurological behaviors.

Computer Interface: USB 1.1

Audio Output:

• Frequency Range: 50 to 20,000Hz (Sinewave Tone & White Noise)
• Volume Control: 0 to -63 decibels, 1 decibel steps, mute (Computer Selected)

Audio Volume Calibration: User-adjustable ±3 decibels from nominal amplitude

Speakers:

• Connection Type: Neutrik 2-pole Speaker Connection
• Power: 40 watts maximum

Relays:

• Normally Open Contacts
• Specifications: 1V AC/DC drop @ 30mA, 150mW
• Functions: Prepulse, Stimulus, Startle Acquisition

Audio Amplifier:

• Volume: Up to 120 decibels (typical)
• Mute: On/Off function

Latency Measurement: 1 millisecond temporal resolution

Load Cell:

• Dimensions: 27.9 x 16.5 x 8.6 cm (11.0” x 6.5” x 3.4”)
• Rated Capacity: ±2.2 kilograms (±5.0 pounds)

Shock Output:

• Voltage: 400V peak-to-peak, 260V peak
• Current: 2.6mA peak (100K load) maximum