[RePro] Measures f-I-curves for a superposition of two sine waves. More...

#include <isoresponse.h>

Inheritance diagram for IsoResponse:

Collaboration diagram for IsoResponse:

Classes
struct	FIData
struct	IsoData
Public Member Functions
	IsoResponse (void)
	~IsoResponse (void)
virtual int	main (void)
void	saveSpikes (const Options &header)
void	saveRates (const Options &header)
void	plot (void)
void	analyze (const OutData &signal)
Protected Member Functions
void	setFRBounds (double max)
void	setIBounds (void)
void	createSignal (OutData &signal, double a1, double a2)
int	findIsoFreq (void)
void	findScaling (void)
void	plotIsoSets (void)
Protected Attributes
double	Flow
double	Fup
vector< double >	FIso
double	IntCorrection
double	Scaling
double	pi
double	A0
int	UseBestFrequency
double	BestFreq
double	DistBestFrequency
double	DistFrequencies
double	Frequency1
double	Frequency2
double	MinIntensity
double	MaxIntensity
double	FinalResolution
double	EstimResolution
RangeLoop::Sequence	IntShuffle
bool	ShortStim
double	Duration
double	Pause
double	OnWidth
double	SSWidth
bool	FITest
int	Repeats
int	EstRepeats
int	Side
double	IntensityUp
bool	Switch_high
double	FRhigh_per
double	FRhigh_fix
bool	Switch_low
double	FRlow_per
double	FRlow_fix
double	MinFR
int	IrsNumber
int	IrsPoints
int	State
MultiPlot	P
RangeLoop	IntensityRange
double	Intensity
RangeLoop	AmplitudeRelation
double	AmplFraction
OutData	Signal
double	AmplRatio
int	MaxRatePos
double	MaxRate
vector< FIData >	Results
vector< IsoData >	IsoResults

Detailed Description

[RePro] Measures f-I-curves for a superposition of two sine waves.

Author:: Alexander Wolf

IsoResponse extrapolates Iso-Response-Sets (IRSs) for two sine amplitudes A1 and A2, i.e. for several combinations of A1 and A2 f-I-curves are recorded and the intensities determined at which the firing rate of the cell reaches predefined values. The stimulus looks like this: s(t)=A1*sin(2pi*f1*t)+A2*sin(2pi*f2*t).

The frequencies can either be set manually (use_best_freq=0), or set at a fixed distance (dist_best_freq) from either side the best frequency (use_best_freq=1), or set at a fixed distance from each (dist_freq) other so that the pure tone stimuli have the same sensitivity according to the tuning curve (use_best_freq=2). !The last option is to be prefered; however, it does not work in all cases!

The stimulus length is defined by 'duration', the time in between stimuli by 'pause'. For each stimuli presentation we record the onset response in the time intervall 'onwidth', and the steady state response after time 'sswidth' has passed, except when 'short_stim' is true - then only the onset is recorded.

The intensity of the signal ranges from 'intmin' to 'intmax'. To find the relevant range in which the f-I-curve rises, the interval is tested with a resolution of 'estres' and each data point is measure 'estrepeats' times. When the relevant range is determined, the resolution is decreased to 'intres' and each point is repeated 'repeats' times. The order in which the intensities is measured is determined with the switch 'inshuffle' (see RangeLoop).

'setFRbounds' determines the limits of the firing rate in between which the f-I-curve is to be measured. If 'switch_high' ('switch_low') is true, the upper (lower) bound is set to 'fix_high' ('fix_low'). Otherwise, the bounds are set to the experimentally determined maximum firing rate fmax minus 'per_high' ('per_low') percent. 'setIBounds' determines then the intensity range by finding the intensities at which the upper and lower bound for the firing rate are reached.

The fraction of the amplitudes ('AmplFraction') determines the shape of the signal. In order to scan the amplitude space equidistantly, we use the tangent of 'AmplFraction' and a scaling factor 'Scaling'. 'Scaling' is estimated from the f-I-curves of the pure tones ('findScaling') to equalize the difference in sensitivity of the two stimulus frequencies. The relative amplitudes of the mixed stimuli are determined by 'AmplRatio'.

The IRSs are determined in 'plotIsoSets' for 'isonumber' firing rates 'FIso'. The extrapolation is only linear using two points. It is therefore strongly recommended to analyze the data offline.

Options

The following options are supported (brief description of each option with default values and data type):

Stimulus
Frequencies
use_best_freq=absolute: Frequency reference (string)
dist_best_freq=1kHz*3/pi: Distance of f1 and f2 from best Frequency (for 'best') (number)
dist_freq=2kHz*3/pi: Distance between f1 and f2 (for 'isothresh') (number)
f1=4kHz: 1st Frequency (number)
f2=10kHz*3/pi: 2nd Frequency (number)
Intensities
intmin=30dB SPL: Minimum stimulus intensity (number)
intmax=100dB SPL: Maximum stimulus intensity (number)
intres=1dB SPL: Final intensity resolution (number)
estres=5dB SPL: Resolution for estimation of FR-range (number)
intshuffle=Up: Order of intensities (string)
Stimulus Structure
short_stim=true: Measure Onset Response only (boolean)
duration=200ms: Stimulus duration (number)
pause=300ms: Pause between stimuli (number)
onwidth=10ms: Window length for onset firing rate (number)
sswidth=100ms: Window length for steady-state firing rate (number)
Analysis
repeats=12: Number of repeats for each stimulus (integer)
estrepeats=3: Repeats for stimulus while estimating f-I-curve (integer)
side=best: Speaker (string)
Analysis Bounds
intup=5dB SPL: Increases upper intensity bound by: (number)
switch_high=false: Higher bound FR fixed (boolean)
per_high=5%: Percentage of max FR (number)
fix_high=500Hz: Absolute value for bound of upper FR (number)
switch_low=false: Lower bound FR fixed (boolean)
per_low=50%: Percentage of max FR (number)
fix_low=150Hz: Absolute value for lower bound of FR (number)
minfr=30Hz: Minimum firing rater response (number)
Iso-Response-Sets
isonumber=5: Number of Iso-Response-Sets evaluated (integer)
isopoints=33: Number of data points on each IRS (integer)

Keyboard shortcuts:

Space: Pressing space twice aborts IsoResponse after finishing up measuring the curent f-I curve.

Files:

isoresponsespikes.dat: The spike trains...
isoresponserates.dat: Continuous recording of measured f-I-curves. Before each f-I-curve the header data is recorded. The 'run' number marks the experiment. In the table you find the intensity, the true intensity, first and second stimulus amplitude, onset firing rate and standard deviation, the steady state firing rate and standard deviation, the mean firing rate and standard deviation, and the number of repetitions:

I(dB SPL) I_t(dB SPL) A1(mPa) A2(mPa) f_on(Hz) sd(Hz) f_s(Hz) sd(Hz) f_m(Hz) sd(Hz) trials