Table 1.

Demographic information for the 7 bilateral CI subjects included in the present study

Subject		Loss of Hearing			CI Internal Device		CI External Device		CI Activated		Electrodes Tested		Other Measures
Code	Age, yr	Left	Right	Etiology	Left	Right	Left	Right	Left	Right	Apical	Basal	Best ITD JND*, μs	Speech in quiet/noise†
CI1	73	∼1995	∼1995	Unknown	CI24R(CS)	CI24RE(CA)	Freedom	CP810	2/2003	3/2008	L18-R18	L4-R6	58	95%/57%
CI2	62	2002	2002	Hereditary	CI24RE(CA)	CI24RE(CA)	Freedom	Freedom	5/2007	11/2005	L18-R19	L10-R13	23	N/A
CI3	55	∼1980	∼1980	Unknown	CI24RE(CA)	CI24RE(CA)	Freedom	Freedom	9/2008	6/2009	L18-R18	L4-R6	141	88%/60%
CI4	67	2010	2010	Radiation	Freedom	CI512	CP810	CP810	4/2012	4/2011	L20-R21	L8-R10	136	N/A
CI5	64	∼1960	∼1960	Hereditary	CI24RE(CA)	CI24R(CA)	CP810	CP810	9/2005	11/2002‡	L18-R19	L4-R4	193	92%/63%
CI6	65	∼1961	∼1961	Unknown	CI512	CI512	CP810	CP810	12/2009	12/2009	L20-R16	L4-R6	160	80%/47%
CI7	61	∼1970	∼1970	Nerve damage	CI512	CI24RE(CA)	CP810	CP810	6/2010	8/2011§	L20-R20	L4-R5	121	98%/77%

CI, cochlear implant.

^*The given interaural time difference (ITD) JNDs were determined previously with 100 pulse/s direct stimulation (see text) of pitch-matched and loudness-balanced electrode pairs (not necessarily the same electrode pairs tested in the present study).

^†The given speech recognition scores, collected in the free field with subjects wearing their clinical processors, represent % correct word recognition for closed sets of 50 single words presented at 50 dB SPL from a loudspeaker at 0° azimuth, either in quiet or with simultaneous 50 dB SPL broadband noise presented from loudspeakers to the left and right of the subject (±90°). Data were unavailable (N/A) for subjects CI2 and CI4.

^‡Subject CI5 was initially implanted in the right ear in 11/2002 but was reimplanted with the listed devices in 2/2005.

^§Subject CI7 was initially implanted in the right ear in 8/2011 but was reimplanted with the listed devices in 3/2012.