Behavioural Processes 44 (1998) 19–43
Linear responses
Larry Hawkes, Charles P. Shimp *
Psychology Department, Uni6ersity of Utah,
390
S.
1530
E. Rm
502
, Salt Lake City, UT
84112
-
0251
, USA
Received 27 August 1997; received in revised form 5 May 1998; accepted 15 May 1998
Abstract
Four experiments established complex choice responses a few seconds in duration. A response was reinforced if it
sufficiently approximated a ‘target’ response. The two target responses in each experiment were linear in the sense that
they involved either constant rates, or constant rates of change, in component key pecking by pigeons. For example,
in Experiment 4, one target response consisted of the linearly increasing pattern of 0, 1, 2, and 3 pecks per s in four
successive seconds, and the other response consisted of 3, 2, 1, and 0 pecks per s. Contingencies were ‘tolerant’ in the
sense that they permitted variability across different reinforced exemplars of a response. Responses approximated
target responses, at least crudely in terms of overall cumulative records, and sometimes even quantitatively in terms
of within-trial, local sequential organization. In this sense, the ‘contents’ of at least some choice responses, like their
‘envelopes’, can be shaped. That is, patterning within their boundaries, in addition to their relative and absolute
durations, can be shaped. Some responses may have emerged from variability inherent in component pecking
occurring at a constant probability, thereby demonstrating a few cases where the relation between molecular and
molar analyses fully legitimizes a molar analysis. © 1998 Published by Elsevier Science B.V. All rights reserved.
Keywords
:
Molar and molecular analyses
1. Introduction
Complex behavior of nonhuman animals chal-
lenges both method and theory because of
difficulties in establishing and in conceptualizing
sequential organization (Lashley, 1951; Anger,
1956; Jenkins, 1970; Shimp, 1976a,b; Hulse, 1978;
Marr, 1979; Thompson and Zeiler, 1986; Iversen,
1991; Terrace, 1991, 1993; Shimp et al., 1994;
Terrace et al., 1996). That is, sequential organiza-
tion poses two interrelated challenges. First, to
determine which arbitrary sequential patterns can
or cannot be established by the direct shaping
effects of reinforcement requires complex empiri-
cal methods. Second, in addition to this methodo-
logical challenge, there is the conceptual challenge
to articulate the link between simple and complex
* Corresponding author. Tel.: + 1 801 5818483; fax: +1
801 5815841; e-mail: shimp@psych.utah.edu
0376-6357/98/$ - see front matter © 1998 Published by Elsevier Science B.V. All rights reserved.
PII
S0376-6357(98)00029-1