Newton,Goethe and the Alleged Underdetermination of Ray Optics

Did Goethe devise an empirically viable theory of classical ray optics? Or can we at least make use of his ideas to propose one? And if so, does this confront us with an intriguing case of theory underdetermination? In this paper, which is mainly a comment on the recent work of Olaf Müller, I shall address these three questions and argue for ‘no, yes, no’. This is in contrast to Müller, who has recently launched a vivid defense of Goethe-style ray optics (Müller in “Mehr Licht. Goethe mit Newton im Streit um die Farben.” Fischer, Frankfurt a.M., 2015a; Z Philos Forsch 69(4):569–573, 2015b; Z Philos Forsch 69(4):588–598, 2015c; Br J Hist Philos 24(2):322–346, 2016). Müller aims to give an almost positive answer to all three questions: ‘perhaps, yes, yes’. My overall line of argument will be that the rather restricted regime of classical geometrical optics of spectral colors (or ray optics, for short) allows at best for a weak form of transient theory underdetermination that, in turn and more straightforwardly, also allows for a structuralist reading in terms of two structurally equivalent formulations of one and the same theory. However, extending any of the rivaling models of ray optics other than Newton’s beyond the mentioned regime and embedding them into physics in total—especially in view of thermodynamics—leads to a contradiction. Hence, Newton’s theory is confirmed as the only consistent theoretical interpretation of ray optics.     

Dissociation of acquisition and expression of fear conditioned responses under working memory load

Previously, it has been suggested that high working memory load (WML) prevents associative learning and, thus, conditioned responses (CRs) during differential-delay fear conditioning. However, previous studies did not distinguish between the effects of WML on the acquisition versus the expression of the CRs. In the present study, we reinvestigated this issue by manipulating WML during either acquisition or postconditioning and showed that the absence of a differential CR under high WML does not indicate the absence of the acquisition of this CR. Thus, a significant CR was observed during a task-free postconditioning phase, and there was no CR during the preceding acquisition phase with high WML. Conversely, a normally acquired CR was impaired by high WML during the postconditioning phase. The results suggest that high WML affects the expression of the CR. If they are not experimentally separated, the effects of WML on the acquisition and expression of the CR may occur together, and the findings may be erroneously interpreted as indicating a lack of associative learning.     

The structure of semantic person memory: evidence from semantic priming in person recognition

This paper reviews research on the structure of semantic person memory as examined with semantic priming. In this experimental paradigm, a familiarity decision on a target face or written name is usually faster when it is preceded by a related as compared to an unrelated prime. This effect has been shown to be relatively short lived and susceptible to interfering items. Moreover, semantic priming can cross stimulus domains, such that a written name can prime a target face and vice versa. However, it remains controversial whether representations of people are stored in associative networks based on co-occurrence, or in more abstract semantic categories. In line with prominent cognitive models of face recognition, which explain semantic priming by shared semantic information between prime and target, recent research demonstrated that priming could be obtained from purely categorically related, non-associated prime/target pairs. Although strategic processes, such as expectancy and retrospective matching likely contribute, there is also evidence for a non-strategic contribution to priming, presumably related to spreading activation. Finally, a semantic priming effect has been demonstrated in the N400 event-related potential (ERP) component, which may reflect facilitated access to semantic information. It is concluded that categorical relatedness is one organizing principle of semantic person memory.     

Ageing faces in ageing minds: A review on the own-age bias in face recognition

Similar to the well-established own-race bias, participants are more accurate at remembering own- relative to other-age faces. An own-age bias (OAB) in face memory was demonstrated in participants older than approximately 5 years. Crucially, the OAB is modulated by contact—participants with substantial contact with other-age persons show either reduced or absent OAB effects. In line with a perceptual expertise account of the phenomenon, holistic processing of other-age faces is less efficient when tested with young adult versus child faces, and differential holistic processing may therefore reflect one mechanism contributing to the OAB. A possible additional contribution of sociocognitive factors to the OAB remains largely untested. Importantly, event-related brain potential studies suggest that the own-race and own-age biases are based on at least partly different mechanisms. Theoretical explanations for different group-based biases in face memory will need to consider these findings.     

Phonological abstraction without phonemes in speech perception

Recent evidence shows that listeners use abstract prelexical units in speech perception. Using the phenomenon of lexical retuning in speech processing, we ask whether those units are necessarily phonemic. Dutch listeners were exposed to a Dutch speaker producing ambiguous phones between the Dutch syllable-final allophones approximant [r] and dark [l]. These ambiguous phones replaced either final /r/ or final /l/ in words in a lexical-decision task. This differential exposure affected perception of ambiguous stimuli on the same allophone continuum in a subsequent phonetic-categorization test: Listeners exposed to ambiguous phones in /r/-final words were more likely to perceive test stimuli as /r/ than listeners with exposure in /l/-final words. This effect was not found for test stimuli on continua using other allophones of /r/ and /l/. These results confirm that listeners use phonological abstraction in speech perception. They also show that context-sensitive allophones can play a role in this process, and hence that context-insensitive phonemes are not necessary. We suggest there may be no one unit of perception.     

The fragile nature of the speech-perception deficit in dyslexia: natural vs synthetic speech

A number of studies reported that developmental dyslexics are impaired in speech perception, especially for speech signals consisting of rapid auditory transitions. These studies mostly made use of a categorical-perception task with synthetic-speech samples. In this study, we show that deficits in the perception of synthetic speech do not generalise to the perception of more naturally sounding speech, even if the same experimental paradigm is used. This contrasts with the assumption that dyslexics are impaired in the perception of rapid auditory transitions.     

Das Problem der Chronometerauswahl

On Choice of Time Metric. What criteria ought to be satisfied by those observable processes which, accompanied by a function assigning values to intervals of that processes, serve as the standard for measurement of time? In how far do the criteria which can reasonably be established admit of an unambigous definition of time metric? That are the questions to which I have addressed myself in the paper. Peter Janich has aimed at solving the problem with careful avoidance of any reference to physical theory. Although this paper owes a great deal to his ‘Protophysik der Zeit’, reasons will be ad-vanced that it is in principle impossible to give a foundation of time metric without any reference to physical theory. It follows that taking results of physical theory into account is unavoidable as far as a definite decision concerning the choice of time metric is aspired. At first sight reference to law-like assertions on the duration of temporal intervals appears to be paradoxical for it means to take something which originally ought to be submitted to experimental test as the standard for measurement. Poincaré is fairly conscious of this problem, yet explicitly acknowledges that there is a mutual relationship between definition of time metric and physical theory. It will be shown that this kind of mutual relationship which even might be termed as circular does not void physical theory of empirical content. Thus in the final part I am concerned to free the position which recommends reference to physical theory from its paradoxical image in order to advance a conventionalist account as a sceptical, but nevertheless fully satisfying solution.     

On the causes of compensation for coarticulation: evidence for phonological mediation

This study examined whether compensation for coarticulation in fricative-vowel syllables is phonologically mediated or a consequence of auditory processes. Smits (2001a) had shown that compensation occurs for anticipatory lip rounding in a fricative caused by a following rounded vowel in Dutch. In a first experiment, the possibility that compensation is due to general auditory processing was investigated using nonspeech sounds. These did not cause context effects akin to compensation for coarticulation, although nonspeech sounds influenced speech sound identification in an integrative fashion. In a second experiment, a possible phonological basis for compensation for coarticulation was assessed by using audiovisual speech. Visual displays, which induced the perception of a rounded vowel, also influenced compensation for anticipatory lip rounding in the fricative. These results indicate that compensation for anticipatory lip rounding in fricative-vowel syllables is phonologically mediated. This result is discussed in the light of other compensation-for-coarticulation findings and general theories of speech perception.     

The role of perceptual integration in the recognition of assimilated word forms

We investigated how spoken words are recognized when they have been altered by phonological assimilation. Previous research has shown that there is a process of perceptual compensation for phonological assimilations. Three recently formulated proposals regarding the mechanisms for compensation for assimilation make different predictions with regard to the level at which compensation is supposed to occur as well as regarding the role of specific language experience. In the present study, Hungarian words and nonwords, in which a viable and an unviable liquid assimilation was applied, were presented to Hungarian and Dutch listeners in an identification task and a discrimination task. Results indicate that viably changed forms are difficult to distinguish from canonical forms independent of experience with the assimilation rule applied in the utterances. This reveals that auditory processing contributes to perceptual compensation for assimilation, while language experience has only a minor role to play when identification is required.