John Morton - Academia.edu (original) (raw)

Papers by John Morton

Cognitive Neuropsychology, 2005

Behavioral and Brain Sciences, 2004

Now that consciousness is thoroughly out of the way, we can focus more precisely on the kinds of ... more Now that consciousness is thoroughly out of the way, we can focus more precisely on the kinds of things that can happen underneath. A contrast can be made between dissociation and repression. Dissociation is where a memory record or set of autobiographical memory records cannot be retrieved; repression is where there is retrieval of a record but, because of the current task specification, the contents of the record, though entering into current processing, are not allowed into consciousness. I look at hypnotic amnesia and dissociative identity disorder in relation to this contrast.

Behavioral and Brain Sciences, 1995

We make three suggestions with regard to Mealey's work. First, her lack of a cognitive analys... more We make three suggestions with regard to Mealey's work. First, her lack of a cognitive analysis of the sociopath results in underspecified mappings between sociobiology and behavior. Second, the developmental literature indicates that Mealey's implicit assumption, that moral socialisation is achieved through punishment, is invalid. Third, we advance the use of causal modelling to map the developmental relationships between biology, cognition, and behaviour.

The Journal of Neuroscience, 2006

The ventromedial prefrontal cortex (vmPFC) and dorsal anterior cingulate cortices (ACd) are consi... more The ventromedial prefrontal cortex (vmPFC) and dorsal anterior cingulate cortices (ACd) are considered important for reward-based decision making. However, work distinguishing their individual functional contributions has only begun. One aspect of decision making that has received little attention is that making the right choice often translates to making the better choice. Thus, response choice often occurs in situations where both options are desirable (e.g., choosing between mousse au chocolat or crème caramel cheesecake from a menu) or, alternatively, in situations where both options are undesirable. Moreover, response choice is easier when the reinforcements associated with the objects are far apart, rather than close together, in value. We used functional magnetic resonance imaging to delineate the functional roles of the vmPFC and ACd by investigating these two aspects of decision making: (1) decision form (i.e., choosing between two objects to gain the greater reward or the ...

Personality and Individual Differences, 2006

In this study, we examined decision-making to rewarding or punishing stimuli in individuals with ... more In this study, we examined decision-making to rewarding or punishing stimuli in individuals with psychopathy (n = 21) and comparison individuals (n = 19) using the Differential Reward/Punishment Learning Task. In this task, the participant chooses between two objects associated with different levels of reward or punishment. Thus, response choice indexes not only reward/punishment sensitivity but also sensitivity to reward/punishment level according to inter-stimulus reinforcement distance. Individuals with psychopathy showed significant impairment when choosing between objects associated with differential levels of reward but also significantly greater impairment when choosing between objects associated with differential levels of punishment. However, the two groups were comparably affected by inter-stimulus reinforcement distance. The results are discussed with reference to current models of psychopathy.

NeuroImage, 2007

In this study, we examined the impact of goal-directed processing on the response to emotional pi... more In this study, we examined the impact of goal-directed processing on the response to emotional pictures and the impact of emotional pictures on goal-directed processing. Subjects (N=22) viewed neutral or emotional pictures in the presence or absence of a demanding cognitive task. Goal-directed processing disrupted the BOLD response to emotional pictures. In particular, the BOLD response within bilateral amygdala and inferior frontal gyrus decreased during concurrent task performance. Moreover, the presence of both positive and negative distractors disrupted task performance, with reaction times increasing for emotional relative to neutral distractors. Moreover, in line with the suggestion of the importance of lateral frontal regions in emotional regulation [Ochsner, K.

Biological Psychology, 2006

Previous work has indicated dysfunctional affect-language interactions in individuals with psycho... more Previous work has indicated dysfunctional affect-language interactions in individuals with psychopathy through use of the lexical decision task. However, it has been uncertain as to whether these deficits actually reflect impaired affect-language interactions or a more fundamental deficit in general semantic processing. In this study, we examined affective priming and semantic priming (dependent measures were reaction times and error rates) in individuals with psychopathy and comparison individuals, classified according to the psychopathy checklist revised (PCL-R) [Hare, R.D., 1991. The Hare Psychopathy Checklist-Revised. Multi-Health Systems, Toronto, Ont.]. Individuals with psychopathy showed significantly less affective priming relative to comparison individuals. In contrast, the two groups showed comparable levels of semantic priming. The results are discussed with reference to current models of psychopathy.

Journal of Experimental Psychology, 1971

A number of experiments are described which use the stimulus suffix effect (SSE) to determine the... more A number of experiments are described which use the stimulus suffix effect (SSE) to determine the properties of the precategorical acoustic store (PAS) described by R. G. Crowder and J. Morton in 1969. The SSE is a selective impairment of recall of the final items in a serial recall list engendered by a redundant acoustic event following acoustic presentation. First, it is established that such intrinsic properties of the suffix as its meaning, frequency of occurrence, and emotionality have no bearing on the size of the suffix effect. This confirms the precategorical nature of the store. Second, it is shown that variation in the acoustic properties of the suffix (such as its apparent spatial location, timbre, and pitch) with respect to the stimuli reduces the size of the SSE. Variations on this theme indicate that PAS is located after a mechanism of selection between acoustic channels and before the convergence of acoustic and visual analysis systems.

American Psychologist, 1991

Several disagreements with Banaji and Crowder's (1989) work on everyday memory are presented. Psy... more Several disagreements with Banaji and Crowder's (1989) work on everyday memory are presented. Psychology is no longer a young science. The progress of research in memory is being impeded not by the everyday memory movement, but by an excessively restricted theoretical base. First, the key notion of generalizability is being applied over data, rather than over mechanisms. Second, theories of memory take insufficient account of other mental functions.

Journal of Verbal Learning and Verbal Behavior, 1976

window. This was accounted for by a timesharing hypothesis, it being supposed that some limited-c... more window. This was accounted for by a timesharing hypothesis, it being supposed that some limited-capacity decision-making process is implicated at various linguistic levels, for example, phonological, lexical, surface structure, deep structure. In such a model, the difficulty of the decision at any one level would affect the speed and accuracy of decisions at another level. Since the syntax of self-embedded sentences is more complex, RTs to words in such a framework would be longer. Foss (1969) then found that the RT to a target phoneme was affected by the frequency of

Language and Speech, 1965

The use of the term ‘stress’ is reviewed, and inconsistencies are pointed out An experiment is de... more The use of the term ‘stress’ is reviewed, and inconsistencies are pointed out An experiment is described in which synthetic nonsense syllables of the forms /sisi/, /S⊃S⊃/ and /sasa/ were played to subjects who were asked to judge the position of the stress. The parameters of fundamental frequency, intensity and duration were varied systematically. The results revealed a high level of consistency between the (naive) subjects. Variations in fundamental frequency produced far greater effects than variations in either intensity or duration, a syllable being marked as stressed if it differed from the ‘context’ fundamental. A raised fundamental was more efficient than a lowered one. In general the more intense and longer syllables were more likely to be marked as stressed, the exception being when a syllable was reduced in duration by 40%, when some listeners marked it as stressed. The use and limitations of the results and method are discussed.

Early Development and Parenting, 1993

Models of Human Memory, 1970

Journal of Experimental Psychology, 1974

Sixteen 5s learned a word list and were then tested on recognition of words presented tachistosco... more Sixteen 5s learned a word list and were then tested on recognition of words presented tachistoscopically. When a test word was identical to one of the learned words, recognition was facilitated in the usual way. Pretraining with a word that was a different derivative of the same root morpheme as a test word gave significant facilitation of recognition of that test word. However, learning a word with comparable visual-acoustic similarity but no morphemic relation to a test word gave only slight, nonsignificant facilitation of recognition. It was concluded that the process of recognizing a word involves assigning it to a linguistic unit with specific semantic associations, i.e., a morpheme. Analysis of error responses suggested that, to some extent, root and suffix morphemes are recognized independently, and that suffixes themselves may be subject to frequency effects. The principles underlying the phenomena studied may be most appropriately characterized as "the morpheme-frequency effect." 1 This work was carried out at the Psychological Laboratory, University of Cambridge, while the first author was a final year undergraduate. The assistance of those who acted as Ss is gratefully acknowledged. 2 Requests for reprints should be sent to Graham

Neuropsychologia, 1977

Three experiments are reported using confrontation naming with aphasic patients. In the first exp... more Three experiments are reported using confrontation naming with aphasic patients. In the first experiment we looked at the effects of the plausibility of the context in object naming; in the second experiment we compared a plausible context with pictures of objects in isolation; in the last experiment we compared the naming of line drawings with that of real objects. In none of these cases were we able to find any effects of the experimental treatments. Such results bear on reasons given for the use of realism in therapy and have relevance for the appropriate form of the model of the underlying processes. * We thank in particular the consultants of Addenbrooke's Hospital, especially Mr. W. S. Lewin, for permission to study/test patients under their care.

Trends in Neurosciences, 1991

This article summarizes recent evidence indicating that individuals suffering from autism have a ... more This article summarizes recent evidence indicating that individuals suffering from autism have a specific problem in understanding intentions and beliefs. We propose that this problem arises because they are incapable of forming a special kind of mental representation. A single cognitive deficit defines what is common to all autistic individuals. In contrast there is a wide range of proposals for the biological origins of the disorder.

Psychological Review, 1976