Phew! How rats sigh when they're relieved

If you ever hear a rat sigh, don’t worry it’s not because they’re getting impatient, rather it’s because they’re relieved, a behaviour that probably evolved as a safety signal to other rats. That’s according to Stefan Soltysik and Piotr Jelen at the Limbic System Laboratory of the Nencki Institute of Experimental Biology in Warsaw.

Over hundreds of trials, Soltysik and Jelen trained 16 rats to expect an electric shock to their tail after they heard an auditory tone, but not to expect a shock if a light came on after the tone. In this way, fear could be induced in the rats, followed by relief if they saw the light come on. All the while, the researchers monitored the rats’ breathing by recording their diaphragm muscles. Sighs are easily recognisable, the researchers explained, because they appear as a “deep ‘additional’ inhalation that starts at or around the peak of a normal respiratory cycle”.

Three hundred and eleven sighs were recorded across the course of the experiment, the vast majority of them during the ‘relief phase’ that followed a light coming on, indicating a shock would not occur. Averaged across all the rats, 7.4 times more sighs occurred during this ‘relief phase’ than during the equivalent period when the light didn’t come on – a fear phase – that occurred between the tone sounding and a shock being given.

The researchers said it’s possible “This respiratory act was recruited during evolution to signal reduced perception of danger, and/or to synchronise the emotional state of the group (collective sighs of relief?)…” They added that “the sigh could be a signal opposite to the alarm cry”.

To test this theory further they plan experiments to see if sighing is more prevalent in the company of other rats, and to test whether sighing is impaired in rats raised in social isolation.

Soltysik, S. & Jelen, P. (2005). In rats, sighs correlate with relief. Physiology and behaviour, 85, 598-602.
You have read this article with the title October 2005. You can bookmark this page URL Thanks!

Cognitive therapy on the couch

Cognitive therapy for depression could be improved by the therapist focusing more on the therapeutic process itself. That’s according to Jonathan Kanter (University of Wisconsin-Milwaukee) and colleagues who compared the effectiveness of therapy given by four expert cognitive therapists before and after they were given special training in this kind of therapy-focused technique.

"...sessions with more therapy-focused utterances were associated with better reports of perceived progress in weekly feedback from clients"

The therapists worked with four clients each before training, and six each after the training. Researchers listened to recordings of the therapists’ sessions and noted each time the therapists spoke and whether or not their utterances referred to the therapy or to their relationship with the clients (e.g. “I’ve noticed that you don’t look at me when we are discussing sensitive issues” or “What’s so important about whether I like you or not”). Some therapists claim they already discuss the therapeutic process with clients, but here the researchers confirmed the therapists focused more on the therapeutic process after the training. For example, they looked at the proportion of sessions in which more than one in five therapist utterances were focused on the therapeutic process: this was 3.7 per cent of sessions before training, compared with 21 per cent afterwards.

Crucially, sessions with more therapy-focused utterances were associated with better reports of perceived progress in weekly feedback from clients, and with a tendency for clients to report more improvement in their relationships. However, more focus on the therapeutic process was not related to actual symptomatic improvement, as measured by clients’ weekly completion of the Beck Depression Inventory.

Whereas this study grouped together all therapy-focused utterances, the researchers said future work should probe deeper, to identify what kinds of therapeutic focus are beneficial.

Kanter, J.W., Schildcrout, J.S. & Kohlenberg, R.J. (2005). In vivo processes in cognitive therapy for depression: Frequency and benefits. Psychotherapy Research, 15, 366-373.
You have read this article Mental health with the title October 2005. You can bookmark this page URL Thanks!

Exploring the physiological effects of thinking positively

Whereas countless studies have examined the effect of negative psychological states on levels of cortisol – a corticosteroid hormone that is associated with stress and ill-health – few, if any, have looked at the effect of positive psychological states on the hormone, a fact that Julian Lai (City University of Hong Kong) and colleagues see as part Western society’s disease-oriented view of health that “places disease and health on two opposite ends of a continuum and defines the two states as presence and absence of negative conditions, respectively”.

In an effort to rectify this bias, Lai’s team recruited 80 healthy adults, took saliva samples from them six times a day for two days (for measuring cortisol levels), and asked them to complete questionnaires about their optimism/pessimism and their mood over the last month and the last day.

They found that in men only, optimism was associated with lower cortisol levels after waking up, when levels of the hormone tend to peak as part of a daily cycle. The researchers said more research was needed to explain this gender difference. In men and women, they found that a generally positive mood during the last month was associated with lower cortisol levels over the whole day, even after controlling for good or bad mood on the day of testing.

The researchers said their findings “may draw increased attention to the potential impact of positive psychological dispositions or conditions on cortisol secretion and thus initiate a shift of research focus to the physiological substrates of positive states of minds…”. Future work should investigate whether the effects of positive psychological states on cortisol levels, as reported here, have actual health benefits, the researchers said.

Lai, J.C.L., Evans, P.D., Ng, S.H., Chong, A.M.L., Siu, O.T., Chan, C.L.W., Ho, S.M.Y., Ho, R.T.H., Chan, P. & Chan, C.C. (2005). Optimism, positive affectivity, and salivary cortisol. British Journal of Health Psychology, 10, 467-484.

Link to the Positive Psychology Centre
Link to special issue of The Psychologist on Positive Psychology (free access)
You have read this article Mental health with the title October 2005. You can bookmark this page URL Thanks!

Childhood trauma and schizophrenia

A series of articles in the November issue of Acta Psychiatrica Scandinavica explores the link between trauma and schizophrenia.

"Earlier trauma plays a causal role in schizophrenia, it’s argued, because it can leave people prone to finding...psychotic symptoms distressing"

One suggestion is that some people would not have developed schizophrenia if they hadn’t had an earlier traumatic experience. According to this argument, psychotic experiences (for example, hearing voices; having paranoid thoughts) are not necessarily pathological (e.g. see here), rather they only become problematic if a person finds them distressing. Earlier trauma plays a causal role in schizophrenia, it’s argued, because it can leave people prone to finding these psychotic symptoms distressing.

To test this idea, Maarten Bak (Maastricht University) and colleagues interviewed thousands of people from the general population who had never had a psychotic experience, to find out if they had been traumatised in any way as a child. Three years later, researchers interviewed the same people again to find out whether or not they had had a psychotic experience since the first interview, and secondly, to find out if they found their psychotic experience(s) distressing or just unusual.

Among the 16 people who reported having had one or more non-distressing psychotic experiences since the first interview, just one (six per cent) had been traumatised as a child (according to their statements in the first interview). In contrast, among the 21 people who reported having had one or more distressing psychotic experiences, nine (43 per cent) had been traumatised as a child. The people who said they’d been traumatised also tended to report having less control over their psychotic experience(s).

The authors said their findings suggest “exposure to early trauma, defined here as self-reported traumatic experiences in childhood, predisposes persons to suffer from more emotional distress associated with psychotic experiences and less perceived control over these experiences, compared with those without a traumatic history”.

Bak, M., Krabbendam, L., Janssen, I., de Graaf, R., Vollebergh, W. & van Os, J. (2005). Early trauma may increase the risk for psychotic experiences by impacting on emotional response and perception of control. Acta Psychiatrica Scandinavica, 112, 360-366.

Link to related essay in the Guardian
You have read this article Developmental / Mental health with the title October 2005. You can bookmark this page URL Thanks!

How we infer other people's expectations

A growing body of evidence suggests that we understand other people’s actions and intentions by simulating their movements in the motor pathways of our own brain. Now a study suggests that peripheral sensation and proprioception – the sense of where our limbs are in space – also play a role in this process, specifically when it comes to inferring other people’s expectations from the way they move.

Simone Bosbach (pictured) and colleagues tested two patients, IW and GL, who, because of sensory neuropathy, have the extremely rare condition of lacking any peripheral sensation or proprioception. The patients watched a video of a man lifting different boxes. When the man was always given correct information about the weight of the boxes, the patients, like controls, were able to correctly judge whether he’d lifted a heavy or light box. However, in a second experiment, when the man was occasionally given incorrect information about the boxes’ weight, the patients, unlike controls, were unable to judge from his movements whether or not a box weighed what he had expected (except when the task was made easier using larger boxes). Patient IW also couldn’t make this judgment correctly when he viewed videos of himself performing the same lifting task.

It’s not that the patients were incapable of forming a motor representation of the box lifting movements per se, otherwise IW wouldn’t have been able to lift the boxes. Rather, the authors believe the patients’ lack of peripheral sensation and proprioception affected their ability to activate or sustain a mental simulation of the lifting movements when watching them performed. The researchers said “[The patients’] reduced ability in the present task suggests that to judge mismatches between action preparation and performance in others, one has to access subconscious sensorimotor programmes, which IW and GL may lack”.

Bosbach, S., Cole, J., Prinz, W. & Knoblich, G. (2005). Inferring another’s expectation from action: the role of peripheral sensation. Nature Neuroscience, 8, 1295-1297.
You have read this article Social with the title October 2005. You can bookmark this page URL Thanks!

Coping with unwanted early retirement

People who are unable to find satisfactory work after being forced to retire early experience feelings of worthlessness and loss of self-esteem, just as younger unemployed people do, but they also experience unique pressures because of their age, including fearing that they will not be financially prepared for their final retirement, and a greater complexity of family responsibilities.

"this 'lost generation' of mature-aged unemployed people needs particular help..."

The findings come from a qualitative study by Rob Ranzijn and colleagues at the University of South Australia. They conducted group interviews with 27 participants aged between 45 and 71, all of whom were seeking work, or wished to change to more satisfactory work. Participants were invited to discuss their situation with the group.

The interviews were taped and transcribed and emerging themes were identified. Psychological themes included loss of self-worth, reduced quality of life, narrowed horizons (i.e. previous retirement plans were having to be reconsidered), inability to use talents and to contribute, effects on family relationships and concerns about the future. One participant said “Yes, it would be very frightening [not to get another job], it would be very, very frightening and I think that is something that you cannot afford at this time in our lives to be complacent about”.

Another issue that emerged was ‘skill atrophy’ – “the processes whereby continuing unemployment can lead to a progressive decay of skills and a perceived (by potential employers) decline in competencies”. This in turn led to what the researchers called the ‘peg-down phenomenon’ – “the older job-seekers’ reduced expectations of both the level of jobs attainable and the likelihood of attaining any such jobs”. In light of this, the authors recommended that “policies aiming to help mature-aged unemployed people re-enter the workforce must include focused training in the skills required in the current job market”.

The researchers concluded that this “’lost generation’ of mature-aged unemployed people needs particular help; otherwise they may live for another 30 or more years without ever again finding satisfactory employment”.

Ranzijn, R. Carson, E., Winefield, A.H. & Price D. (2005). On the scrap-heap at 45: The human impact of mature-aged unemployment. Journal of Occupational and Organisational Psychology. In Press, DOI: 10.1348/096317905X66828.
You have read this article Occupational with the title October 2005. You can bookmark this page URL Thanks!

...a pleasant thing it is for the eyes to behold the sun (Ecclesiastes 11.4)

It’s the excuse you’ve always needed to work outside on sunny days – researchers have shown that pleasantly warm, sunny weather can improve people’s mood and mental ability, but not if they’re stuck indoors. Matthew Keller and colleagues tested the mood, short-term memory and open-mindedness of 97 people on various Spring days in Michigan, USA. Nicer weather, indicated by higher temperature and barometric pressure, was associated with better mood, memory and a broader mindset, but only among participants who’d spent more than 30 minutes outside on the day they were tested. Among participants who’d spent less than 30 minutes outside, nicer weather was associated with poorer mood and cognitive ability. Perhaps, the authors suggested, “people consciously resent being cooped up indoors when the weather is pleasant in the Spring”.

"...Nicer weather was associated with better mood, memory and a broader mindset, but only among participants who’d spent more than 30 minutes outside".

In a second experiment conducted on various days in Spring and early Summer, 121 participants completed tests of their mood and short-term memory before and after relaxing for 30 minutes. Half the participants were asked to relax outdoors, the others indoors. Consistent with the first experiment, the researchers found that when the weather was good, participants’ mood and memory tended to have improved after they’d relaxed outdoors, but not if they’d relaxed indoors.

A final study was conducted to take into account other geographical locations and times of year. As before, more pleasant weather was found to enhance the mood of people who’d been outside for long enough, but it only had this benefit in Spring – probably because in Summer it can often get too hot for comfort, the authors said.

Keller, M.C., Fredrickson, B.L., Ybarra, O., Cote, S., Johnson, K., Mikels, J., Conway, A. & Wager, T. (2005). A warm heart and a clear head. The contingent effects of weather on mood and cognition. Psychological Science, 16, 724-731.
You have read this article Cognition with the title October 2005. You can bookmark this page URL Thanks!

Most genes that influence maths ability also affect reading

Diagnostic labels such as dyslexia and dyscalculia tend to highlight the separateness of various mental capabilities from general intelligence. But a new study has shown that most of the genes that influence young children’s mathematics ability also influence their reading and general intelligence. According to Robert Plomin and colleagues at the Social, Genetic and Developmental Psychiatry Centre at King’s College in London, this is probably because “a great variety of non-specific abilities, such as long-term memory, working memory and attention are involved in mathematical ability as well as in reading and general intelligence”. They made their finding by testing thousands of twins, some identical with matching genes, and others non-identical, who share half each other’s genes. The twins’ mathematics ability was assessed at seven years of age via teacher reports, and their reading and general intelligence was tested over the phone.

Plomin’s team found two thirds of the genetic influence on maths ability also explained variation in reading and general intelligence, thus suggesting most of the genes that affect maths also affect reading and general intelligence. Whereas genes tended to explain the similarity of a child’s performance across these domains, environmental factors tended to explain the differences. “One direction for future research is to identify the non-shared environmental factors that are experienced differently by twins, even identical twins, even in the same classroom and that contribute to differences in children’s relative performances in mathematics and reading”, the authors said.

Non-shared environmental factors are experiences that have uniquely affected one twin but not the other, even though they have been raised and taught together. Lead researcher Yulias Kovas told The Digest such factors could include “…pre-, peri- and post-natal influences, including childhood illnesses, differential parental influence, or differential effects of curricula on children”. Kovas added that “If these non-shared environmental factors can be identified, they could lead to more individualized curricula, although much more research is necessary to clarify whether such a move towards individualization in education is necessary or practically possible”.

Kovas, Y., Harlaar. N., Petrill, S.A. & Plomin, R. (2005). ‘Generalist genes’ and mathematics in 7-year-old twins. Intelligence, 33, 474-489.
You have read this article Cognition / Developmental / Intelligence with the title October 2005. You can bookmark this page URL Thanks!

You can't be blamed for the unknown unknowns

Research has shown that most of us suffer from a kind of ego-saving delusion that renders us hopelessly poor at recognising our own incompetencies. For example, people who are incompetent will tend to rate their own performance at a task only slightly lower than their more competent peers. Now Deanna Caputo and David Dunning have suggested there’s a simple explanation for this – we’re bad at judging our own ability they say, because, by definition, we’re ignorant of what we don’t know, or solutions we could have found.

They tested hundreds of students on various tasks, including a word game (Boggle), spotting an artist’s name embedded in his paintings (visual search), and spotting grammatical errors in a passage of text. After completing a task, participants were asked to evaluate their performance twice – first based on the solutions/ mistakes they knew they had identified, and then again after they’d been told about all the solutions/mistakes they’d missed. As the researchers predicted, they found the participants’ self-evaluations were far more accurate after they were given the extra information about the answers they had missed.

This phenomenon will be even more relevant when it comes to the less defined problems of real life, the researchers argued. “For example, it is impossible to catalogue all the solutions to such ill-defined tasks as designing an architecturally significant building, composing a classic country and western song, or writing the poem that resurrects the sonnet…”, the researchers said, “…as a consequence people are never really in a position to know just how well they have done because it is difficult to know all the alternative solutions they could have arrived at”.

Modestly, the researchers concluded by acknowledging that their investigation into this effect might well have been conducted better: “…there is [sic] bound to be some efforts we could have made but could not identify. We concede at this point that we do not know of them”.

Caputo, D. & Dunning, D. (2005). What you don’t know: The role played by errors of omission in imperfect self-assessments. Journal of Experimental Social Psychology, 41, 488-505.
You have read this article Cognition with the title October 2005. You can bookmark this page URL Thanks!

Depression linked with increased risk of epilepsy

People who have suffered from serious depression or who have attempted suicide could be at increased risk of developing epilepsy. That’s according to a team of American and Icelandic researchers who said more work was needed to explain the link, which they speculated could be related to levels of the neurotransmitters noradrenalin and serotonin.

"...patients presenting with a new onset unprovoked seizure should be evaluated for a history of suicide attempt and major depression".

Dale Hesdorffer (Columbia University) and colleagues recruited 324 Icelandic adult and child participants (median age 34 years) who had recently suffered two or more seizures that weren’t caused by fever, head trauma or central nervous system infection, thus pointing to a diagnosis of epilepsy. Six hundred and forty-seven age-matched control participants who lacked a history of epilepsy were selected using the Icelandic population registry. All the adult participants were interviewed over the phone to determine whether they had ever suffered from major depression or had attempted suicide. For both groups, only depression or suicide attempts that occurred prior to when the seizure patients had suffered their seizures were counted. The same information was obtained for the child participants by interviewing their parents.

Child and adult participants who had recently experienced unexplained seizures were 1.7 times more likely to have previously suffered from major depression than the control participants (i.e. 12 per cent of the seizure group vs. 7.4 per cent of the control group). And they were 5.1 times more likely to have attempted suicide in the past (i.e. 6.5 per cent of the seizure group vs. 1.4 per cent of the control group). Previous attempted suicide remained significantly more prevalent among the participants who’d recently suffered seizures, even after taking into account rates of prior depression and alcohol consumption.

“Clearly, patients presenting with a new onset unprovoked seizure should be evaluated for a history of suicide attempt and major depression”, the researchers advised.

Hesdorffer, D.C., Hauser, W.A., Olafsson, E., Ludvigsson, P. & Kjartansson, O. (2005). Depression and suicide attempt as risk factors for incident unprovoked seizures. In Press, Annals of Neurology. DOI: 10.1002/ana.20685.
You have read this article Mental health with the title October 2005. You can bookmark this page URL Thanks!

Mimicry the best form of flattery for computers too

After a social interaction, participants rate people who mimicked their movements or speech more favourably than they rate people who didn’t mimic them, even if they were unaware of the mimicry – a phenomenon that’s been dubbed the chameleon effect. Now Jeremy Bailenson and Nick Yee at Stanford University have shown this social effect of mimicry still occurs even when people are mimicked by what they know is a digital, computerised ‘agent’ seen in a virtual reality graphics environment, rather than by another human.

Sixty-nine male and female student participants wore a virtual reality helmet that displayed a 3-D image of the head and shoulders of a digital agent (see picture). For half the participants, the digital agent precisely mimicked their head movements with a four-second delay. For the other control participants, the digital agent did not mimic their movements, but instead moved its head as the previous participant had done. Eight participants detected they were being mimicked and were omitted from the analysis.

The digital agent spoke for 195 seconds about a proposed university campus security policy. After the experiment, all the participants answered questions about what the agent had said and what they thought of the agent. The digital agent was rated as more persuasive and likeable by participants whose head movements it had mimicked than by participants it didn’t mimic, thus suggesting the chameleon effect works for computers too.

As electronic communications become more sophisticated the researchers said their finding suggested digital mimicry could be used to manipulate and persuade. “Whether in immersive virtual reality, on-line chat rooms, or video games, algorithmic mimics may become commonplace, with agents mimicking users as frequently as their designers want, or as subtly or as obviously as they are programmed to do”, they said.

Bailenson, J.N. & Yee, N. (2005). Digital chameleons. Automatic assimilation of nonverbal gestures in immersive virtual reality environments. Psychological Science, 16, 814-819.
You have read this article Social with the title October 2005. You can bookmark this page URL Thanks!

Attention training for young children has noticeable benefit

Just five days of computer-based training over a few weeks can boost the attentional abilities of four-year-old children by an amount equivalent to half the increase in ability typically seen between the ages of four and six years of age. The finding raises the possibility of using such training as standard to prepare children before they start school, and of targeting the training at children with attentional problems.

M. Rosario Rueda at the University of Oregon and colleagues first tested the executive attentional ability of 49 four- and six-year-old children. This involved the children pressing a button to indicate which way a target fish was pointing while ignoring the direction of the surrounding fish.

Some of the children then received training that involved using a joystick to track a cartoon cat on a computer screen; using a joystick to place a cat where they thought a diving duck would emerge (anticipation exercise); picking out a target cartoon portrait from an array of distractors (stimulus discrimination); as well as a range of Stroop-like exercises, including indicating which of two lists of numbers contained more digits (e.g. 3333 vs. 666) while ignoring the actual size of repeated digit (e.g. 3 vs. 6). See here for more information.

When the children’s attentional ability was tested again, those who completed the training had improved more than controls, and their performance on IQ tests had also improved. Children who showed the poorest performance at the initial attention test benefited the most from the training. Moreover, electroencephalographic recordings of the children’s brains during the pre- and post-training attentional tests revealed some children showed pre-frontal activity after the training that they hadn’t shown before it: an indication they’d developed adult-like inhibitory activity that they lacked previously.

Rueda, M.R., Rothbart, M.K., McCandliss, B.D., Saccomanno, L. & Posner, M.I. (2005). Training, maturation, and genetic influences on the development of executive attention. Proceedings of the National Academy of Sciences, USA. In Press. DOI: 10.1073/pnas.0506897102.
You have read this article Cognition / Developmental with the title October 2005. You can bookmark this page URL Thanks!